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authorLinus Torvalds <torvalds@linux-foundation.org>2015-07-01 10:49:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-07-01 10:49:25 -0700
commit02201e3f1b46aed7c6348f406b7b40de80ba6de3 (patch)
tree2392c9098359725c195dd82a72b20ccedc1a1509
parent0890a264794f33df540fbaf274699146903b4e6b (diff)
parent20bdc2cfdbc484777b30b96fcdbb8994038f3ce1 (diff)
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell: "Main excitement here is Peter Zijlstra's lockless rbtree optimization to speed module address lookup. He found some abusers of the module lock doing that too. A little bit of parameter work here too; including Dan Streetman's breaking up the big param mutex so writing a parameter can load another module (yeah, really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were appended too" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits) modules: only use mod->param_lock if CONFIG_MODULES param: fix module param locks when !CONFIG_SYSFS. rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() module: add per-module param_lock module: make perm const params: suppress unused variable error, warn once just in case code changes. modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'. kernel/module.c: avoid ifdefs for sig_enforce declaration kernel/workqueue.c: remove ifdefs over wq_power_efficient kernel/params.c: export param_ops_bool_enable_only kernel/params.c: generalize bool_enable_only kernel/module.c: use generic module param operaters for sig_enforce kernel/params: constify struct kernel_param_ops uses sysfs: tightened sysfs permission checks module: Rework module_addr_{min,max} module: Use __module_address() for module_address_lookup() module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING module: Optimize __module_address() using a latched RB-tree rbtree: Implement generic latch_tree seqlock: Introduce raw_read_seqcount_latch() ...
-rw-r--r--arch/s390/kernel/perf_cpum_sf.c2
-rw-r--r--arch/um/drivers/hostaudio_kern.c20
-rw-r--r--arch/x86/kvm/mmu_audit.c2
-rw-r--r--arch/x86/platform/uv/uv_nmi.c2
-rw-r--r--drivers/block/null_blk.c4
-rw-r--r--drivers/char/ipmi/ipmi_watchdog.c6
-rw-r--r--drivers/dma/dmatest.c4
-rw-r--r--drivers/ide/ide.c2
-rw-r--r--drivers/infiniband/ulp/srp/ib_srp.c4
-rw-r--r--drivers/input/misc/ati_remote2.c4
-rw-r--r--drivers/input/mouse/psmouse-base.c2
-rw-r--r--drivers/misc/lis3lv02d/lis3lv02d.c2
-rw-r--r--drivers/mtd/ubi/block.c2
-rw-r--r--drivers/net/ethernet/myricom/myri10ge/myri10ge.c6
-rw-r--r--drivers/net/wireless/ath/wil6210/main.c4
-rw-r--r--drivers/net/wireless/libertas_tf/if_usb.c6
-rw-r--r--drivers/power/test_power.c16
-rw-r--r--drivers/thermal/intel_powerclamp.c4
-rw-r--r--drivers/tty/hvc/hvc_iucv.c2
-rw-r--r--drivers/tty/sysrq.c2
-rw-r--r--drivers/usb/atm/ueagle-atm.c4
-rw-r--r--drivers/video/fbdev/uvesafb.c2
-rw-r--r--drivers/video/fbdev/vt8623fb.c4
-rw-r--r--drivers/virtio/virtio_mmio.c2
-rw-r--r--fs/nfs/super.c2
-rw-r--r--include/linux/compiler.h15
-rw-r--r--include/linux/kernel.h18
-rw-r--r--include/linux/module.h46
-rw-r--r--include/linux/moduleparam.h99
-rw-r--r--include/linux/rbtree.h16
-rw-r--r--include/linux/rbtree_augmented.h21
-rw-r--r--include/linux/rbtree_latch.h212
-rw-r--r--include/linux/rcupdate.h15
-rw-r--r--include/linux/seqlock.h81
-rw-r--r--init/Kconfig29
-rw-r--r--kernel/jump_label.c10
-rw-r--r--kernel/module.c309
-rw-r--r--kernel/params.c116
-rw-r--r--kernel/time/timekeeping.c29
-rw-r--r--kernel/workqueue.c7
-rw-r--r--lib/bug.c7
-rw-r--r--lib/rbtree.c76
-rw-r--r--net/mac80211/rate.c4
-rw-r--r--net/sunrpc/auth.c2
-rw-r--r--net/sunrpc/xprtsock.c6
-rw-r--r--security/apparmor/lsm.c6
-rw-r--r--security/integrity/ima/ima_crypto.c2
-rw-r--r--sound/pci/hda/hda_intel.c2
48 files changed, 883 insertions, 355 deletions
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index e6a1578fc000..afe05bfb7e00 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1572,7 +1572,7 @@ static int param_set_sfb_size(const char *val, const struct kernel_param *kp)
}
#define param_check_sfb_size(name, p) __param_check(name, p, void)
-static struct kernel_param_ops param_ops_sfb_size = {
+static const struct kernel_param_ops param_ops_sfb_size = {
.set = param_set_sfb_size,
.get = param_get_sfb_size,
};
diff --git a/arch/um/drivers/hostaudio_kern.c b/arch/um/drivers/hostaudio_kern.c
index 9b90fdc4b151..f6b911cc3923 100644
--- a/arch/um/drivers/hostaudio_kern.c
+++ b/arch/um/drivers/hostaudio_kern.c
@@ -185,9 +185,9 @@ static int hostaudio_open(struct inode *inode, struct file *file)
int ret;
#ifdef DEBUG
- kparam_block_sysfs_write(dsp);
+ kernel_param_lock(THIS_MODULE);
printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp);
- kparam_unblock_sysfs_write(dsp);
+ kernel_param_unlock(THIS_MODULE);
#endif
state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
@@ -199,11 +199,11 @@ static int hostaudio_open(struct inode *inode, struct file *file)
if (file->f_mode & FMODE_WRITE)
w = 1;
- kparam_block_sysfs_write(dsp);
+ kernel_param_lock(THIS_MODULE);
mutex_lock(&hostaudio_mutex);
ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
mutex_unlock(&hostaudio_mutex);
- kparam_unblock_sysfs_write(dsp);
+ kernel_param_unlock(THIS_MODULE);
if (ret < 0) {
kfree(state);
@@ -260,17 +260,17 @@ static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
if (file->f_mode & FMODE_WRITE)
w = 1;
- kparam_block_sysfs_write(mixer);
+ kernel_param_lock(THIS_MODULE);
mutex_lock(&hostaudio_mutex);
ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0);
mutex_unlock(&hostaudio_mutex);
- kparam_unblock_sysfs_write(mixer);
+ kernel_param_unlock(THIS_MODULE);
if (ret < 0) {
- kparam_block_sysfs_write(dsp);
+ kernel_param_lock(THIS_MODULE);
printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', "
"err = %d\n", dsp, -ret);
- kparam_unblock_sysfs_write(dsp);
+ kernel_param_unlock(THIS_MODULE);
kfree(state);
return ret;
}
@@ -326,10 +326,10 @@ MODULE_LICENSE("GPL");
static int __init hostaudio_init_module(void)
{
- __kernel_param_lock();
+ kernel_param_lock(THIS_MODULE);
printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
dsp, mixer);
- __kernel_param_unlock();
+ kernel_param_unlock(THIS_MODULE);
module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
if (module_data.dev_audio < 0) {
diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c
index a4f62e6f2db2..03d518e499a6 100644
--- a/arch/x86/kvm/mmu_audit.c
+++ b/arch/x86/kvm/mmu_audit.c
@@ -297,7 +297,7 @@ static int mmu_audit_set(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops audit_param_ops = {
+static const struct kernel_param_ops audit_param_ops = {
.set = mmu_audit_set,
.get = param_get_bool,
};
diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c
index 7488cafab955..020c101c255f 100644
--- a/arch/x86/platform/uv/uv_nmi.c
+++ b/arch/x86/platform/uv/uv_nmi.c
@@ -104,7 +104,7 @@ static int param_set_local64(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops param_ops_local64 = {
+static const struct kernel_param_ops param_ops_local64 = {
.get = param_get_local64,
.set = param_set_local64,
};
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 6f9b7534928e..69de41a87b74 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -99,7 +99,7 @@ static int null_set_queue_mode(const char *str, const struct kernel_param *kp)
return null_param_store_val(str, &queue_mode, NULL_Q_BIO, NULL_Q_MQ);
}
-static struct kernel_param_ops null_queue_mode_param_ops = {
+static const struct kernel_param_ops null_queue_mode_param_ops = {
.set = null_set_queue_mode,
.get = param_get_int,
};
@@ -127,7 +127,7 @@ static int null_set_irqmode(const char *str, const struct kernel_param *kp)
NULL_IRQ_TIMER);
}
-static struct kernel_param_ops null_irqmode_param_ops = {
+static const struct kernel_param_ops null_irqmode_param_ops = {
.set = null_set_irqmode,
.get = param_get_int,
};
diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index 37b8be7cba95..0ac3bd1a5497 100644
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -208,7 +208,7 @@ static int set_param_timeout(const char *val, const struct kernel_param *kp)
return rv;
}
-static struct kernel_param_ops param_ops_timeout = {
+static const struct kernel_param_ops param_ops_timeout = {
.set = set_param_timeout,
.get = param_get_int,
};
@@ -270,14 +270,14 @@ static int set_param_wdog_ifnum(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops param_ops_wdog_ifnum = {
+static const struct kernel_param_ops param_ops_wdog_ifnum = {
.set = set_param_wdog_ifnum,
.get = param_get_int,
};
#define param_check_wdog_ifnum param_check_int
-static struct kernel_param_ops param_ops_str = {
+static const struct kernel_param_ops param_ops_str = {
.set = set_param_str,
.get = get_param_str,
};
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
index 220ee49633e4..b8576fd6bd0e 100644
--- a/drivers/dma/dmatest.c
+++ b/drivers/dma/dmatest.c
@@ -120,7 +120,7 @@ static struct dmatest_info {
static int dmatest_run_set(const char *val, const struct kernel_param *kp);
static int dmatest_run_get(char *val, const struct kernel_param *kp);
-static struct kernel_param_ops run_ops = {
+static const struct kernel_param_ops run_ops = {
.set = dmatest_run_set,
.get = dmatest_run_get,
};
@@ -195,7 +195,7 @@ static int dmatest_wait_get(char *val, const struct kernel_param *kp)
return param_get_bool(val, kp);
}
-static struct kernel_param_ops wait_ops = {
+static const struct kernel_param_ops wait_ops = {
.get = dmatest_wait_get,
.set = param_set_bool,
};
diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c
index e29b02ca9e91..f086ef387475 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -199,7 +199,7 @@ static int ide_set_dev_param_mask(const char *s, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops param_ops_ide_dev_mask = {
+static const struct kernel_param_ops param_ops_ide_dev_mask = {
.set = ide_set_dev_param_mask
};
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index eada8f758ad4..267dc4f75502 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -99,7 +99,7 @@ module_param(register_always, bool, 0444);
MODULE_PARM_DESC(register_always,
"Use memory registration even for contiguous memory regions");
-static struct kernel_param_ops srp_tmo_ops;
+static const struct kernel_param_ops srp_tmo_ops;
static int srp_reconnect_delay = 10;
module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
@@ -184,7 +184,7 @@ out:
return res;
}
-static struct kernel_param_ops srp_tmo_ops = {
+static const struct kernel_param_ops srp_tmo_ops = {
.get = srp_tmo_get,
.set = srp_tmo_set,
};
diff --git a/drivers/input/misc/ati_remote2.c b/drivers/input/misc/ati_remote2.c
index f63341f20b91..cfd58e87da26 100644
--- a/drivers/input/misc/ati_remote2.c
+++ b/drivers/input/misc/ati_remote2.c
@@ -94,7 +94,7 @@ static int ati_remote2_get_mode_mask(char *buffer,
static unsigned int channel_mask = ATI_REMOTE2_MAX_CHANNEL_MASK;
#define param_check_channel_mask(name, p) __param_check(name, p, unsigned int)
-static struct kernel_param_ops param_ops_channel_mask = {
+static const struct kernel_param_ops param_ops_channel_mask = {
.set = ati_remote2_set_channel_mask,
.get = ati_remote2_get_channel_mask,
};
@@ -103,7 +103,7 @@ MODULE_PARM_DESC(channel_mask, "Bitmask of channels to accept <15:Channel16>...<
static unsigned int mode_mask = ATI_REMOTE2_MAX_MODE_MASK;
#define param_check_mode_mask(name, p) __param_check(name, p, unsigned int)
-static struct kernel_param_ops param_ops_mode_mask = {
+static const struct kernel_param_ops param_ops_mode_mask = {
.set = ati_remote2_set_mode_mask,
.get = ati_remote2_get_mode_mask,
};
diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 7c4ba43d253e..ec3477036150 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -47,7 +47,7 @@ MODULE_LICENSE("GPL");
static unsigned int psmouse_max_proto = PSMOUSE_AUTO;
static int psmouse_set_maxproto(const char *val, const struct kernel_param *);
static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp);
-static struct kernel_param_ops param_ops_proto_abbrev = {
+static const struct kernel_param_ops param_ops_proto_abbrev = {
.set = psmouse_set_maxproto,
.get = psmouse_get_maxproto,
};
diff --git a/drivers/misc/lis3lv02d/lis3lv02d.c b/drivers/misc/lis3lv02d/lis3lv02d.c
index 4739689d23ad..fb8705fc3aca 100644
--- a/drivers/misc/lis3lv02d/lis3lv02d.c
+++ b/drivers/misc/lis3lv02d/lis3lv02d.c
@@ -115,7 +115,7 @@ static int param_set_axis(const char *val, const struct kernel_param *kp)
return ret;
}
-static struct kernel_param_ops param_ops_axis = {
+static const struct kernel_param_ops param_ops_axis = {
.set = param_set_axis,
.get = param_get_int,
};
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index 1a92d30689e7..ebf46ad2d513 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -162,7 +162,7 @@ static int __init ubiblock_set_param(const char *val,
return 0;
}
-static struct kernel_param_ops ubiblock_param_ops = {
+static const struct kernel_param_ops ubiblock_param_ops = {
.set = ubiblock_set_param,
};
module_param_cb(block, &ubiblock_param_ops, NULL, 0);
diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
index 2bae50292dcd..83651ac8ddb9 100644
--- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
+++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c
@@ -279,7 +279,7 @@ MODULE_FIRMWARE("myri10ge_eth_z8e.dat");
MODULE_FIRMWARE("myri10ge_rss_ethp_z8e.dat");
MODULE_FIRMWARE("myri10ge_rss_eth_z8e.dat");
-/* Careful: must be accessed under kparam_block_sysfs_write */
+/* Careful: must be accessed under kernel_param_lock() */
static char *myri10ge_fw_name = NULL;
module_param(myri10ge_fw_name, charp, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(myri10ge_fw_name, "Firmware image name");
@@ -3427,7 +3427,7 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp)
}
}
- kparam_block_sysfs_write(myri10ge_fw_name);
+ kernel_param_lock(THIS_MODULE);
if (myri10ge_fw_name != NULL) {
char *fw_name = kstrdup(myri10ge_fw_name, GFP_KERNEL);
if (fw_name) {
@@ -3435,7 +3435,7 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp)
set_fw_name(mgp, fw_name, true);
}
}
- kparam_unblock_sysfs_write(myri10ge_fw_name);
+ kernel_param_unlock(THIS_MODULE);
if (mgp->board_number < MYRI10GE_MAX_BOARDS &&
myri10ge_fw_names[mgp->board_number] != NULL &&
diff --git a/drivers/net/wireless/ath/wil6210/main.c b/drivers/net/wireless/ath/wil6210/main.c
index b9febab89167..6ca6193ab8a6 100644
--- a/drivers/net/wireless/ath/wil6210/main.c
+++ b/drivers/net/wireless/ath/wil6210/main.c
@@ -62,7 +62,7 @@ static int mtu_max_set(const char *val, const struct kernel_param *kp)
return ret;
}
-static struct kernel_param_ops mtu_max_ops = {
+static const struct kernel_param_ops mtu_max_ops = {
.set = mtu_max_set,
.get = param_get_uint,
};
@@ -91,7 +91,7 @@ static int ring_order_set(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops ring_order_ops = {
+static const struct kernel_param_ops ring_order_ops = {
.set = ring_order_set,
.get = param_get_uint,
};
diff --git a/drivers/net/wireless/libertas_tf/if_usb.c b/drivers/net/wireless/libertas_tf/if_usb.c
index 1a20cee5febe..799a2efe5793 100644
--- a/drivers/net/wireless/libertas_tf/if_usb.c
+++ b/drivers/net/wireless/libertas_tf/if_usb.c
@@ -821,15 +821,15 @@ static int if_usb_prog_firmware(struct if_usb_card *cardp)
lbtf_deb_enter(LBTF_DEB_USB);
- kparam_block_sysfs_write(fw_name);
+ kernel_param_lock(THIS_MODULE);
ret = request_firmware(&cardp->fw, lbtf_fw_name, &cardp->udev->dev);
if (ret < 0) {
pr_err("request_firmware() failed with %#x\n", ret);
pr_err("firmware %s not found\n", lbtf_fw_name);
- kparam_unblock_sysfs_write(fw_name);
+ kernel_param_unlock(THIS_MODULE);
goto done;
}
- kparam_unblock_sysfs_write(fw_name);
+ kernel_param_unlock(THIS_MODULE);
if (check_fwfile_format(cardp->fw->data, cardp->fw->size))
goto release_fw;
diff --git a/drivers/power/test_power.c b/drivers/power/test_power.c
index f986e0cca7ac..83c42ea88f2b 100644
--- a/drivers/power/test_power.c
+++ b/drivers/power/test_power.c
@@ -448,42 +448,42 @@ static int param_set_battery_voltage(const char *key,
#define param_get_battery_voltage param_get_int
-static struct kernel_param_ops param_ops_ac_online = {
+static const struct kernel_param_ops param_ops_ac_online = {
.set = param_set_ac_online,
.get = param_get_ac_online,
};
-static struct kernel_param_ops param_ops_usb_online = {
+static const struct kernel_param_ops param_ops_usb_online = {
.set = param_set_usb_online,
.get = param_get_usb_online,
};
-static struct kernel_param_ops param_ops_battery_status = {
+static const struct kernel_param_ops param_ops_battery_status = {
.set = param_set_battery_status,
.get = param_get_battery_status,
};
-static struct kernel_param_ops param_ops_battery_present = {
+static const struct kernel_param_ops param_ops_battery_present = {
.set = param_set_battery_present,
.get = param_get_battery_present,
};
-static struct kernel_param_ops param_ops_battery_technology = {
+static const struct kernel_param_ops param_ops_battery_technology = {
.set = param_set_battery_technology,
.get = param_get_battery_technology,
};
-static struct kernel_param_ops param_ops_battery_health = {
+static const struct kernel_param_ops param_ops_battery_health = {
.set = param_set_battery_health,
.get = param_get_battery_health,
};
-static struct kernel_param_ops param_ops_battery_capacity = {
+static const struct kernel_param_ops param_ops_battery_capacity = {
.set = param_set_battery_capacity,
.get = param_get_battery_capacity,
};
-static struct kernel_param_ops param_ops_battery_voltage = {
+static const struct kernel_param_ops param_ops_battery_voltage = {
.set = param_set_battery_voltage,
.get = param_get_battery_voltage,
};
diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index 2e6716104d3f..5820e8513927 100644
--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -119,7 +119,7 @@ exit:
return ret;
}
-static struct kernel_param_ops duration_ops = {
+static const struct kernel_param_ops duration_ops = {
.set = duration_set,
.get = param_get_int,
};
@@ -167,7 +167,7 @@ exit_win:
return ret;
}
-static struct kernel_param_ops window_size_ops = {
+static const struct kernel_param_ops window_size_ops = {
.set = window_size_set,
.get = param_get_int,
};
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c
index f78a87b07872..bb809cf36617 100644
--- a/drivers/tty/hvc/hvc_iucv.c
+++ b/drivers/tty/hvc/hvc_iucv.c
@@ -1345,7 +1345,7 @@ static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp)
#define param_check_vmidfilter(name, p) __param_check(name, p, void)
-static struct kernel_param_ops param_ops_vmidfilter = {
+static const struct kernel_param_ops param_ops_vmidfilter = {
.set = param_set_vmidfilter,
.get = param_get_vmidfilter,
};
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 2847108cc8dd..b5b427888b24 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -988,7 +988,7 @@ static int sysrq_reset_seq_param_set(const char *buffer,
return 0;
}
-static struct kernel_param_ops param_ops_sysrq_reset_seq = {
+static const struct kernel_param_ops param_ops_sysrq_reset_seq = {
.get = param_get_ushort,
.set = sysrq_reset_seq_param_set,
};
diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c
index 888998a7fe31..a2ae88dbda78 100644
--- a/drivers/usb/atm/ueagle-atm.c
+++ b/drivers/usb/atm/ueagle-atm.c
@@ -1599,7 +1599,7 @@ static void cmvs_file_name(struct uea_softc *sc, char *const cmv_name, int ver)
char file_arr[] = "CMVxy.bin";
char *file;
- kparam_block_sysfs_write(cmv_file);
+ kernel_param_lock(THIS_MODULE);
/* set proper name corresponding modem version and line type */
if (cmv_file[sc->modem_index] == NULL) {
if (UEA_CHIP_VERSION(sc) == ADI930)
@@ -1618,7 +1618,7 @@ static void cmvs_file_name(struct uea_softc *sc, char *const cmv_name, int ver)
strlcat(cmv_name, file, UEA_FW_NAME_MAX);
if (ver == 2)
strlcat(cmv_name, ".v2", UEA_FW_NAME_MAX);
- kparam_unblock_sysfs_write(cmv_file);
+ kernel_param_unlock(THIS_MODULE);
}
static int request_cmvs_old(struct uea_softc *sc,
diff --git a/drivers/video/fbdev/uvesafb.c b/drivers/video/fbdev/uvesafb.c
index d32d1c4d1b99..178ae93b7ebd 100644
--- a/drivers/video/fbdev/uvesafb.c
+++ b/drivers/video/fbdev/uvesafb.c
@@ -1977,7 +1977,7 @@ static int param_set_scroll(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops param_ops_scroll = {
+static const struct kernel_param_ops param_ops_scroll = {
.set = param_set_scroll,
};
#define param_check_scroll(name, p) __param_check(name, p, void)
diff --git a/drivers/video/fbdev/vt8623fb.c b/drivers/video/fbdev/vt8623fb.c
index ea7f056ed5fe..8bac309c24b9 100644
--- a/drivers/video/fbdev/vt8623fb.c
+++ b/drivers/video/fbdev/vt8623fb.c
@@ -754,9 +754,9 @@ static int vt8623_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
/* Prepare startup mode */
- kparam_block_sysfs_write(mode_option);
+ kernel_param_lock(THIS_MODULE);
rc = fb_find_mode(&(info->var), info, mode_option, NULL, 0, NULL, 8);
- kparam_unblock_sysfs_write(mode_option);
+ kernel_param_unlock(THIS_MODULE);
if (! ((rc == 1) || (rc == 2))) {
rc = -EINVAL;
dev_err(info->device, "mode %s not found\n", mode_option);
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 7a5e60dea6c5..10189b5b627f 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -691,7 +691,7 @@ static int vm_cmdline_get(char *buffer, const struct kernel_param *kp)
return strlen(buffer) + 1;
}
-static struct kernel_param_ops vm_cmdline_param_ops = {
+static const struct kernel_param_ops vm_cmdline_param_ops = {
.set = vm_cmdline_set,
.get = vm_cmdline_get,
};
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index f175b833b6ba..aa62004f1706 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2847,7 +2847,7 @@ static int param_set_portnr(const char *val, const struct kernel_param *kp)
*((unsigned int *)kp->arg) = num;
return 0;
}
-static struct kernel_param_ops param_ops_portnr = {
+static const struct kernel_param_ops param_ops_portnr = {
.set = param_set_portnr,
.get = param_get_uint,
};
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 26fc8bc77f85..7f8ad9593da7 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -475,6 +475,21 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
(volatile typeof(x) *)&(x); })
#define ACCESS_ONCE(x) (*__ACCESS_ONCE(x))
+/**
+ * lockless_dereference() - safely load a pointer for later dereference
+ * @p: The pointer to load
+ *
+ * Similar to rcu_dereference(), but for situations where the pointed-to
+ * object's lifetime is managed by something other than RCU. That
+ * "something other" might be reference counting or simple immortality.
+ */
+#define lockless_dereference(p) \
+({ \
+ typeof(p) _________p1 = READ_ONCE(p); \
+ smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+ (_________p1); \
+})
+
/* Ignore/forbid kprobes attach on very low level functions marked by this attribute: */
#ifdef CONFIG_KPROBES
# define __kprobes __attribute__((__section__(".kprobes.text")))
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 5acf5b70866d..cfa9351c7536 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -813,13 +813,15 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
#endif
/* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */
-#define VERIFY_OCTAL_PERMISSIONS(perms) \
- (BUILD_BUG_ON_ZERO((perms) < 0) + \
- BUILD_BUG_ON_ZERO((perms) > 0777) + \
- /* User perms >= group perms >= other perms */ \
- BUILD_BUG_ON_ZERO(((perms) >> 6) < (((perms) >> 3) & 7)) + \
- BUILD_BUG_ON_ZERO((((perms) >> 3) & 7) < ((perms) & 7)) + \
- /* Other writable? Generally considered a bad idea. */ \
- BUILD_BUG_ON_ZERO((perms) & 2) + \
+#define VERIFY_OCTAL_PERMISSIONS(perms) \
+ (BUILD_BUG_ON_ZERO((perms) < 0) + \
+ BUILD_BUG_ON_ZERO((perms) > 0777) + \
+ /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \
+ BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \
+ BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \
+ /* USER_WRITABLE >= GROUP_WRITABLE */ \
+ BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \
+ /* OTHER_WRITABLE? Generally considered a bad idea. */ \
+ BUILD_BUG_ON_ZERO((perms) & 2) + \
(perms))
#endif
diff --git a/include/linux/module.h b/include/linux/module.h
index 7ffe0851d244..d67b1932cc59 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -17,6 +17,7 @@
#include <linux/moduleparam.h>
#include <linux/jump_label.h>
#include <linux/export.h>
+#include <linux/rbtree_latch.h>
#include <linux/percpu.h>
#include <asm/module.h>
@@ -210,6 +211,13 @@ enum module_state {
MODULE_STATE_UNFORMED, /* Still setting it up. */
};
+struct module;
+
+struct mod_tree_node {
+ struct module *mod;
+ struct latch_tree_node node;
+};
+
struct module {
enum module_state state;
@@ -232,6 +240,9 @@ struct module {
unsigned int num_syms;
/* Kernel parameters. */
+#ifdef CONFIG_SYSFS
+ struct mutex param_lock;
+#endif
struct kernel_param *kp;
unsigned int num_kp;
@@ -271,8 +282,15 @@ struct module {
/* Startup function. */
int (*init)(void);
- /* If this is non-NULL, vfree after init() returns */
- void *module_init;
+ /*
+ * If this is non-NULL, vfree() after init() returns.
+ *
+ * Cacheline align here, such that:
+ * module_init, module_core, init_size, core_size,
+ * init_text_size, core_text_size and mtn_core::{mod,node[0]}
+ * are on the same cacheline.
+ */
+ void *module_init ____cacheline_aligned;
/* Here is the actual code + data, vfree'd on unload. */
void *module_core;
@@ -283,6 +301,16 @@ struct module {
/* The size of the executable code in each section. */
unsigned int init_text_size, core_text_size;
+#ifdef CONFIG_MODULES_TREE_LOOKUP
+ /*
+ * We want mtn_core::{mod,node[0]} to be in the same cacheline as the
+ * above entries such that a regular lookup will only touch one
+ * cacheline.
+ */
+ struct mod_tree_node mtn_core;
+ struct mod_tree_node mtn_init;
+#endif
+
/* Size of RO sections of the module (text+rodata) */
unsigned int init_ro_size, core_ro_size;
@@ -369,7 +397,7 @@ struct module {
ctor_fn_t *ctors;
unsigned int num_ctors;
#endif
-};
+} ____cacheline_aligned;
#ifndef MODULE_ARCH_INIT
#define MODULE_ARCH_INIT {}
#endif
@@ -423,14 +451,22 @@ struct symsearch {
bool unused;
};
-/* Search for an exported symbol by name. */
+/*
+ * Search for an exported symbol by name.
+ *
+ * Must be called with module_mutex held or preemption disabled.
+ */
const struct kernel_symbol *find_symbol(const char *name,
struct module **owner,
const unsigned long **crc,
bool gplok,
bool warn);
-/* Walk the exported symbol table */
+/*
+ * Walk the exported symbol table
+ *
+ * Must be called with module_mutex held or preemption disabled.
+ */
bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
struct module *owner,
void *data), void *data);
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index 6480dcaca275..c12f2147c350 100644
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -67,8 +67,9 @@ enum {
struct kernel_param {
const char *name;
+ struct module *mod;
const struct kernel_param_ops *ops;
- u16 perm;
+ const u16 perm;
s8 level;
u8 flags;
union {
@@ -108,7 +109,7 @@ struct kparam_array
*
* @perm is 0 if the the variable is not to appear in sysfs, or 0444
* for world-readable, 0644 for root-writable, etc. Note that if it
- * is writable, you may need to use kparam_block_sysfs_write() around
+ * is writable, you may need to use kernel_param_lock() around
* accesses (esp. charp, which can be kfreed when it changes).
*
* The @type is simply pasted to refer to a param_ops_##type and a
@@ -216,16 +217,16 @@ struct kparam_array
parameters. */
#define __module_param_call(prefix, name, ops, arg, perm, level, flags) \
/* Default value instead of permissions? */ \
- static const char __param_str_##name[] = prefix #name; \
+ static const char __param_str_##name[] = prefix #name; \
static struct kernel_param __moduleparam_const __param_##name \
__used \
__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
- = { __param_str_##name, ops, VERIFY_OCTAL_PERMISSIONS(perm), \
- level, flags, { arg } }
+ = { __param_str_##name, THIS_MODULE, ops, \
+ VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } }
/* Obsolete - use module_param_cb() */
#define module_param_call(name, set, get, arg, perm) \
- static struct kernel_param_ops __param_ops_##name = \
+ static const struct kernel_param_ops __param_ops_##name = \
{ .flags = 0, (void *)set, (void *)get }; \
__module_param_call(MODULE_PARAM_PREFIX, \
name, &__param_ops_##name, arg, \
@@ -238,58 +239,14 @@ __check_old_set_param(int (*oldset)(const char *, struct kernel_param *))
return 0;
}
-/**
- * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
- * @name: the name of the parameter
- *
- * There's no point blocking write on a paramter that isn't writable via sysfs!
- */
-#define kparam_block_sysfs_write(name) \
- do { \
- BUG_ON(!(__param_##name.perm & 0222)); \
- __kernel_param_lock(); \
- } while (0)
-
-/**
- * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
- * @name: the name of the parameter
- */
-#define kparam_unblock_sysfs_write(name) \
- do { \
- BUG_ON(!(__param_##name.perm & 0222)); \
- __kernel_param_unlock(); \
- } while (0)
-
-/**
- * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
- * @name: the name of the parameter
- *
- * This also blocks sysfs writes.
- */
-#define kparam_block_sysfs_read(name) \
- do { \
- BUG_ON(!(__param_##name.perm & 0444)); \
- __kernel_param_lock(); \
- } while (0)
-
-/**
- * kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
- * @name: the name of the parameter
- */
-#define kparam_unblock_sysfs_read(name) \
- do { \
- BUG_ON(!(__param_##name.perm & 0444)); \
- __kernel_param_unlock(); \
- } while (0)
-
#ifdef CONFIG_SYSFS
-extern void __kernel_param_lock(void);
-extern void __kernel_param_unlock(void);
+extern void kernel_param_lock(struct module *mod);
+extern void kernel_param_unlock(struct module *mod);
#else
-static inline void __kernel_param_lock(void)
+static inline void kernel_param_lock(struct module *mod)
{
}
-static inline void __kernel_param_unlock(void)
+static inline void kernel_param_unlock(struct module *mod)
{
}
#endif
@@ -386,64 +343,70 @@ static inline void destroy_params(const struct kernel_param *params,
#define __param_check(name, p, type) \
static inline type __always_unused *__check_##name(void) { return(p); }
-extern struct kernel_param_ops param_ops_byte;
+extern const struct kernel_param_ops param_ops_byte;
extern int param_set_byte(const char *val, const struct kernel_param *kp);
extern int param_get_byte(char *buffer, const struct kernel_param *kp);
#define param_check_byte(name, p) __param_check(name, p, unsigned char)
-extern struct kernel_param_ops param_ops_short;
+extern const struct kernel_param_ops param_ops_short;
extern int param_set_short(const char *val, const struct kernel_param *kp);
extern int param_get_short(char *buffer, const struct kernel_param *kp);
#define param_check_short(name, p) __param_check(name, p, short)
-extern struct kernel_param_ops param_ops_ushort;
+extern const struct kernel_param_ops param_ops_ushort;
extern int param_set_ushort(const char *val, const struct kernel_param *kp);
extern int param_get_ushort(char *buffer, const struct kernel_param *kp);
#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
-extern struct kernel_param_ops param_ops_int;
+extern const struct kernel_param_ops param_ops_int;
extern int param_set_int(const char *val, const struct kernel_param *kp);
extern int param_get_int(char *buffer, const struct kernel_param *kp);
#define param_check_int(name, p) __param_check(name, p, int)
-extern struct kernel_param_ops param_ops_uint;
+extern const struct kernel_param_ops param_ops_uint;
extern int param_set_uint(const char *val, const struct kernel_param *kp);
extern int param_get_uint(char *buffer, const struct kernel_param *kp);
#define param_check_uint(name, p) __param_check(name, p, unsigned int)
-extern struct kernel_param_ops param_ops_long;
+extern const struct kernel_param_ops param_ops_long;
extern int param_set_long(const char *val, const struct kernel_param *kp);
extern int param_get_long(char *buffer, const struct kernel_param *kp);
#define param_check_long(name, p) __param_check(name, p, long)
-extern struct kernel_param_ops param_ops_ulong;
+extern const struct kernel_param_ops param_ops_ulong;
extern int param_set_ulong(const char *val, const struct kernel_param *kp);
extern int param_get_ulong(char *buffer, const struct kernel_param *kp);
#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
-extern struct kernel_param_ops param_ops_ullong;
+extern const struct kernel_param_ops param_ops_ullong;
extern int param_set_ullong(const char *val, const struct kernel_param *kp);
extern int param_get_ullong(char *buffer, const struct kernel_param *kp);
#define param_check_ullong(name, p) __param_check(name, p, unsigned long long)
-extern struct kernel_param_ops param_ops_charp;
+extern const struct kernel_param_ops param_ops_charp;
extern int param_set_charp(const char *val, const struct kernel_param *kp);
extern int param_get_charp(char *buffer, const struct kernel_param *kp);
#define param_check_charp(name, p) __param_check(name, p, char *)
/* We used to allow int as well as bool. We're taking that away! */
-extern struct kernel_param_ops param_ops_bool;
+extern const struct kernel_param_ops param_ops_bool;
extern int param_set_bool(const char *val, const struct kernel_param *kp);
extern int param_get_bool(char *buffer, const struct kernel_param *kp);
#define param_check_bool(name, p) __param_check(name, p, bool)
-extern struct kernel_param_ops param_ops_invbool;
+extern const struct kernel_param_ops param_ops_bool_enable_only;
+extern int param_set_bool_enable_only(const char *val,
+ const struct kernel_param *kp);
+/* getter is the same as for the regular bool */
+#define param_check_bool_enable_only param_check_bool
+
+extern const struct kernel_param_ops param_ops_invbool;
extern int param_set_invbool(const char *val, const struct kernel_param *kp);
extern int param_get_invbool(char *buffer, const struct kernel_param *kp);
#define param_check_invbool(name, p) __param_check(name, p, bool)
/* An int, which can only be set like a bool (though it shows as an int). */
-extern struct kernel_param_ops param_ops_bint;
+extern const struct kernel_param_ops param_ops_bint;
extern int param_set_bint(const char *val, const struct kernel_param *kp);
#define param_get_bint param_get_int
#define param_check_bint param_check_int
@@ -487,9 +450,9 @@ extern int param_set_bint(const char *val, const struct kernel_param *kp);
perm, -1, 0); \
__MODULE_PARM_TYPE(name, "array of " #type)
-extern struct kernel_param_ops param_array_ops;
+extern const struct kernel_param_ops param_array_ops;
-extern struct kernel_param_ops param_ops_string;
+extern const struct kernel_param_ops param_ops_string;
extern int param_set_copystring(const char *val, const struct kernel_param *);
extern int param_get_string(char *buffer, const struct kernel_param *kp);
diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h
index fb31765e935a..830c4992088d 100644
--- a/include/linux/rbtree.h
+++ b/include/linux/rbtree.h
@@ -31,6 +31,7 @@
#include <linux/kernel.h>
#include <linux/stddef.h>
+#include <linux/rcupdate.h>
struct rb_node {
unsigned long __rb_parent_color;
@@ -73,11 +74,11 @@ extern struct rb_node *rb_first_postorder(const struct rb_root *);
extern struct rb_node *rb_next_postorder(const struct rb_node *);
/* Fast replacement of a single node without remove/rebalance/add/rebalance */
-extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
+extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root);
-static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
- struct rb_node ** rb_link)
+static inline void rb_link_node(struct rb_node *node, struct rb_node *parent,
+ struct rb_node **rb_link)
{
node->__rb_parent_color = (unsigned long)parent;
node->rb_left = node->rb_right = NULL;
@@ -85,6 +86,15 @@ static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
*rb_link = node;
}
+static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent,
+ struct rb_node **rb_link)
+{
+ node->__rb_parent_color = (unsigned long)parent;
+ node->rb_left = node->rb_right = NULL;
+
+ rcu_assign_pointer(*rb_link, node);
+}
+
#define rb_entry_safe(ptr, type, member) \
({ typeof(ptr) ____ptr = (ptr); \
____ptr ? rb_entry(____ptr, type, member) : NULL; \
diff --git a/include/linux/rbtree_augmented.h b/include/linux/rbtree_augmented.h
index 378c5ee75f78..14d7b831b63a 100644
--- a/include/linux/rbtree_augmented.h
+++ b/include/linux/rbtree_augmented.h
@@ -123,11 +123,11 @@ __rb_change_child(struct rb_node *old, struct rb_node *new,
{
if (parent) {
if (parent->rb_left == old)
- parent->rb_left = new;
+ WRITE_ONCE(parent->rb_left, new);
else
- parent->rb_right = new;
+ WRITE_ONCE(parent->rb_right, new);
} else
- root->rb_node = new;
+ WRITE_ONCE(root->rb_node, new);
}
extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
@@ -137,7 +137,8 @@ static __always_inline struct rb_node *
__rb_erase_augmented(struct rb_node *node, struct rb_root *root,
const struct rb_augment_callbacks *augment)
{
- struct rb_node *child = node->rb_right, *tmp = node->rb_left;
+ struct rb_node *child = node->rb_right;
+ struct rb_node *tmp = node->rb_left;
struct rb_node *parent, *rebalance;
unsigned long pc;
@@ -167,6 +168,7 @@ __rb_erase_augmented(struct rb_node *node, struct rb_root *root,
tmp = parent;
} else {
struct rb_node *successor = child, *child2;
+
tmp = child->rb_left;
if (!tmp) {
/*
@@ -180,6 +182,7 @@ __rb_erase_augmented(struct rb_node *node, struct rb_root *root,
*/
parent = successor;
child2 = successor->rb_right;
+
augment->copy(node, successor);
} else {
/*
@@ -201,19 +204,23 @@ __rb_erase_augmented(struct rb_node *node, struct rb_root *root,
successor = tmp;
tmp = tmp->rb_left;
} while (tmp);
- parent->rb_left = child2 = successor->rb_right;
- successor->rb_right = child;
+ child2 = successor->rb_right;
+ WRITE_ONCE(parent->rb_left, child2);
+ WRITE_ONCE(successor->rb_right, child);
rb_set_parent(child, successor);
+
augment->copy(node, successor);
augment->propagate(parent, successor);
}
- successor->rb_left = tmp = node->rb_left;
+ tmp = node->rb_left;
+ WRITE_ONCE(successor->rb_left, tmp);
rb_set_parent(tmp, successor);
pc = node->__rb_parent_color;
tmp = __rb_parent(pc);
__rb_change_child(node, successor, tmp, root);
+
if (child2) {
successor->__rb_parent_color = pc;
rb_set_parent_color(child2, parent, RB_BLACK);
diff --git a/include/linux/rbtree_latch.h b/include/linux/rbtree_latch.h
new file mode 100644
index 000000000000..4f3432c61d12
--- /dev/null
+++ b/include/linux/rbtree_latch.h
@@ -0,0 +1,212 @@
+/*
+ * Latched RB-trees
+ *
+ * Copyright (C) 2015 Intel Corp., Peter Zijlstra <peterz@infradead.org>
+ *
+ * Since RB-trees have non-atomic modifications they're not immediately suited
+ * for RCU/lockless queries. Even though we made RB-tree lookups non-fatal for
+ * lockless lookups; we cannot guarantee they return a correct result.
+ *
+ * The simplest solution is a seqlock + RB-tree, this will allow lockless
+ * lookups; but has the constraint (inherent to the seqlock) that read sides
+ * cannot nest in write sides.
+ *
+ * If we need to allow unconditional lookups (say as required for NMI context
+ * usage) we need a more complex setup; this data structure provides this by
+ * employing the latch technique -- see @raw_write_seqcount_latch -- to
+ * implement a latched RB-tree which does allow for unconditional lookups by
+ * virtue of always having (at least) one stable copy of the tree.
+ *
+ * However, while we have the guarantee that there is at all times one stable
+ * copy, this does not guarantee an iteration will not observe modifications.
+ * What might have been a stable copy at the start of the iteration, need not
+ * remain so for the duration of the iteration.
+ *
+ * Therefore, this does require a lockless RB-tree iteration to be non-fatal;
+ * see the comment in lib/rbtree.c. Note however that we only require the first
+ * condition -- not seeing partial stores -- because the latch thing isolates
+ * us from loops. If we were to interrupt a modification the lookup would be
+ * pointed at the stable tree and complete while the modification was halted.
+ */
+
+#ifndef RB_TREE_LATCH_H
+#define RB_TREE_LATCH_H
+
+#include <linux/rbtree.h>
+#include <linux/seqlock.h>
+
+struct latch_tree_node {
+ struct rb_node node[2];
+};
+
+struct latch_tree_root {
+ seqcount_t seq;
+ struct rb_root tree[2];
+};
+
+/**
+ * latch_tree_ops - operators to define the tree order
+ * @less: used for insertion; provides the (partial) order between two elements.
+ * @comp: used for lookups; provides the order between the search key and an element.
+ *
+ * The operators are related like:
+ *
+ * comp(a->key,b) < 0 := less(a,b)
+ * comp(a->key,b) > 0 := less(b,a)
+ * comp(a->key,b) == 0 := !less(a,b) && !less(b,a)
+ *
+ * If these operators define a partial order on the elements we make no
+ * guarantee on which of the elements matching the key is found. See
+ * latch_tree_find().
+ */
+struct latch_tree_ops {
+ bool (*less)(struct latch_tree_node *a, struct latch_tree_node *b);
+ int (*comp)(void *key, struct latch_tree_node *b);
+};
+
+static __always_inline struct latch_tree_node *
+__lt_from_rb(struct rb_node *node, int idx)
+{
+ return container_of(node, struct latch_tree_node, node[idx]);
+}
+
+static __always_inline void
+__lt_insert(struct latch_tree_node *ltn, struct latch_tree_root *ltr, int idx,
+ bool (*less)(struct latch_tree_node *a, struct latch_tree_node *b))
+{
+ struct rb_root *root = &ltr->tree[idx];
+ struct rb_node **link = &root->rb_node;
+ struct rb_node *node = &ltn->node[idx];
+ struct rb_node *parent = NULL;
+ struct latch_tree_node *ltp;
+
+ while (*link) {
+ parent = *link;
+ ltp = __lt_from_rb(parent, idx);
+
+ if (less(ltn, ltp))
+ link = &parent->rb_left;
+ else
+ link = &parent->rb_right;
+ }
+
+ rb_link_node_rcu(node, parent, link);
+ rb_insert_color(node, root);
+}
+
+static __always_inline void
+__lt_erase(struct latch_tree_node *ltn, struct latch_tree_root *ltr, int idx)
+{
+ rb_erase(&ltn->node[idx], &ltr->tree[idx]);
+}
+
+static __always_inline struct latch_tree_node *
+__lt_find(void *key, struct latch_tree_root *ltr, int idx,
+ int (*comp)(void *key, struct latch_tree_node *node))
+{
+ struct rb_node *node = rcu_dereference_raw(ltr->tree[idx].rb_node);
+ struct latch_tree_node *ltn;
+ int c;
+
+ while (node) {
+ ltn = __lt_from_rb(node, idx);
+ c = comp(key, ltn);
+
+ if (c < 0)
+ node = rcu_dereference_raw(node->rb_left);
+ else if (c > 0)
+ node = rcu_dereference_raw(node->rb_right);
+ else
+ return ltn;
+ }
+
+ return NULL;
+}
+
+/**
+ * latch_tree_insert() - insert @node into the trees @root
+ * @node: nodes to insert
+ * @root: trees to insert @node into
+ * @ops: operators defining the node order
+ *
+ * It inserts @node into @root in an ordered fashion such that we can always
+ * observe one complete tree. See the comment for raw_write_seqcount_latch().
+ *
+ * The inserts use rcu_assign_pointer() to publish the element such that the
+ * tree structure is stored before we can observe the new @node.
+ *
+ * All modifications (latch_tree_insert, latch_tree_remove) are assumed to be
+ * serialized.
+ */
+static __always_inline void
+latch_tree_insert(struct latch_tree_node *node,
+ struct latch_tree_root *root,
+ const struct latch_tree_ops *ops)
+{
+ raw_write_seqcount_latch(&root->seq);
+ __lt_insert(node, root, 0, ops->less);
+ raw_write_seqcount_latch(&root->seq);
+ __lt_insert(node, root, 1, ops->less);
+}
+
+/**
+ * latch_tree_erase() - removes @node from the trees @root
+ * @node: nodes to remote
+ * @root: trees to remove @node from
+ * @ops: operators defining the node order
+ *
+ * Removes @node from the trees @root in an ordered fashion such that we can
+ * always observe one complete tree. See the comment for
+ * raw_write_seqcount_latch().
+ *
+ * It is assumed that @node will observe one RCU quiescent state before being
+ * reused of freed.
+ *
+ * All modifications (latch_tree_insert, latch_tree_remove) are assumed to be
+ * serialized.
+ */
+static __always_inline void
+latch_tree_erase(struct latch_tree_node *node,
+ struct latch_tree_root *root,
+ const struct latch_tree_ops *ops)
+{
+ raw_write_seqcount_latch(&root->seq);
+ __lt_erase(node, root, 0);
+ raw_write_seqcount_latch(&root->seq);
+ __lt_erase(node, root, 1);
+}
+
+/**
+ * latch_tree_find() - find the node matching @key in the trees @root
+ * @key: search key
+ * @root: trees to search for @key
+ * @ops: operators defining the node order
+ *
+ * Does a lockless lookup in the trees @root for the node matching @key.
+ *
+ * It is assumed that this is called while holding the appropriate RCU read
+ * side lock.
+ *
+ * If the operators define a partial order on the elements (there are multiple
+ * elements which have the same key value) it is undefined which of these
+ * elements will be found. Nor is it possible to iterate the tree to find
+ * further elements with the same key value.
+ *
+ * Returns: a pointer to the node matching @key or NULL.
+ */
+static __always_inline struct latch_tree_node *
+latch_tree_find(void *key, struct latch_tree_root *root,
+ const struct latch_tree_ops *ops)
+{
+ struct latch_tree_node *node;
+ unsigned int seq;
+
+ do {
+ seq = raw_read_seqcount_latch(&root->seq);
+ node = __lt_find(key, root, seq & 1, ops->comp);
+ } while (read_seqcount_retry(&root->seq, seq));
+
+ return node;
+}
+
+#endif /* RB_TREE_LATCH_H */
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 33a056bb886f..4cf5f51b4c9c 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -633,21 +633,6 @@ static inline void rcu_preempt_sleep_check(void)
#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
/**
- * lockless_dereference() - safely load a pointer for later dereference
- * @p: The pointer to load
- *
- * Similar to rcu_dereference(), but for situations where the pointed-to
- * object's lifetime is managed by something other than RCU. That
- * "something other" might be reference counting or simple immortality.
- */
-#define lockless_dereference(p) \
-({ \
- typeof(p) _________p1 = READ_ONCE(p); \
- smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
- (_________p1); \
-})
-
-/**
* rcu_assign_pointer() - assign to RCU-protected pointer
* @p: pointer to assign to
* @v: value to assign (publish)
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 486e685a226a..e0582106ef4f 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -35,6 +35,7 @@
#include <linux/spinlock.h>
#include <linux/preempt.h>
#include <linux/lockdep.h>
+#include <linux/compiler.h>
#include <asm/processor.h>
/*
@@ -274,9 +275,87 @@ static inline void raw_write_seqcount_barrier(seqcount_t *s)
s->sequence++;
}
-/*
+static inline int raw_read_seqcount_latch(seqcount_t *s)
+{
+ return lockless_dereference(s->sequence);
+}
+
+/**
* raw_write_seqcount_latch - redirect readers to even/odd copy
* @s: pointer to seqcount_t
+ *
+ * The latch technique is a multiversion concurrency control method that allows
+ * queries during non-atomic modifications. If you can guarantee queries never
+ * interrupt the modification -- e.g. the concurrency is strictly between CPUs
+ * -- you most likely do not need this.
+ *
+ * Where the traditional RCU/lockless data structures rely on atomic
+ * modifications to ensure queries observe either the old or the new state the
+ * latch allows the same for non-atomic updates. The trade-off is doubling the
+ * cost of storage; we have to maintain two copies of the entire data
+ * structure.
+ *
+ * Very simply put: we first modify one copy and then the other. This ensures
+ * there is always one copy in a stable state, ready to give us an answer.
+ *
+ * The basic form is a data structure like:
+ *
+ * struct latch_struct {
+ * seqcount_t seq;
+ * struct data_struct data[2];
+ * };
+ *
+ * Where a modification, which is assumed to be externally serialized, does the
+ * following:
+ *
+ * void latch_modify(struct latch_struct *latch, ...)
+ * {
+ * smp_wmb(); <- Ensure that the last data[1] update is visible
+ * latch->seq++;
+ * smp_wmb(); <- Ensure that the seqcount update is visible
+ *
+ * modify(latch->data[0], ...);
+ *
+ * smp_wmb(); <- Ensure that the data[0] update is visible
+ * latch->seq++;
+ * smp_wmb(); <- Ensure that the seqcount update is visible
+ *
+ * modify(latch->data[1], ...);
+ * }
+ *
+ * The query will have a form like:
+ *
+ * struct entry *latch_query(struct latch_struct *latch, ...)
+ * {
+ * struct entry *entry;
+ * unsigned seq, idx;
+ *
+ * do {
+ * seq = lockless_dereference(latch->seq);
+ *
+ * idx = seq & 0x01;
+ * entry = data_query(latch->data[idx], ...);
+ *
+ * smp_rmb();
+ * } while (seq != latch->seq);
+ *
+ * return entry;
+ * }
+ *
+ * So during the modification, queries are first redirected to data[1]. Then we
+ * modify data[0]. When that is complete, we redirect queries back to data[0]
+ * and we can modify data[1].
+ *
+ * NOTE: The non-requirement for atomic modifications does _NOT_ include
+ * the publishing of new entries in the case where data is a dynamic
+ * data structure.
+ *
+ * An iteration might start in data[0] and get suspended long enough
+ * to miss an entire modification sequence, once it resumes it might
+ * observe the new entry.
+ *
+ * NOTE: When data is a dynamic data structure; one should use regular RCU
+ * patterns to manage the lifetimes of the objects within.
*/
static inline void raw_write_seqcount_latch(seqcount_t *s)
{
diff --git a/init/Kconfig b/init/Kconfig
index 7d1ffd2ae536..bcc41bd19999 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1941,26 +1941,21 @@ config MODULE_COMPRESS
bool "Compress modules on installation"
depends on MODULES
help
- This option compresses the kernel modules when 'make
- modules_install' is run.
- The modules will be compressed either using gzip or xz depend on the
- choice made in "Compression algorithm".
+ Compresses kernel modules when 'make modules_install' is run; gzip or
+ xz depending on "Compression algorithm" below.
- module-init-tools has support for gzip format while kmod handle gzip
- and xz compressed modules.
+ module-init-tools MAY support gzip, and kmod MAY support gzip and xz.
- When a kernel module is installed from outside of the main kernel
- source and uses the Kbuild system for installing modules then that
- kernel module will also be compressed when it is installed.
+ Out-of-tree kernel modules installed using Kbuild will also be
+ compressed upon installation.
- This option provides little benefit when the modules are to be used inside
- an initrd or initramfs, it generally is more efficient to compress the whole
- initrd or initramfs instead.
+ Note: for modules inside an initrd or initramfs, it's more efficient
+ to compress the whole initrd or initramfs instead.
- This is fully compatible with signed modules while the signed module is
- compressed. module-init-tools or kmod handles decompression and provide to
- other layer the uncompressed but signed payload.
+ Note: This is fully compatible with signed modules.
+
+ If in doubt, say N.
choice
prompt "Compression algorithm"
@@ -1982,6 +1977,10 @@ endchoice
endif # MODULES
+config MODULES_TREE_LOOKUP
+ def_bool y
+ depends on PERF_EVENTS || TRACING
+
config INIT_ALL_POSSIBLE
bool
help
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 9019f15deab2..52ebaca1b9fc 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -302,7 +302,7 @@ static int jump_label_add_module(struct module *mod)
continue;
key = iterk;
- if (__module_address(iter->key) == mod) {
+ if (within_module(iter->key, mod)) {
/*
* Set key->entries to iter, but preserve JUMP_LABEL_TRUE_BRANCH.
*/
@@ -339,7 +339,7 @@ static void jump_label_del_module(struct module *mod)
key = (struct static_key *)(unsigned long)iter->key;
- if (__module_address(iter->key) == mod)
+ if (within_module(iter->key, mod))
continue;
prev = &key->next;
@@ -443,14 +443,16 @@ static void jump_label_update(struct static_key *key, int enable)
{
struct jump_entry *stop = __stop___jump_table;
struct jump_entry *entry = jump_label_get_entries(key);
-
#ifdef CONFIG_MODULES
- struct module *mod = __module_address((unsigned long)key);
+ struct module *mod;
__jump_label_mod_update(key, enable);
+ preempt_disable();
+ mod = __module_address((unsigned long)key);
if (mod)
stop = mod->jump_entries + mod->num_jump_entries;
+ preempt_enable();
#endif
/* if there are no users, entry can be NULL */
if (entry)
diff --git a/kernel/module.c b/kernel/module.c
index f80a97f7da1f..3e0e19763d24 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -101,48 +101,201 @@
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
static LIST_HEAD(modules);
-#ifdef CONFIG_KGDB_KDB
-struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
-#endif /* CONFIG_KGDB_KDB */
-#ifdef CONFIG_MODULE_SIG
-#ifdef CONFIG_MODULE_SIG_FORCE
-static bool sig_enforce = true;
-#else
-static bool sig_enforce = false;
+#ifdef CONFIG_MODULES_TREE_LOOKUP
+
+/*
+ * Use a latched RB-tree for __module_address(); this allows us to use
+ * RCU-sched lookups of the address from any context.
+ *
+ * Because modules have two address ranges: init and core, we need two
+ * latch_tree_nodes entries. Therefore we need the back-pointer from
+ * mod_tree_node.
+ *
+ * Because init ranges are short lived we mark them unlikely and have placed
+ * them outside the critical cacheline in struct module.
+ *
+ * This is conditional on PERF_EVENTS || TRACING because those can really hit
+ * __module_address() hard by doing a lot of stack unwinding; potentially from
+ * NMI context.
+ */
-static int param_set_bool_enable_only(const char *val,
- const struct kernel_param *kp)
+static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
{
- int err;
- bool test;
- struct kernel_param dummy_kp = *kp;
+ struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
+ struct module *mod = mtn->mod;
- dummy_kp.arg = &test;
+ if (unlikely(mtn == &mod->mtn_init))
+ return (unsigned long)mod->module_init;
- err = param_set_bool(val, &dummy_kp);
- if (err)
- return err;
+ return (unsigned long)mod->module_core;
+}
+
+static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
+{
+ struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
+ struct module *mod = mtn->mod;
- /* Don't let them unset it once it's set! */
- if (!test && sig_enforce)
- return -EROFS;
+ if (unlikely(mtn == &mod->mtn_init))
+ return (unsigned long)mod->init_size;
+
+ return (unsigned long)mod->core_size;
+}
+
+static __always_inline bool
+mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
+{
+ return __mod_tree_val(a) < __mod_tree_val(b);
+}
+
+static __always_inline int
+mod_tree_comp(void *key, struct latch_tree_node *n)
+{
+ unsigned long val = (unsigned long)key;
+ unsigned long start, end;
+
+ start = __mod_tree_val(n);
+ if (val < start)
+ return -1;
+
+ end = start + __mod_tree_size(n);
+ if (val >= end)
+ return 1;
- if (test)
- sig_enforce = true;
return 0;
}
-static const struct kernel_param_ops param_ops_bool_enable_only = {
- .flags = KERNEL_PARAM_OPS_FL_NOARG,
- .set = param_set_bool_enable_only,
- .get = param_get_bool,
+static const struct latch_tree_ops mod_tree_ops = {
+ .less = mod_tree_less,
+ .comp = mod_tree_comp,
};
-#define param_check_bool_enable_only param_check_bool
+static struct mod_tree_root {
+ struct latch_tree_root root;
+ unsigned long addr_min;
+ unsigned long addr_max;
+} mod_tree __cacheline_aligned = {
+ .addr_min = -1UL,
+};
+
+#define module_addr_min mod_tree.addr_min
+#define module_addr_max mod_tree.addr_max
+
+static noinline void __mod_tree_insert(struct mod_tree_node *node)
+{
+ latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+static void __mod_tree_remove(struct mod_tree_node *node)
+{
+ latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+/*
+ * These modifications: insert, remove_init and remove; are serialized by the
+ * module_mutex.
+ */
+static void mod_tree_insert(struct module *mod)
+{
+ mod->mtn_core.mod = mod;
+ mod->mtn_init.mod = mod;
+
+ __mod_tree_insert(&mod->mtn_core);
+ if (mod->init_size)
+ __mod_tree_insert(&mod->mtn_init);
+}
+
+static void mod_tree_remove_init(struct module *mod)
+{
+ if (mod->init_size)
+ __mod_tree_remove(&mod->mtn_init);
+}
+
+static void mod_tree_remove(struct module *mod)
+{
+ __mod_tree_remove(&mod->mtn_core);
+ mod_tree_remove_init(mod);
+}
+
+static struct module *mod_find(unsigned long addr)
+{
+ struct latch_tree_node *ltn;
+
+ ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
+ if (!ltn)
+ return NULL;
+
+ return container_of(ltn, struct mod_tree_node, node)->mod;
+}
+
+#else /* MODULES_TREE_LOOKUP */
+
+static unsigned long module_addr_min = -1UL, module_addr_max = 0;
+
+static void mod_tree_insert(struct module *mod) { }
+static void mod_tree_remove_init(struct module *mod) { }
+static void mod_tree_remove(struct module *mod) { }
+
+static struct module *mod_find(unsigned long addr)
+{
+ struct module *mod;
+
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (within_module(addr, mod))
+ return mod;
+ }
+
+ return NULL;
+}
+
+#endif /* MODULES_TREE_LOOKUP */
+
+/*
+ * Bounds of module text, for speeding up __module_address.
+ * Protected by module_mutex.
+ */
+static void __mod_update_bounds(void *base, unsigned int size)
+{
+ unsigned long min = (unsigned long)base;
+ unsigned long max = min + size;
+
+ if (min < module_addr_min)
+ module_addr_min = min;
+ if (max > module_addr_max)
+ module_addr_max = max;
+}
+
+static void mod_update_bounds(struct module *mod)
+{
+ __mod_update_bounds(mod->module_core, mod->core_size);
+ if (mod->init_size)
+ __mod_update_bounds(mod->module_init, mod->init_size);
+}
+
+#ifdef CONFIG_KGDB_KDB
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_KGDB_KDB */
+
+static void module_assert_mutex(void)
+{
+ lockdep_assert_held(&module_mutex);
+}
+
+static void module_assert_mutex_or_preempt(void)
+{
+#ifdef CONFIG_LOCKDEP
+ if (unlikely(!debug_locks))
+ return;
+
+ WARN_ON(!rcu_read_lock_sched_held() &&
+ !lockdep_is_held(&module_mutex));
+#endif
+}
+
+static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
+#ifndef CONFIG_MODULE_SIG_FORCE
module_param(sig_enforce, bool_enable_only, 0644);
#endif /* !CONFIG_MODULE_SIG_FORCE */
-#endif /* CONFIG_MODULE_SIG */
/* Block module loading/unloading? */
int modules_disabled = 0;
@@ -153,10 +306,6 @@ static DECLARE_WAIT_QUEUE_HEAD(module_wq);
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
-/* Bounds of module allocation, for speeding __module_address.
- * Protected by module_mutex. */
-static unsigned long module_addr_min = -1UL, module_addr_max = 0;
-
int register_module_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&module_notify_list, nb);
@@ -318,6 +467,8 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
#endif
};
+ module_assert_mutex_or_preempt();
+
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
return true;
@@ -457,6 +608,8 @@ static struct module *find_module_all(const char *name, size_t len,
{
struct module *mod;
+ module_assert_mutex();
+
list_for_each_entry(mod, &modules, list) {
if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
continue;
@@ -1169,11 +1322,17 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
{
const unsigned long *crc;
- /* Since this should be found in kernel (which can't be removed),
- * no locking is necessary. */
+ /*
+ * Since this should be found in kernel (which can't be removed), no
+ * locking is necessary -- use preempt_disable() to placate lockdep.
+ */
+ preempt_disable();
if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
- &crc, true, false))
+ &crc, true, false)) {
+ preempt_enable();
BUG();
+ }
+ preempt_enable();
return check_version(sechdrs, versindex,
VMLINUX_SYMBOL_STR(module_layout), mod, crc,
NULL);
@@ -1661,6 +1820,10 @@ static void mod_sysfs_fini(struct module *mod)
mod_kobject_put(mod);
}
+static void init_param_lock(struct module *mod)
+{
+ mutex_init(&mod->param_lock);
+}
#else /* !CONFIG_SYSFS */
static int mod_sysfs_setup(struct module *mod,
@@ -1683,6 +1846,9 @@ static void del_usage_links(struct module *mod)
{
}
+static void init_param_lock(struct module *mod)
+{
+}
#endif /* CONFIG_SYSFS */
static void mod_sysfs_teardown(struct module *mod)
@@ -1852,10 +2018,11 @@ static void free_module(struct module *mod)
mutex_lock(&module_mutex);
/* Unlink carefully: kallsyms could be walking list. */
list_del_rcu(&mod->list);
+ mod_tree_remove(mod);
/* Remove this module from bug list, this uses list_del_rcu */
module_bug_cleanup(mod);
- /* Wait for RCU synchronizing before releasing mod->list and buglist. */
- synchronize_rcu();
+ /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
+ synchronize_sched();
mutex_unlock(&module_mutex);
/* This may be NULL, but that's OK */
@@ -2384,22 +2551,6 @@ void * __weak module_alloc(unsigned long size)
return vmalloc_exec(size);
}
-static void *module_alloc_update_bounds(unsigned long size)
-{
- void *ret = module_alloc(size);
-
- if (ret) {
- mutex_lock(&module_mutex);
- /* Update module bounds. */
- if ((unsigned long)ret < module_addr_min)
- module_addr_min = (unsigned long)ret;
- if ((unsigned long)ret + size > module_addr_max)
- module_addr_max = (unsigned long)ret + size;
- mutex_unlock(&module_mutex);
- }
- return ret;
-}
-
#ifdef CONFIG_DEBUG_KMEMLEAK
static void kmemleak_load_module(const struct module *mod,
const struct load_info *info)
@@ -2805,7 +2956,7 @@ static int move_module(struct module *mod, struct load_info *info)
void *ptr;
/* Do the allocs. */
- ptr = module_alloc_update_bounds(mod->core_size);
+ ptr = module_alloc(mod->core_size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. Just mark it as not being a
@@ -2819,7 +2970,7 @@ static int move_module(struct module *mod, struct load_info *info)
mod->module_core = ptr;
if (mod->init_size) {
- ptr = module_alloc_update_bounds(mod->init_size);
+ ptr = module_alloc(mod->init_size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. This block doesn't need to be
@@ -3119,6 +3270,7 @@ static noinline int do_init_module(struct module *mod)
mod->symtab = mod->core_symtab;
mod->strtab = mod->core_strtab;
#endif
+ mod_tree_remove_init(mod);
unset_module_init_ro_nx(mod);
module_arch_freeing_init(mod);
mod->module_init = NULL;
@@ -3127,11 +3279,11 @@ static noinline int do_init_module(struct module *mod)
mod->init_text_size = 0;
/*
* We want to free module_init, but be aware that kallsyms may be
- * walking this with preempt disabled. In all the failure paths,
- * we call synchronize_rcu/synchronize_sched, but we don't want
- * to slow down the success path, so use actual RCU here.
+ * walking this with preempt disabled. In all the failure paths, we
+ * call synchronize_sched(), but we don't want to slow down the success
+ * path, so use actual RCU here.
*/
- call_rcu(&freeinit->rcu, do_free_init);
+ call_rcu_sched(&freeinit->rcu, do_free_init);
mutex_unlock(&module_mutex);
wake_up_all(&module_wq);
@@ -3188,7 +3340,9 @@ again:
err = -EEXIST;
goto out;
}
+ mod_update_bounds(mod);
list_add_rcu(&mod->list, &modules);
+ mod_tree_insert(mod);
err = 0;
out:
@@ -3304,6 +3458,8 @@ static int load_module(struct load_info *info, const char __user *uargs,
if (err)
goto unlink_mod;
+ init_param_lock(mod);
+
/* Now we've got everything in the final locations, we can
* find optional sections. */
err = find_module_sections(mod, info);
@@ -3402,8 +3558,8 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Unlink carefully: kallsyms could be walking list. */
list_del_rcu(&mod->list);
wake_up_all(&module_wq);
- /* Wait for RCU synchronizing before releasing mod->list. */
- synchronize_rcu();
+ /* Wait for RCU-sched synchronizing before releasing mod->list. */
+ synchronize_sched();
mutex_unlock(&module_mutex);
free_module:
/* Free lock-classes; relies on the preceding sync_rcu() */
@@ -3527,19 +3683,15 @@ const char *module_address_lookup(unsigned long addr,
char **modname,
char *namebuf)
{
- struct module *mod;
const char *ret = NULL;
+ struct module *mod;
preempt_disable();
- list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- if (within_module(addr, mod)) {
- if (modname)
- *modname = mod->name;
- ret = get_ksymbol(mod, addr, size, offset);
- break;
- }
+ mod = __module_address(addr);
+ if (mod) {
+ if (modname)
+ *modname = mod->name;
+ ret = get_ksymbol(mod, addr, size, offset);
}
/* Make a copy in here where it's safe */
if (ret) {
@@ -3547,6 +3699,7 @@ const char *module_address_lookup(unsigned long addr,
ret = namebuf;
}
preempt_enable();
+
return ret;
}
@@ -3670,6 +3823,8 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
unsigned int i;
int ret;
+ module_assert_mutex();
+
list_for_each_entry(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
continue;
@@ -3844,13 +3999,15 @@ struct module *__module_address(unsigned long addr)
if (addr < module_addr_min || addr > module_addr_max)
return NULL;
- list_for_each_entry_rcu(mod, &modules, list) {
+ module_assert_mutex_or_preempt();
+
+ mod = mod_find(addr);
+ if (mod) {
+ BUG_ON(!within_module(addr, mod));
if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- if (within_module(addr, mod))
- return mod;
+ mod = NULL;
}
- return NULL;
+ return mod;
}
EXPORT_SYMBOL_GPL(__module_address);
diff --git a/kernel/params.c b/kernel/params.c
index 30288c1e15dd..b6554aa71094 100644
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -25,15 +25,34 @@
#include <linux/slab.h>
#include <linux/ctype.h>
-/* Protects all parameters, and incidentally kmalloced_param list. */
+#ifdef CONFIG_SYSFS
+/* Protects all built-in parameters, modules use their own param_lock */
static DEFINE_MUTEX(param_lock);
+/* Use the module's mutex, or if built-in use the built-in mutex */
+#ifdef CONFIG_MODULES
+#define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : &param_lock)
+#else
+#define KPARAM_MUTEX(mod) (&param_lock)
+#endif
+
+static inline void check_kparam_locked(struct module *mod)
+{
+ BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod)));
+}
+#else
+static inline void check_kparam_locked(struct module *mod)
+{
+}
+#endif /* !CONFIG_SYSFS */
+
/* This just allows us to keep track of which parameters are kmalloced. */
struct kmalloced_param {
struct list_head list;
char val[];
};
static LIST_HEAD(kmalloced_params);
+static DEFINE_SPINLOCK(kmalloced_params_lock);
static void *kmalloc_parameter(unsigned int size)
{
@@ -43,7 +62,10 @@ static void *kmalloc_parameter(unsigned int size)
if (!p)
return NULL;
+ spin_lock(&kmalloced_params_lock);
list_add(&p->list, &kmalloced_params);
+ spin_unlock(&kmalloced_params_lock);
+
return p->val;
}
@@ -52,6 +74,7 @@ static void maybe_kfree_parameter(void *param)
{
struct kmalloced_param *p;
+ spin_lock(&kmalloced_params_lock);
list_for_each_entry(p, &kmalloced_params, list) {
if (p->val == param) {
list_del(&p->list);
@@ -59,6 +82,7 @@ static void maybe_kfree_parameter(void *param)
break;
}
}
+ spin_unlock(&kmalloced_params_lock);
}
static char dash2underscore(char c)
@@ -119,10 +143,10 @@ static int parse_one(char *param,
return -EINVAL;
pr_debug("handling %s with %p\n", param,
params[i].ops->set);
- mutex_lock(&param_lock);
+ kernel_param_lock(params[i].mod);
param_check_unsafe(&params[i]);
err = params[i].ops->set(val, &params[i]);
- mutex_unlock(&param_lock);
+ kernel_param_unlock(params[i].mod);
return err;
}
}
@@ -254,7 +278,7 @@ char *parse_args(const char *doing,
return scnprintf(buffer, PAGE_SIZE, format, \
*((type *)kp->arg)); \
} \
- struct kernel_param_ops param_ops_##name = { \
+ const struct kernel_param_ops param_ops_##name = { \
.set = param_set_##name, \
.get = param_get_##name, \
}; \
@@ -306,7 +330,7 @@ static void param_free_charp(void *arg)
maybe_kfree_parameter(*((char **)arg));
}
-struct kernel_param_ops param_ops_charp = {
+const struct kernel_param_ops param_ops_charp = {
.set = param_set_charp,
.get = param_get_charp,
.free = param_free_charp,
@@ -331,13 +355,44 @@ int param_get_bool(char *buffer, const struct kernel_param *kp)
}
EXPORT_SYMBOL(param_get_bool);
-struct kernel_param_ops param_ops_bool = {
+const struct kernel_param_ops param_ops_bool = {
.flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_bool,
.get = param_get_bool,
};
EXPORT_SYMBOL(param_ops_bool);
+int param_set_bool_enable_only(const char *val, const struct kernel_param *kp)
+{
+ int err = 0;
+ bool new_value;
+ bool orig_value = *(bool *)kp->arg;
+ struct kernel_param dummy_kp = *kp;
+
+ dummy_kp.arg = &new_value;
+
+ err = param_set_bool(val, &dummy_kp);
+ if (err)
+ return err;
+
+ /* Don't let them unset it once it's set! */
+ if (!new_value && orig_value)
+ return -EROFS;
+
+ if (new_value)
+ err = param_set_bool(val, kp);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(param_set_bool_enable_only);
+
+const struct kernel_param_ops param_ops_bool_enable_only = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_bool_enable_only,
+ .get = param_get_bool,
+};
+EXPORT_SYMBOL_GPL(param_ops_bool_enable_only);
+
/* This one must be bool. */
int param_set_invbool(const char *val, const struct kernel_param *kp)
{
@@ -359,7 +414,7 @@ int param_get_invbool(char *buffer, const struct kernel_param *kp)
}
EXPORT_SYMBOL(param_get_invbool);
-struct kernel_param_ops param_ops_invbool = {
+const struct kernel_param_ops param_ops_invbool = {
.set = param_set_invbool,
.get = param_get_invbool,
};
@@ -367,12 +422,11 @@ EXPORT_SYMBOL(param_ops_invbool);
int param_set_bint(const char *val, const struct kernel_param *kp)
{
- struct kernel_param boolkp;
+ /* Match bool exactly, by re-using it. */
+ struct kernel_param boolkp = *kp;
bool v;
int ret;
- /* Match bool exactly, by re-using it. */
- boolkp = *kp;
boolkp.arg = &v;
ret = param_set_bool(val, &boolkp);
@@ -382,7 +436,7 @@ int param_set_bint(const char *val, const struct kernel_param *kp)
}
EXPORT_SYMBOL(param_set_bint);
-struct kernel_param_ops param_ops_bint = {
+const struct kernel_param_ops param_ops_bint = {
.flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_bint,
.get = param_get_int,
@@ -390,7 +444,8 @@ struct kernel_param_ops param_ops_bint = {
EXPORT_SYMBOL(param_ops_bint);
/* We break the rule and mangle the string. */
-static int param_array(const char *name,
+static int param_array(struct module *mod,
+ const char *name,
const char *val,
unsigned int min, unsigned int max,
void *elem, int elemsize,
@@ -421,7 +476,7 @@ static int param_array(const char *name,
/* nul-terminate and parse */
save = val[len];
((char *)val)[len] = '\0';
- BUG_ON(!mutex_is_locked(&param_lock));
+ check_kparam_locked(mod);
ret = set(val, &kp);
if (ret != 0)
@@ -443,7 +498,7 @@ static int param_array_set(const char *val, const struct kernel_param *kp)
const struct kparam_array *arr = kp->arr;
unsigned int temp_num;
- return param_array(kp->name, val, 1, arr->max, arr->elem,
+ return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem,
arr->elemsize, arr->ops->set, kp->level,
arr->num ?: &temp_num);
}
@@ -452,14 +507,13 @@ static int param_array_get(char *buffer, const struct kernel_param *kp)
{
int i, off, ret;
const struct kparam_array *arr = kp->arr;
- struct kernel_param p;
+ struct kernel_param p = *kp;
- p = *kp;
for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
if (i)
buffer[off++] = ',';
p.arg = arr->elem + arr->elemsize * i;
- BUG_ON(!mutex_is_locked(&param_lock));
+ check_kparam_locked(p.mod);
ret = arr->ops->get(buffer + off, &p);
if (ret < 0)
return ret;
@@ -479,7 +533,7 @@ static void param_array_free(void *arg)
arr->ops->free(arr->elem + arr->elemsize * i);
}
-struct kernel_param_ops param_array_ops = {
+const struct kernel_param_ops param_array_ops = {
.set = param_array_set,
.get = param_array_get,
.free = param_array_free,
@@ -507,7 +561,7 @@ int param_get_string(char *buffer, const struct kernel_param *kp)
}
EXPORT_SYMBOL(param_get_string);
-struct kernel_param_ops param_ops_string = {
+const struct kernel_param_ops param_ops_string = {
.set = param_set_copystring,
.get = param_get_string,
};
@@ -542,9 +596,9 @@ static ssize_t param_attr_show(struct module_attribute *mattr,
if (!attribute->param->ops->get)
return -EPERM;
- mutex_lock(&param_lock);
+ kernel_param_lock(mk->mod);
count = attribute->param->ops->get(buf, attribute->param);
- mutex_unlock(&param_lock);
+ kernel_param_unlock(mk->mod);
if (count > 0) {
strcat(buf, "\n");
++count;
@@ -554,7 +608,7 @@ static ssize_t param_attr_show(struct module_attribute *mattr,
/* sysfs always hands a nul-terminated string in buf. We rely on that. */
static ssize_t param_attr_store(struct module_attribute *mattr,
- struct module_kobject *km,
+ struct module_kobject *mk,
const char *buf, size_t len)
{
int err;
@@ -563,10 +617,10 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
if (!attribute->param->ops->set)
return -EPERM;
- mutex_lock(&param_lock);
+ kernel_param_lock(mk->mod);
param_check_unsafe(attribute->param);
err = attribute->param->ops->set(buf, attribute->param);
- mutex_unlock(&param_lock);
+ kernel_param_unlock(mk->mod);
if (!err)
return len;
return err;
@@ -580,17 +634,18 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
#endif
#ifdef CONFIG_SYSFS
-void __kernel_param_lock(void)
+void kernel_param_lock(struct module *mod)
{
- mutex_lock(&param_lock);
+ mutex_lock(KPARAM_MUTEX(mod));
}
-EXPORT_SYMBOL(__kernel_param_lock);
-void __kernel_param_unlock(void)
+void kernel_param_unlock(struct module *mod)
{
- mutex_unlock(&param_lock);
+ mutex_unlock(KPARAM_MUTEX(mod));
}
-EXPORT_SYMBOL(__kernel_param_unlock);
+
+EXPORT_SYMBOL(kernel_param_lock);
+EXPORT_SYMBOL(kernel_param_unlock);
/*
* add_sysfs_param - add a parameter to sysfs
@@ -856,6 +911,7 @@ static void __init version_sysfs_builtin(void)
mk = locate_module_kobject(vattr->module_name);
if (mk) {
err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
+ WARN_ON_ONCE(err);
kobject_uevent(&mk->kobj, KOBJ_ADD);
kobject_put(&mk->kobj);
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 30b7a409bf1e..bca3667a2de1 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -319,32 +319,7 @@ static inline s64 timekeeping_get_ns(struct tk_read_base *tkr)
* We want to use this from any context including NMI and tracing /
* instrumenting the timekeeping code itself.
*
- * So we handle this differently than the other timekeeping accessor
- * functions which retry when the sequence count has changed. The
- * update side does:
- *
- * smp_wmb(); <- Ensure that the last base[1] update is visible
- * tkf->seq++;
- * smp_wmb(); <- Ensure that the seqcount update is visible
- * update(tkf->base[0], tkr);
- * smp_wmb(); <- Ensure that the base[0] update is visible
- * tkf->seq++;
- * smp_wmb(); <- Ensure that the seqcount update is visible
- * update(tkf->base[1], tkr);
- *
- * The reader side does:
- *
- * do {
- * seq = tkf->seq;
- * smp_rmb();
- * idx = seq & 0x01;
- * now = now(tkf->base[idx]);
- * smp_rmb();
- * } while (seq != tkf->seq)
- *
- * As long as we update base[0] readers are forced off to
- * base[1]. Once base[0] is updated readers are redirected to base[0]
- * and the base[1] update takes place.
+ * Employ the latch technique; see @raw_write_seqcount_latch.
*
* So if a NMI hits the update of base[0] then it will use base[1]
* which is still consistent. In the worst case this can result is a
@@ -407,7 +382,7 @@ static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf)
u64 now;
do {
- seq = raw_read_seqcount(&tkf->seq);
+ seq = raw_read_seqcount_latch(&tkf->seq);
tkr = tkf->base + (seq & 0x01);
now = ktime_to_ns(tkr->base) + timekeeping_get_ns(tkr);
} while (read_seqcount_retry(&tkf->seq, seq));
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5243d4b03087..4c4f06176f74 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -285,12 +285,7 @@ static bool wq_disable_numa;
module_param_named(disable_numa, wq_disable_numa, bool, 0444);
/* see the comment above the definition of WQ_POWER_EFFICIENT */
-#ifdef CONFIG_WQ_POWER_EFFICIENT_DEFAULT
-static bool wq_power_efficient = true;
-#else
-static bool wq_power_efficient;
-#endif
-
+static bool wq_power_efficient = IS_ENABLED(CONFIG_WQ_POWER_EFFICIENT_DEFAULT);
module_param_named(power_efficient, wq_power_efficient, bool, 0444);
static bool wq_numa_enabled; /* unbound NUMA affinity enabled */
diff --git a/lib/bug.c b/lib/bug.c
index 0c3bd9552b6f..cff145f032a5 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -66,7 +66,7 @@ static const struct bug_entry *module_find_bug(unsigned long bugaddr)
struct module *mod;
const struct bug_entry *bug = NULL;
- rcu_read_lock();
+ rcu_read_lock_sched();
list_for_each_entry_rcu(mod, &module_bug_list, bug_list) {
unsigned i;
@@ -77,7 +77,7 @@ static const struct bug_entry *module_find_bug(unsigned long bugaddr)
}
bug = NULL;
out:
- rcu_read_unlock();
+ rcu_read_unlock_sched();
return bug;
}
@@ -88,6 +88,8 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
char *secstrings;
unsigned int i;
+ lockdep_assert_held(&module_mutex);
+
mod->bug_table = NULL;
mod->num_bugs = 0;
@@ -113,6 +115,7 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
void module_bug_cleanup(struct module *mod)
{
+ lockdep_assert_held(&module_mutex);
list_del_rcu(&mod->bug_list);
}
diff --git a/lib/rbtree.c b/lib/rbtree.c
index c16c81a3d430..1356454e36de 100644
--- a/lib/rbtree.c
+++ b/lib/rbtree.c
@@ -44,6 +44,30 @@
* parentheses and have some accompanying text comment.
*/
+/*
+ * Notes on lockless lookups:
+ *
+ * All stores to the tree structure (rb_left and rb_right) must be done using
+ * WRITE_ONCE(). And we must not inadvertently cause (temporary) loops in the
+ * tree structure as seen in program order.
+ *
+ * These two requirements will allow lockless iteration of the tree -- not
+ * correct iteration mind you, tree rotations are not atomic so a lookup might
+ * miss entire subtrees.
+ *
+ * But they do guarantee that any such traversal will only see valid elements
+ * and that it will indeed complete -- does not get stuck in a loop.
+ *
+ * It also guarantees that if the lookup returns an element it is the 'correct'
+ * one. But not returning an element does _NOT_ mean it's not present.
+ *
+ * NOTE:
+ *
+ * Stores to __rb_parent_color are not important for simple lookups so those
+ * are left undone as of now. Nor did I check for loops involving parent
+ * pointers.
+ */
+
static inline void rb_set_black(struct rb_node *rb)
{
rb->__rb_parent_color |= RB_BLACK;
@@ -129,8 +153,9 @@ __rb_insert(struct rb_node *node, struct rb_root *root,
* This still leaves us in violation of 4), the
* continuation into Case 3 will fix that.
*/
- parent->rb_right = tmp = node->rb_left;
- node->rb_left = parent;
+ tmp = node->rb_left;
+ WRITE_ONCE(parent->rb_right, tmp);
+ WRITE_ONCE(node->rb_left, parent);
if (tmp)
rb_set_parent_color(tmp, parent,
RB_BLACK);
@@ -149,8 +174,8 @@ __rb_insert(struct rb_node *node, struct rb_root *root,
* / \
* n U
*/
- gparent->rb_left = tmp; /* == parent->rb_right */
- parent->rb_right = gparent;
+ WRITE_ONCE(gparent->rb_left, tmp); /* == parent->rb_right */
+ WRITE_ONCE(parent->rb_right, gparent);
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
@@ -171,8 +196,9 @@ __rb_insert(struct rb_node *node, struct rb_root *root,
tmp = parent->rb_left;
if (node == tmp) {
/* Case 2 - right rotate at parent */
- parent->rb_left = tmp = node->rb_right;
- node->rb_right = parent;
+ tmp = node->rb_right;
+ WRITE_ONCE(parent->rb_left, tmp);
+ WRITE_ONCE(node->rb_right, parent);
if (tmp)
rb_set_parent_color(tmp, parent,
RB_BLACK);
@@ -183,8 +209,8 @@ __rb_insert(struct rb_node *node, struct rb_root *root,
}
/* Case 3 - left rotate at gparent */
- gparent->rb_right = tmp; /* == parent->rb_left */
- parent->rb_left = gparent;
+ WRITE_ONCE(gparent->rb_right, tmp); /* == parent->rb_left */
+ WRITE_ONCE(parent->rb_left, gparent);
if (tmp)
rb_set_parent_color(tmp, gparent, RB_BLACK);
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
@@ -224,8 +250,9 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
* / \ / \
* Sl Sr N Sl
*/
- parent->rb_right = tmp1 = sibling->rb_left;
- sibling->rb_left = parent;
+ tmp1 = sibling->rb_left;
+ WRITE_ONCE(parent->rb_right, tmp1);
+ WRITE_ONCE(sibling->rb_left, parent);
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
@@ -275,9 +302,10 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
* \
* Sr
*/
- sibling->rb_left = tmp1 = tmp2->rb_right;
- tmp2->rb_right = sibling;
- parent->rb_right = tmp2;
+ tmp1 = tmp2->rb_right;
+ WRITE_ONCE(sibling->rb_left, tmp1);
+ WRITE_ONCE(tmp2->rb_right, sibling);
+ WRITE_ONCE(parent->rb_right, tmp2);
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
@@ -297,8 +325,9 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
* / \ / \
* (sl) sr N (sl)
*/
- parent->rb_right = tmp2 = sibling->rb_left;
- sibling->rb_left = parent;
+ tmp2 = sibling->rb_left;
+ WRITE_ONCE(parent->rb_right, tmp2);
+ WRITE_ONCE(sibling->rb_left, parent);
rb_set_parent_color(tmp1, sibling, RB_BLACK);
if (tmp2)
rb_set_parent(tmp2, parent);
@@ -310,8 +339,9 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
sibling = parent->rb_left;
if (rb_is_red(sibling)) {
/* Case 1 - right rotate at parent */
- parent->rb_left = tmp1 = sibling->rb_right;
- sibling->rb_right = parent;
+ tmp1 = sibling->rb_right;
+ WRITE_ONCE(parent->rb_left, tmp1);
+ WRITE_ONCE(sibling->rb_right, parent);
rb_set_parent_color(tmp1, parent, RB_BLACK);
__rb_rotate_set_parents(parent, sibling, root,
RB_RED);
@@ -336,9 +366,10 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
break;
}
/* Case 3 - right rotate at sibling */
- sibling->rb_right = tmp1 = tmp2->rb_left;
- tmp2->rb_left = sibling;
- parent->rb_left = tmp2;
+ tmp1 = tmp2->rb_left;
+ WRITE_ONCE(sibling->rb_right, tmp1);
+ WRITE_ONCE(tmp2->rb_left, sibling);
+ WRITE_ONCE(parent->rb_left, tmp2);
if (tmp1)
rb_set_parent_color(tmp1, sibling,
RB_BLACK);
@@ -347,8 +378,9 @@ ____rb_erase_color(struct rb_node *parent, struct rb_root *root,
sibling = tmp2;
}
/* Case 4 - left rotate at parent + color flips */
- parent->rb_left = tmp2 = sibling->rb_right;
- sibling->rb_right = parent;
+ tmp2 = sibling->rb_right;
+ WRITE_ONCE(parent->rb_left, tmp2);
+ WRITE_ONCE(sibling->rb_right, parent);
rb_set_parent_color(tmp1, sibling, RB_BLACK);
if (tmp2)
rb_set_parent(tmp2, parent);
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 36ba7c4f0283..fda33f961d83 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -103,7 +103,7 @@ ieee80211_rate_control_ops_get(const char *name)
const struct rate_control_ops *ops;
const char *alg_name;
- kparam_block_sysfs_write(ieee80211_default_rc_algo);
+ kernel_param_lock(THIS_MODULE);
if (!name)
alg_name = ieee80211_default_rc_algo;
else
@@ -117,7 +117,7 @@ ieee80211_rate_control_ops_get(const char *name)
/* try built-in one if specific alg requested but not found */
if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT))
ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
- kparam_unblock_sysfs_write(ieee80211_default_rc_algo);
+ kernel_param_unlock(THIS_MODULE);
return ops;
}
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 47f38be4155f..02f53674dc39 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -72,7 +72,7 @@ static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp)
#define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int);
-static struct kernel_param_ops param_ops_hashtbl_sz = {
+static const struct kernel_param_ops param_ops_hashtbl_sz = {
.set = param_set_hashtbl_sz,
.get = param_get_hashtbl_sz,
};
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 66891e32c5e3..b0517287075b 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2982,7 +2982,7 @@ static int param_set_portnr(const char *val, const struct kernel_param *kp)
RPC_MAX_RESVPORT);
}
-static struct kernel_param_ops param_ops_portnr = {
+static const struct kernel_param_ops param_ops_portnr = {
.set = param_set_portnr,
.get = param_get_uint,
};
@@ -3001,7 +3001,7 @@ static int param_set_slot_table_size(const char *val,
RPC_MAX_SLOT_TABLE);
}
-static struct kernel_param_ops param_ops_slot_table_size = {
+static const struct kernel_param_ops param_ops_slot_table_size = {
.set = param_set_slot_table_size,
.get = param_get_uint,
};
@@ -3017,7 +3017,7 @@ static int param_set_max_slot_table_size(const char *val,
RPC_MAX_SLOT_TABLE_LIMIT);
}
-static struct kernel_param_ops param_ops_max_slot_table_size = {
+static const struct kernel_param_ops param_ops_max_slot_table_size = {
.set = param_set_max_slot_table_size,
.get = param_get_uint,
};
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 5696874e8062..dec607c17b64 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -654,7 +654,7 @@ static struct security_hook_list apparmor_hooks[] = {
static int param_set_aabool(const char *val, const struct kernel_param *kp);
static int param_get_aabool(char *buffer, const struct kernel_param *kp);
#define param_check_aabool param_check_bool
-static struct kernel_param_ops param_ops_aabool = {
+static const struct kernel_param_ops param_ops_aabool = {
.flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_aabool,
.get = param_get_aabool
@@ -663,7 +663,7 @@ static struct kernel_param_ops param_ops_aabool = {
static int param_set_aauint(const char *val, const struct kernel_param *kp);
static int param_get_aauint(char *buffer, const struct kernel_param *kp);
#define param_check_aauint param_check_uint
-static struct kernel_param_ops param_ops_aauint = {
+static const struct kernel_param_ops param_ops_aauint = {
.set = param_set_aauint,
.get = param_get_aauint
};
@@ -671,7 +671,7 @@ static struct kernel_param_ops param_ops_aauint = {
static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
#define param_check_aalockpolicy param_check_bool
-static struct kernel_param_ops param_ops_aalockpolicy = {
+static const struct kernel_param_ops param_ops_aalockpolicy = {
.flags = KERNEL_PARAM_OPS_FL_NOARG,
.set = param_set_aalockpolicy,
.get = param_get_aalockpolicy
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 686355fea7fd..e24121afb2f2 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -55,7 +55,7 @@ static int param_set_bufsize(const char *val, const struct kernel_param *kp)
return 0;
}
-static struct kernel_param_ops param_ops_bufsize = {
+static const struct kernel_param_ops param_ops_bufsize = {
.set = param_set_bufsize,
.get = param_get_uint,
};
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 7dea7987d2af..9913e24d6699 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -171,7 +171,7 @@ MODULE_PARM_DESC(beep_mode, "Select HDA Beep registration mode "
#ifdef CONFIG_PM
static int param_set_xint(const char *val, const struct kernel_param *kp);
-static struct kernel_param_ops param_ops_xint = {
+static const struct kernel_param_ops param_ops_xint = {
.set = param_set_xint,
.get = param_get_int,
};