| Commit message (Collapse) | Author | Age | Files | Lines |
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Misc fixlets"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/cputime: Fix accounting on multi-threaded processes
sched/debug: Fix sd->*_idx limit range avoiding overflow
sched_clock: Prevent 64bit inatomicity on 32bit systems
sched: Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s
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Recent commit 6fac4829 ("cputime: Use accessors to read task
cputime stats") introduced a bug, where we account many times
the cputime of the first thread, instead of cputimes of all
the different threads.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130404085740.GA2495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Commit 201c373e8e ("sched/debug: Limit sd->*_idx range on
sysctl") was an incomplete bug fix.
This patch fixes sd->*_idx limit range to [0 ~ CPU_LOAD_IDX_MAX-1]
avoiding array overflow caused by setting sd->*_idx to CPU_LOAD_IDX_MAX
on sysctl.
Signed-off-by: Libin <huawei.libin@huawei.com>
Cc: <jiang.liu@huawei.com>
Cc: <guohanjun@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/51626610.2040607@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The sched_clock_remote() implementation has the following inatomicity
problem on 32bit systems when accessing the remote scd->clock, which
is a 64bit value.
CPU0 CPU1
sched_clock_local() sched_clock_remote(CPU0)
...
remote_clock = scd[CPU0]->clock
read_low32bit(scd[CPU0]->clock)
cmpxchg64(scd->clock,...)
read_high32bit(scd[CPU0]->clock)
While the update of scd->clock is using an atomic64 mechanism, the
readout on the remote cpu is not, which can cause completely bogus
readouts.
It is a quite rare problem, because it requires the update to hit the
narrow race window between the low/high readout and the update must go
across the 32bit boundary.
The resulting misbehaviour is, that CPU1 will see the sched_clock on
CPU1 ~4 seconds ahead of it's own and update CPU1s sched_clock value
to this bogus timestamp. This stays that way due to the clamping
implementation for about 4 seconds until the synchronization with
CLOCK_MONOTONIC undoes the problem.
The issue is hard to observe, because it might only result in a less
accurate SCHED_OTHER timeslicing behaviour. To create observable
damage on realtime scheduling classes, it is necessary that the bogus
update of CPU1 sched_clock happens in the context of an realtime
thread, which then gets charged 4 seconds of RT runtime, which results
in the RT throttler mechanism to trigger and prevent scheduling of RT
tasks for a little less than 4 seconds. So this is quite unlikely as
well.
The issue was quite hard to decode as the reproduction time is between
2 days and 3 weeks and intrusive tracing makes it less likely, but the
following trace recorded with trace_clock=global, which uses
sched_clock_local(), gave the final hint:
<idle>-0 0d..30 400269.477150: hrtimer_cancel: hrtimer=0xf7061e80
<idle>-0 0d..30 400269.477151: hrtimer_start: hrtimer=0xf7061e80 ...
irq/20-S-587 1d..32 400273.772118: sched_wakeup: comm= ... target_cpu=0
<idle>-0 0dN.30 400273.772118: hrtimer_cancel: hrtimer=0xf7061e80
What happens is that CPU0 goes idle and invokes
sched_clock_idle_sleep_event() which invokes sched_clock_local() and
CPU1 runs a remote wakeup for CPU0 at the same time, which invokes
sched_remote_clock(). The time jump gets propagated to CPU0 via
sched_remote_clock() and stays stale on both cores for ~4 seconds.
There are only two other possibilities, which could cause a stale
sched clock:
1) ktime_get() which reads out CLOCK_MONOTONIC returns a sporadic
wrong value.
2) sched_clock() which reads the TSC returns a sporadic wrong value.
#1 can be excluded because sched_clock would continue to increase for
one jiffy and then go stale.
#2 can be excluded because it would not make the clock jump
forward. It would just result in a stale sched_clock for one jiffy.
After quite some brain twisting and finding the same pattern on other
traces, sched_clock_remote() remained the only place which could cause
such a problem and as explained above it's indeed racy on 32bit
systems.
So while on 64bit systems the readout is atomic, we need to verify the
remote readout on 32bit machines. We need to protect the local->clock
readout in sched_clock_remote() on 32bit as well because an NMI could
hit between the low and the high readout, call sched_clock_local() and
modify local->clock.
Thanks to Siegfried Wulsch for bearing with my debug requests and
going through the tedious tasks of running a bunch of reproducer
systems to generate the debug information which let me decode the
issue.
Reported-by: Siegfried Wulsch <Siegfried.Wulsch@rovema.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304051544160.21884@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
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try_to_wake_up_local() should only be invoked to wake up another
task in the same runqueue and BUG_ON()s are used to enforce the
rule. Missing try_to_wake_up_local() can stall workqueue
execution but such stalls are likely to be finite either by
another work item being queued or the one blocked getting
unblocked. There's no reason to trigger BUG while holding rq
lock crashing the whole system.
Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130318192234.GD3042@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Misc fixlets"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix error return code
ftrace: Fix strncpy() use, use strlcpy() instead of strncpy()
perf: Fix strncpy() use, use strlcpy() instead of strncpy()
perf: Fix strncpy() use, always make sure it's NUL terminated
perf: Fix ring_buffer perf_output_space() boundary calculation
perf/x86: Fix uninitialized pt_regs in intel_pmu_drain_bts_buffer()
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Fix to return -ENOMEM in the allocation error case instead of 0
(if pmu_bus_running == 1), as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: acme@ghostprotocols.net
Link: http://lkml.kernel.org/r/CAPgLHd8j_fWcgqe%3DKLWjpBj%2B%3Do0Pw6Z-SEq%3DNTPU08c2w1tngQ@mail.gmail.com
[ Tweaked the error code setting placement and the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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For NUL terminated string we always need to set '\0' at the end.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: rostedt@goodmis.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/516243B7.9020405@asianux.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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For NUL terminated string we always need to set '\0' at the end.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: rostedt@goodmis.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/51624254.30301@asianux.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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For NUL terminated string, always make sure that there's '\0' at the end.
In our case we need a return value, so still use strncpy() and
fix up the tail explicitly.
(strlcpy() returns the size, not the pointer)
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: a.p.zijlstra@chello.nl <a.p.zijlstra@chello.nl>
Cc: paulus@samba.org <paulus@samba.org>
Cc: acme@ghostprotocols.net <acme@ghostprotocols.net>
Link: http://lkml.kernel.org/r/51623E0B.7070101@asianux.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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This patch fixes a flaw in perf_output_space(). In case the size
of the space needed is bigger than the actual buffer size, there
may be situations where the function would return true (i.e.,
there is space) when it should not. head > offset due to
rounding of the masking logic.
The problem can be tested by activating BTS on Intel processors.
A BTS record can be as big as 16 pages. The following command
fails:
$ perf record -m 4 -c 1 -e branches:u my_test_program
You will get a buffer corruption with this. Perf report won't be
able to parse the perf.data.
The fix is to first check that the requested space is smaller
than the buffer size. If so, then the masking logic will work
fine. If not, then there is no chance the record can be saved
and it will be gracefully handled by upper code layers.
[ In v2, we also make the logic for the writable more explicit by
renaming it to rb->overwrite because it tells whether or not the
buffer can overwrite its tail (suggested by PeterZ). ]
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: peterz@infradead.org
Cc: jolsa@redhat.com
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/r/20130318133327.GA3056@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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This patch fixes an uninitialized pt_regs struct in drain BTS
function. The pt_regs struct is propagated all the way to the
code_get_segment() function from perf_instruction_pointer()
and may get garbage.
We cannot simply inherit the actual pt_regs from the interrupt
because BTS must be flushed on context-switch or when the
associated event is disabled. And there we do not have a pt_regs
handy.
Setting pt_regs to all zeroes may not be the best option but it
is not clear what else to do given where the drain_bts_buffer()
is called from.
In V2, we move the memset() later in the code to avoid doing it
when we end up returning early without doing the actual BTS
processing. Also dropped the reg.val initialization because it
is redundant with the memset() as suggested by PeterZ.
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: peterz@infradead.org
Cc: sqazi@google.com
Cc: ak@linux.intel.com
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/20130319151038.GA25439@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Pull drm fixes from Dave Airlie:
"One fix for a hotplug locking regressions, and one fix for an oops if
you unplug the monitor at an inopportune moment on the udl device."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/fb-helper: Fix locking in drm_fb_helper_hotplug_event
udl: handle EDID failure properly.
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Driver's and ->fill_modes functions are allowed to grab crtc mutexes
(for e.g. load detect). Hence we need to first only grab the general
kms mutex, and only in a second step grab all locks to do the
modesets.
This prevents a deadlock on my gm45 in the tv load detect code called
by drm_helper_probe_single_connector_modes.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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Don't oops seems proper.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu fix from Greg Ungerer:
"This contains only a single compilation fix for ColdFire m68k targets
that use local non-GPIOLIB support."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: define a local gpio_request_one() function
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Compiling for linux-3.9-rc1 and later fails with:
drivers/gpio/devres.c: In function 'devm_gpio_request_one':
drivers/gpio/devres.c:90:2: error: implicit declaration of function 'gpio_request_one' [-Werror=implicit-function-declaration]
So provide a local gpio_request_one() function. Code largely borrowed from
blackfin's local gpio_request_one() function.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
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Pull watchdog fix from Wim Van Sebroeck:
"It will fix compile errors for the at91rm9200_wdt driver"
* git://www.linux-watchdog.org/linux-watchdog:
watchdog: Revert the AT91RM9200_WATCHDOG dependency
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Compiling the at91rm9200_wdt.c driver without at91rm9200
support was leading to several errors:
drivers/built-in.o: In function `at91_wdt_close':
at91_adc.c:(.text+0xc9fe4): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91_wdt_write':
at91_adc.c:(.text+0xca004): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91wdt_shutdown':
at91_adc.c:(.text+0xca01c): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91wdt_suspend':
at91_adc.c:(.text+0xca038): undefined reference to `at91_st_base'
drivers/built-in.o: In function `at91_wdt_open':
at91_adc.c:(.text+0xca0cc): undefined reference to `at91_st_base'
drivers/built-in.o:at91_adc.c:(.text+0xca2c8): more undefined references to
`at91_st_base' follow
So, reverting the modification of the "depends" Kconfig line
introduced by patch a6a1bcd37 (watchdog: at91rm9200: add DT support)
seems to be the good solution.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
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git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull one more btrfs fix from Chris Mason:
"This has a recent fix from Josef for our tree log replay code. It
fixes problems where the inode counter for the number of bytes in the
file wasn't getting updated properly during fsync replay.
The commit did get rebased this morning, but it was only to clean up
the subject line. The code hasn't changed."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: make sure nbytes are right after log replay
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While trying to track down a tree log replay bug I noticed that fsck was always
complaining about nbytes not being right for our fsynced file. That is because
the new fsync stuff doesn't wait for ordered extents to complete, so the inodes
nbytes are not necessarily updated properly when we log it. So to fix this we
need to set nbytes to whatever it is on the inode that is on disk, so when we
replay the extents we can just add the bytes that are being added as we replay
the extent. This makes it work for the case that we have the wrong nbytes or
the case that we logged everything and nbytes is actually correct. With this
I'm no longer getting nbytes errors out of btrfsck.
Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fixes from Steven Rostedt:
"Namhyung Kim found and fixed a bug that can crash the kernel by simply
doing: echo 1234 | tee -a /sys/kernel/debug/tracing/set_ftrace_pid
Luckily, this can only be done by root, but still is a nasty bug."
* tag 'trace-fixes-v3.9-rc-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Move ftrace_filter_lseek out of CONFIG_DYNAMIC_FTRACE section
tracing: Fix possible NULL pointer dereferences
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As ftrace_filter_lseek is now used with ftrace_pid_fops, it needs to
be moved out of the #ifdef CONFIG_DYNAMIC_FTRACE section as the
ftrace_pid_fops is defined when DYNAMIC_FTRACE is not.
Cc: stable@vger.kernel.org
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Currently set_ftrace_pid and set_graph_function files use seq_lseek
for their fops. However seq_open() is called only for FMODE_READ in
the fops->open() so that if an user tries to seek one of those file
when she open it for writing, it sees NULL seq_file and then panic.
It can be easily reproduced with following command:
$ cd /sys/kernel/debug/tracing
$ echo 1234 | sudo tee -a set_ftrace_pid
In this example, GNU coreutils' tee opens the file with fopen(, "a")
and then the fopen() internally calls lseek().
Link: http://lkml.kernel.org/r/1365663302-2170-1-git-send-email-namhyung@kernel.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: stable@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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Nothing is using it yet, but this will allow us to delay the open-time
checks to use time, without breaking the normal UNIX permission
semantics where permissions are determined by the opener (and the file
descriptor can then be passed to a different process, or the process can
drop capabilities).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Revert commit 62a3ddef6181 ("vfs: fix spinning prevention in prune_icache_sb").
This commit doesn't look right: since we are looking at the tail of the
list (sb->s_inode_lru.prev) if we want to skip an inode, we should put
it back at the head of the list instead of the tail, otherwise we will
keep spinning on it.
Discovered when investigating why prune_icache_sb came top in perf
reports of a swapping load.
Signed-off-by: Suleiman Souhlal <suleiman@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Anatol Pomozov identified a race condition that hits module unloading
and re-loading. To quote Anatol:
"This is a race codition that exists between kset_find_obj() and
kobject_put(). kset_find_obj() might return kobject that has refcount
equal to 0 if this kobject is freeing by kobject_put() in other
thread.
Here is timeline for the crash in case if kset_find_obj() searches for
an object tht nobody holds and other thread is doing kobject_put() on
the same kobject:
THREAD A (calls kset_find_obj()) THREAD B (calls kobject_put())
splin_lock()
atomic_dec_return(kobj->kref), counter gets zero here
... starts kobject cleanup ....
spin_lock() // WAIT thread A in kobj_kset_leave()
iterate over kset->list
atomic_inc(kobj->kref) (counter becomes 1)
spin_unlock()
spin_lock() // taken
// it does not know that thread A increased counter so it
remove obj from list
spin_unlock()
vfree(module) // frees module object with containing kobj
// kobj points to freed memory area!!
kobject_put(kobj) // OOPS!!!!
The race above happens because module.c tries to use kset_find_obj()
when somebody unloads module. The module.c code was introduced in
commit 6494a93d55fa"
Anatol supplied a patch specific for module.c that worked around the
problem by simply not using kset_find_obj() at all, but rather than make
a local band-aid, this just fixes kset_find_obj() to be thread-safe
using the proper model of refusing the get a new reference if the
refcount has already dropped to zero.
See examples of this proper refcount handling not only in the kref
documentation, but in various other equivalent uses of this pattern by
grepping for atomic_inc_not_zero().
[ Side note: the module race does indicate that module loading and
unloading is not properly serialized wrt sysfs information using the
module mutex. That may require further thought, but this is the
correct fix at the kobject layer regardless. ]
Reported-analyzed-and-tested-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch attempts to fix:
https://bugzilla.kernel.org/show_bug.cgi?id=56461
The symptom is a crash and messages like this:
chrome: Corrupted page table at address 34a03000
*pdpt = 0000000000000000 *pde = 0000000000000000
Bad pagetable: 000f [#1] PREEMPT SMP
Ingo guesses this got introduced by commit 611ae8e3f520 ("x86/tlb:
enable tlb flush range support for x86") since that code started to free
unused pagetables.
On x86-32 PAE kernels, that new code has the potential to free an entire
PMD page and will clear one of the four page-directory-pointer-table
(aka pgd_t entries).
The hardware aggressively "caches" these top-level entries and invlpg
does not actually affect the CPU's copy. If we clear one we *HAVE* to
do a full TLB flush, otherwise we might continue using a freed pmd page.
(note, we do this properly on the population side in pud_populate()).
This patch tracks whenever we clear one of these entries in the 'struct
mmu_gather', and ensures that we follow up with a full tlb flush.
BTW, I disassembled and checked that:
if (tlb->fullmm == 0)
and
if (!tlb->fullmm && !tlb->need_flush_all)
generate essentially the same code, so there should be zero impact there
to the !PAE case.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Artem S Tashkinov <t.artem@mailcity.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pull SCSI target fixes from Nicholas Bellinger:
"Here are remaining target-pending items for v3.9-rc7 code.
The tcm_vhost patches are more than I'd usually include in a -rc7
pull, but are changes required for v3.9 to work correctly with the
pending vhost-scsi-pci QEMU upstream series merge. (Paolo CC'ed)
Plus Asias's conversion to use vhost_virtqueue->private_data + RCU for
managing vhost-scsi endpoints has gotten alot of review + testing over
the past weeks, and MST has ACKed the full series.
Also, there is a target patch to fix a long-standing bug within
control CDB handling with Standby/Offline/Transition ALUA port access
states, that had been incorrectly rejecting the control CDBs required
for LUN scan to work during these port group states. CC'ing to
stable."
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target: Fix incorrect fallthrough of ALUA Standby/Offline/Transition CDBs
tcm_vhost: Send bad target to guest when cmd fails
tcm_vhost: Add vhost_scsi_send_bad_target() helper
tcm_vhost: Fix tv_cmd leak in vhost_scsi_handle_vq
tcm_vhost: Remove double check of response
tcm_vhost: Initialize vq->last_used_idx when set endpoint
tcm_vhost: Use vq->private_data to indicate if the endpoint is setup
tcm_vhost: Use ACCESS_ONCE for vs->vs_tpg[target] access
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This patch fixes a bug where a handful of informational / control CDBs
that should be allowed during ALUA access state Standby/Offline/Transition
where incorrectly returning CHECK_CONDITION + ASCQ_04H_ALUA_TG_PT_*.
This includes INQUIRY + REPORT_LUNS, which would end up preventing LUN
registration when LUN scanning occured during these ALUA access states.
Cc: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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Send bad target to guest in case:
1) we can not allocate the cmd
2) fail to submit the cmd
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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Share the send bad target code with other use cases.
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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If we fail to submit the allocated tv_vmd to tcm_vhost_submission_work,
we will leak the tv_vmd. Free tv_vmd on fail path.
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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We did the length of response check twice.
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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This patch fixes guest hang when booting seabios and guest.
[ 0.576238] scsi0 : Virtio SCSI HBA
[ 0.616754] virtio_scsi virtio1: request:id 0 is not a head!
vq->last_used_idx is initialized only when /dev/vhost-scsi is
opened or closed.
vhost_scsi_open -> vhost_dev_init() -> vhost_vq_reset()
vhost_scsi_release() -> vhost_dev_cleanup -> vhost_vq_reset()
So, when guest talks to tcm_vhost after seabios does, vq->last_used_idx
still contains the old valule for seabios. This confuses guest.
Fix this by calling vhost_init_used() to init vq->last_used_idx when
we set endpoint.
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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Currently, vs->vs_endpoint is used indicate if the endpoint is setup or
not. It is set or cleared in vhost_scsi_set_endpoint() or
vhost_scsi_clear_endpoint() under the vs->dev.mutex lock. However, when
we check it in vhost_scsi_handle_vq(), we ignored the lock.
Instead of using the vs->vs_endpoint and the vs->dev.mutex lock to
indicate the status of the endpoint, we use per virtqueue
vq->private_data to indicate it. In this way, we can only take the
vq->mutex lock which is per queue and make the concurrent multiqueue
process having less lock contention. Further, in the read side of
vq->private_data, we can even do not take the lock if it is accessed in
the vhost worker thread, because it is protected by "vhost rcu".
(nab: Do s/VHOST_FEATURES/~VHOST_SCSI_FEATURES)
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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In vhost_scsi_handle_vq:
tv_tpg = vs->vs_tpg[target];
if (!tv_tpg) {
....
return
}
tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,
1) vs->vs_tpg[target] might change after the NULL check and 2) the above
line might access tv_tpg from vs->vs_tpg[target]. To prevent 2), use
ACCESS_ONCE. Thanks mst for catching this up!
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is a set of ten bug fixes (and two consisting of copyright year
update and version number change) pretty much all of which involve
either a crash or a hang except the removal of the random sleep from
the qla2xxx driver (which is a coding error so bad, we want it gone
before anyone has a chance to copy it)."
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
[SCSI] lpfc: fix potential NULL pointer dereference in lpfc_sli4_rq_put()
[SCSI] libsas: fix handling vacant phy in sas_set_ex_phy()
[SCSI] ibmvscsi: Fix slave_configure deadlock
[SCSI] qla2xxx: Update the driver version to 8.04.00.13-k.
[SCSI] qla2xxx: Remove debug code that msleeps for random duration.
[SCSI] qla2xxx: Update copyright dates information in LICENSE.qla2xxx file.
[SCSI] qla2xxx: Fix crash during firmware dump procedure.
[SCSI] Revert "qla2xxx: Add setting of driver version string for vendor application."
[SCSI] ipr: dlpar failed when adding an adapter back
[SCSI] ipr: fix addition of abort command to HRRQ free queue
[SCSI] st: Take additional queue ref in st_probe
[SCSI] libsas: use right function to alloc smp response
[SCSI] ipr: ipr_test_msi() fails when running with msi-x enabled adapter
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The dereference to 'put_index' should be moved below the NULL test.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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If a result of the SMP discover function is PHY VACANT,
the content of discover response structure (dr) is not valid.
It sometimes happens that dr->attached_sas_addr can contain
even SAS address of other phy. In such case an invalid phy
is created, what causes NULL pointer dereference during
destruction of expander's phys.
So if a result of SMP function is PHY VACANT, the content of discover
response structure (dr) must not be copied to phy structure.
This patch fixes the following bug:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffff811c9002>] sysfs_find_dirent+0x12/0x90
Call Trace:
[<ffffffff811c95f5>] sysfs_get_dirent+0x35/0x80
[<ffffffff811cb55e>] sysfs_unmerge_group+0x1e/0xb0
[<ffffffff813329f4>] dpm_sysfs_remove+0x24/0x90
[<ffffffff8132b0f4>] device_del+0x44/0x1d0
[<ffffffffa016fc59>] sas_rphy_delete+0x9/0x20 [scsi_transport_sas]
[<ffffffffa01a16f6>] sas_destruct_devices+0xe6/0x110 [libsas]
[<ffffffff8107ac7c>] process_one_work+0x16c/0x350
[<ffffffff8107d84a>] worker_thread+0x17a/0x410
[<ffffffff81081b76>] kthread+0x96/0xa0
[<ffffffff81464944>] kernel_thread_helper+0x4/0x10
Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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No locks should be held when calling scsi_adjust_queue_depth
so drop the lock in slave_configure prior to calling it.
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Acked-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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System crashes, in initiator mode operation, with
qla2xxx_copy_atioqueues() in stack trace when firmware dump is
attempted.
Check for atio_q_length alone does not indicate if atio_ring is
allocated, make explicit check of atio_ring to avoid the crash.
Applicable to ISP24xx, ISP25xx, ISP81xx & ISP83xx line of HBAs.
Signed-off-by: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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application."
The original patch was not covering all the adapters and firmwares.
This commit reverts 3a11711ad00caebee07e262d188cea66f3473c38.
Signed-off-by: Joe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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Reinitialize resource queue prior to freeing resource entries to ensure they
are not referenced. This fixes an issue with target_destoy accessing memory
after it was freed.
Signed-off-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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The abort command issued by ipr_cancel_op() is being added to the wrong
HRRQ free queue after the command returns. Fix it by using the HRRQ
pointer in the ipr command struct itself.
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Signed-off-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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This patch fixes a reference count bug in the SCSI tape driver which can be
reproduced with the following:
* Boot with slub_debug=FZPU, tape drive attached
* echo 1 > /sys/devices/... tape device pci path .../remove
* Wait for device removal
* echo 1 > /sys/kernel/slab/blkdev_queue/validate
* Slub debug complains about corrupted poison pattern
In commit 523e1d39 (block: make gendisk hold a reference to its queue)
add_disk() and disk_release() were modified to get/put an additional
reference on a disk queue to fix a reference counting discrepency
between bdev release and SCSI device removal. The ST driver never
calls add_disk(), so this commit introduced an extra kref put when the
ST driver frees its struct gendisk.
Attempts were made to fix this bug at the block level [1] but later
abandoned due to floppy driver issues [2].
[1] https://lkml.org/lkml/2012/8/27/354
[2] https://lkml.org/lkml/2012/9/22/113
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Tested-by: Ewan D. Milne <emilne@redhat.com>
Acked-by: Kai Mäkisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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In fact the disc_resp buffer will be overwrite by smp response, so we never
found this typo, correct it by using the right one.
Signed-off-by: John Gong <john_gong@usish.com>
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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