| Commit message (Collapse) | Author | Age | Files | Lines |
|---|
| |\
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| | |
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
"A single fix for POSIX CPU timers to address a problem where POSIX CPU
timer delivery stops working for a new child task because
copy_process() copies state information which is only valid for the
parent task"
* tag 'timers-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()
|
| | |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| | |
copy_process currently copies task_struct.posix_cputimers_work as-is. If a
timer interrupt arrives while handling clone and before dup_task_struct
completes then the child task will have:
1. posix_cputimers_work.scheduled = true
2. posix_cputimers_work.work queued.
copy_process clears task_struct.task_works, so (2) will have no effect and
posix_cpu_timers_work will never run (not to mention it doesn't make sense
for two tasks to share a common linked list).
Since posix_cpu_timers_work never runs, posix_cputimers_work.scheduled is
never cleared. Since scheduled is set, future timer interrupts will skip
scheduling work, with the ultimate result that the task will never receive
timer expirations.
Together, the complete flow is:
1. Task 1 calls clone(), enters kernel.
2. Timer interrupt fires, schedules task work on Task 1.
2a. task_struct.posix_cputimers_work.scheduled = true
2b. task_struct.posix_cputimers_work.work added to
task_struct.task_works.
3. dup_task_struct() copies Task 1 to Task 2.
4. copy_process() clears task_struct.task_works for Task 2.
5. Future timer interrupts on Task 2 see
task_struct.posix_cputimers_work.scheduled = true and skip scheduling
work.
Fix this by explicitly clearing contents of task_struct.posix_cputimers_work
in copy_process(). This was never meant to be shared or inherited across
tasks in the first place.
Fixes: 1fb497dd0030 ("posix-cpu-timers: Provide mechanisms to defer timer handling to task_work")
Reported-by: Rhys Hiltner <rhys@justin.tv>
Signed-off-by: Michael Pratt <mpratt@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211101210615.716522-1-mpratt@google.com
|
| |\ \
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | | |
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"A set of fixes for the interrupt subsystem
Core code:
- A regression fix for the Open Firmware interrupt mapping code where
a interrupt controller property in a node caused a map property in
the same node to be ignored.
Interrupt chip drivers:
- Workaround a limitation in SiFive PLIC interrupt chip which
silently ignores an EOI when the interrupt line is masked.
- Provide the missing mask/unmask implementation for the CSKY MP
interrupt controller.
PCI/MSI:
- Prevent a use after free when PCI/MSI interrupts are released by
destroying the sysfs entries before freeing the memory which is
accessed in the sysfs show() function.
- Implement a mask quirk for the Nvidia ION AHCI chip which does not
advertise masking capability despite implementing it. Even worse
the chip comes out of reset with all MSI entries masked, which due
to the missing masking capability never get unmasked.
- Move the check which prevents accessing the MSI[X] masking for XEN
back into the low level accessors. The recent consolidation missed
that these accessors can be invoked from places which do not have
that check which broke XEN. Move them back to he original place
instead of sprinkling tons of these checks all over the code"
* tag 'irq-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
of/irq: Don't ignore interrupt-controller when interrupt-map failed
irqchip/sifive-plic: Fixup EOI failed when masked
irqchip/csky-mpintc: Fixup mask/unmask implementation
PCI/MSI: Destroy sysfs before freeing entries
PCI: Add MSI masking quirk for Nvidia ION AHCI
PCI/MSI: Deal with devices lying about their MSI mask capability
PCI/MSI: Move non-mask check back into low level accessors
|
| | | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | | |
The recent rework of PCI/MSI[X] masking moved the non-mask checks from the
low level accessors into the higher level mask/unmask functions.
This missed the fact that these accessors can be invoked from other places
as well. The missing checks break XEN-PV which sets pci_msi_ignore_mask and
also violates the virtual MSIX and the msi_attrib.maskbit protections.
Instead of sprinkling checks all over the place, lift them back into the
low level accessor functions. To avoid checking three different conditions
combine them into one property of msi_desc::msi_attrib.
[ josef: Fixed the missed conversion in the core code ]
Fixes: fcacdfbef5a1 ("PCI/MSI: Provide a new set of mask and unmask functions")
Reported-by: Josef Johansson <josef@oderland.se>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Josef Johansson <josef@oderland.se>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: stable@vger.kernel.org
|
| |\ \ \
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Borislav Petkov:
- Avoid touching ~100 config files in order to be able to select the
preemption model
- clear cluster CPU masks too, on the CPU unplug path
- prevent use-after-free in cfs
- Prevent a race condition when updating CPU cache domains
- Factor out common shared part of smp_prepare_cpus() into a common
helper which can be called by both baremetal and Xen, in order to fix
a booting of Xen PV guests
* tag 'sched_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
preempt: Restore preemption model selection configs
arch_topology: Fix missing clear cluster_cpumask in remove_cpu_topology()
sched/fair: Prevent dead task groups from regaining cfs_rq's
sched/core: Mitigate race cpus_share_cache()/update_top_cache_domain()
x86/smp: Factor out parts of native_smp_prepare_cpus()
|
| | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
Commit c597bfddc9e9 ("sched: Provide Kconfig support for default dynamic
preempt mode") changed the selectable config names for the preemption
model. This means a config file must now select
CONFIG_PREEMPT_BEHAVIOUR=y
rather than
CONFIG_PREEMPT=y
to get a preemptible kernel. This means all arch config files would need to
be updated - right now they'll all end up with the default
CONFIG_PREEMPT_NONE_BEHAVIOUR.
Rather than touch a good hundred of config files, restore usage of
CONFIG_PREEMPT{_NONE, _VOLUNTARY}. Make them configure:
o The build-time preemption model when !PREEMPT_DYNAMIC
o The default boot-time preemption model when PREEMPT_DYNAMIC
Add siblings of those configs with the _BUILD suffix to unconditionally
designate the build-time preemption model (PREEMPT_DYNAMIC is built with
the "highest" preemption model it supports, aka PREEMPT). Downstream
configs should by now all be depending / selected by CONFIG_PREEMPTION
rather than CONFIG_PREEMPT, so only a few sites need patching up.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20211110202448.4054153-2-valentin.schneider@arm.com
|
| | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
Kevin is reporting crashes which point to a use-after-free of a cfs_rq
in update_blocked_averages(). Initial debugging revealed that we've
live cfs_rq's (on_list=1) in an about to be kfree()'d task group in
free_fair_sched_group(). However, it was unclear how that can happen.
His kernel config happened to lead to a layout of struct sched_entity
that put the 'my_q' member directly into the middle of the object
which makes it incidentally overlap with SLUB's freelist pointer.
That, in combination with SLAB_FREELIST_HARDENED's freelist pointer
mangling, leads to a reliable access violation in form of a #GP which
made the UAF fail fast.
Michal seems to have run into the same issue[1]. He already correctly
diagnosed that commit a7b359fc6a37 ("sched/fair: Correctly insert
cfs_rq's to list on unthrottle") is causing the preconditions for the
UAF to happen by re-adding cfs_rq's also to task groups that have no
more running tasks, i.e. also to dead ones. His analysis, however,
misses the real root cause and it cannot be seen from the crash
backtrace only, as the real offender is tg_unthrottle_up() getting
called via sched_cfs_period_timer() via the timer interrupt at an
inconvenient time.
When unregister_fair_sched_group() unlinks all cfs_rq's from the dying
task group, it doesn't protect itself from getting interrupted. If the
timer interrupt triggers while we iterate over all CPUs or after
unregister_fair_sched_group() has finished but prior to unlinking the
task group, sched_cfs_period_timer() will execute and walk the list of
task groups, trying to unthrottle cfs_rq's, i.e. re-add them to the
dying task group. These will later -- in free_fair_sched_group() -- be
kfree()'ed while still being linked, leading to the fireworks Kevin
and Michal are seeing.
To fix this race, ensure the dying task group gets unlinked first.
However, simply switching the order of unregistering and unlinking the
task group isn't sufficient, as concurrent RCU walkers might still see
it, as can be seen below:
CPU1: CPU2:
: timer IRQ:
: do_sched_cfs_period_timer():
: :
: distribute_cfs_runtime():
: rcu_read_lock();
: :
: unthrottle_cfs_rq():
sched_offline_group(): :
: walk_tg_tree_from(…,tg_unthrottle_up,…):
list_del_rcu(&tg->list); :
(1) : list_for_each_entry_rcu(child, &parent->children, siblings)
: :
(2) list_del_rcu(&tg->siblings); :
: tg_unthrottle_up():
unregister_fair_sched_group(): struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
: :
list_del_leaf_cfs_rq(tg->cfs_rq[cpu]); :
: :
: if (!cfs_rq_is_decayed(cfs_rq) || cfs_rq->nr_running)
(3) : list_add_leaf_cfs_rq(cfs_rq);
: :
: :
: :
: :
: :
(4) : rcu_read_unlock();
CPU 2 walks the task group list in parallel to sched_offline_group(),
specifically, it'll read the soon to be unlinked task group entry at
(1). Unlinking it on CPU 1 at (2) therefore won't prevent CPU 2 from
still passing it on to tg_unthrottle_up(). CPU 1 now tries to unlink
all cfs_rq's via list_del_leaf_cfs_rq() in
unregister_fair_sched_group(). Meanwhile CPU 2 will re-add some of
these at (3), which is the cause of the UAF later on.
To prevent this additional race from happening, we need to wait until
walk_tg_tree_from() has finished traversing the task groups, i.e.
after the RCU read critical section ends in (4). Afterwards we're safe
to call unregister_fair_sched_group(), as each new walk won't see the
dying task group any more.
On top of that, we need to wait yet another RCU grace period after
unregister_fair_sched_group() to ensure print_cfs_stats(), which might
run concurrently, always sees valid objects, i.e. not already free'd
ones.
This patch survives Michal's reproducer[2] for 8h+ now, which used to
trigger within minutes before.
[1] https://lore.kernel.org/lkml/20211011172236.11223-1-mkoutny@suse.com/
[2] https://lore.kernel.org/lkml/20211102160228.GA57072@blackbody.suse.cz/
Fixes: a7b359fc6a37 ("sched/fair: Correctly insert cfs_rq's to list on unthrottle")
[peterz: shuffle code around a bit]
Reported-by: Kevin Tanguy <kevin.tanguy@corp.ovh.com>
Signed-off-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
|
| | |/ /
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | | |
Nothing protects the access to the per_cpu variable sd_llc_id. When testing
the same CPU (i.e. this_cpu == that_cpu), a race condition exists with
update_top_cache_domain(). One scenario being:
CPU1 CPU2
==================================================================
per_cpu(sd_llc_id, CPUX) => 0
partition_sched_domains_locked()
detach_destroy_domains()
cpus_share_cache(CPUX, CPUX) update_top_cache_domain(CPUX)
per_cpu(sd_llc_id, CPUX) => 0
per_cpu(sd_llc_id, CPUX) = CPUX
per_cpu(sd_llc_id, CPUX) => CPUX
return false
ttwu_queue_cond() wouldn't catch smp_processor_id() == cpu and the result
is a warning triggered from ttwu_queue_wakelist().
Avoid a such race in cpus_share_cache() by always returning true when
this_cpu == that_cpu.
Fixes: 518cd6234178 ("sched: Only queue remote wakeups when crossing cache boundaries")
Reported-by: Jing-Ting Wu <jing-ting.wu@mediatek.com>
Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20211104175120.857087-1-vincent.donnefort@arm.com
|
| |\ \ \
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Prevent unintentional page sharing by checking whether a page
reference to a PMU samples page has been acquired properly before
that
- Make sure the LBR_SELECT MSR is saved/restored too
- Reset the LBR_SELECT MSR when resetting the LBR PMU to clear any
residual data left
* tag 'perf_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Avoid put_page() when GUP fails
perf/x86/vlbr: Add c->flags to vlbr event constraints
perf/x86/lbr: Reset LBR_SELECT during vlbr reset
|
| | |/ /
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | | |
PEBS PERF_SAMPLE_PHYS_ADDR events use perf_virt_to_phys() to convert PMU
sampled virtual addresses to physical using get_user_page_fast_only()
and page_to_phys().
Some get_user_page_fast_only() error cases return false, indicating no
page reference, but still initialize the output page pointer with an
unreferenced page. In these error cases perf_virt_to_phys() calls
put_page(). This causes page reference count underflow, which can lead
to unintentional page sharing.
Fix perf_virt_to_phys() to only put_page() if get_user_page_fast_only()
returns a referenced page.
Fixes: fc7ce9c74c3ad ("perf/core, x86: Add PERF_SAMPLE_PHYS_ADDR")
Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211111021814.757086-1-gthelen@google.com
|
| |\ \ \
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Three tracing fixes:
- Make local osnoise_instances static
- Copy just actual size of histogram strings
- Properly check missing operands in histogram expressions"
* tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/histogram: Fix check for missing operands in an expression
tracing/histogram: Do not copy the fixed-size char array field over the field size
tracing/osnoise: Make osnoise_instances static
|
| | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
If a binary operation is detected while parsing an expression string,
the operand strings are deduced by splitting the experssion string at
the position of the detected binary operator. Both operand strings are
sub-strings (can be empty string) of the expression string but will
never be NULL.
Currently a NULL check is used for missing operands, fix this by
checking for empty strings instead.
Link: https://lkml.kernel.org/r/20211112191324.1302505-1-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Fixes: 9710b2f341a0 ("tracing: Fix operator precedence for hist triggers expression")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
| | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
field size
Do not copy the fixed-size char array field of the events over
the field size. The histogram treats char array as a string and
there are 2 types of char array in the event, fixed-size and
dynamic string. The dynamic string (__data_loc) field must be
null terminated, but the fixed-size char array field may not
be null terminated (not a string, but just a data).
In that case, histogram can copy the data after the field.
This uses the original field size for fixed-size char array
field to restrict the histogram not to access over the original
field size.
Link: https://lkml.kernel.org/r/163673292822.195747.3696966210526410250.stgit@devnote2
Fixes: 02205a6752f2 (tracing: Add support for 'field variables')
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
| | | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | | |
Make the struct list_head osnoise_instances definition static.
Link: https://lore.kernel.org/all/202111120052.ZuikQSJi-lkp@intel.com/
Link: https://lkml.kernel.org/r/d001f0eeac66e2b2eeec7d2a15e9e7abede0453a.1636667971.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
| |\ \ \ \
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
"Just one new driver (Cypress StreetFighter touchkey), and no input
core changes this time.
Plus various fixes and enhancements to existing drivers"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (54 commits)
Input: iforce - fix control-message timeout
Input: wacom_i2c - use macros for the bit masks
Input: ili210x - reduce sample period to 15ms
Input: ili210x - improve polled sample spacing
Input: ili210x - special case ili251x sample read out
Input: elantench - fix misreporting trackpoint coordinates
Input: synaptics-rmi4 - Fix device hierarchy
Input: i8042 - Add quirk for Fujitsu Lifebook T725
Input: cap11xx - add support for cap1206
Input: remove unused header <linux/input/cy8ctmg110_pdata.h>
Input: ili210x - add ili251x firmware update support
Input: ili210x - export ili251x version details via sysfs
Input: ili210x - use resolution from ili251x firmware
Input: pm8941-pwrkey - respect reboot_mode for warm reset
reboot: export symbol 'reboot_mode'
Input: max77693-haptic - drop unneeded MODULE_ALIAS
Input: cpcap-pwrbutton - do not set input parent explicitly
Input: max8925_onkey - don't mark comment as kernel-doc
Input: ads7846 - do not attempt IRQ workaround when deferring probe
Input: ads7846 - use input_set_capability()
...
|
| | | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | |
| | | | | |
Some drivers like Qualcomm pm8941-pwrkey need to access 'reboot_mode'
for triggering reboot between cold and warm mode. Export the symbol, so
that drivers built as module can still access the symbol.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20210714095850.27185-2-shawn.guo@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
|
| |\ \ \ \ \
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull KCSAN updates from Paul McKenney:
"This contains initialization fixups, testing improvements, addition of
instruction pointer to data-race reports, and scoped data-race checks"
* tag 'kcsan.2021.11.11a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
kcsan: selftest: Cleanup and add missing __init
kcsan: Move ctx to start of argument list
kcsan: Support reporting scoped read-write access type
kcsan: Start stack trace with explicit location if provided
kcsan: Save instruction pointer for scoped accesses
kcsan: Add ability to pass instruction pointer of access to reporting
kcsan: test: Fix flaky test case
kcsan: test: Use kunit_skip() to skip tests
kcsan: test: Defer kcsan_test_init() after kunit initialization
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
Make test_encode_decode() more readable and add missing __init.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
It is clearer if ctx is at the start of the function argument list;
it'll be more consistent when adding functions with varying arguments
but all requiring ctx.
No functional change intended.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
Support generating the string representation of scoped read-write
accesses for completeness. They will become required in planned changes.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
If an explicit access address is set, as is done for scoped accesses,
always start the stack trace from that location. get_stack_skipnr() is
changed into sanitize_stack_entries(), which if given an address, scans
the stack trace for a matching function and then replaces that entry
with the explicitly provided address.
The previous reports for scoped accesses were all over the place, which
could be quite confusing. We now always point at the start of the scope.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
Save the instruction pointer for scoped accesses, so that it becomes
possible for the reporting code to construct more accurate stack traces
that will show the start of the scope.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
Add the ability to pass an explicitly set instruction pointer of access
from check_access() all the way through to reporting.
In preparation of using it in reporting.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
If CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY=n, then we may also see data
races between the writers only. If we get unlucky and never capture a
read-write data race, but only the write-write data races, then the
test_no_value_change* test cases may incorrectly fail.
The second problem is that the initial value needs to be reset, as
otherwise we might actually observe a value change at the start.
Fix it by also looking for the write-write data races, and resetting the
value to what will be written.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
Use the new kunit_skip() to skip tests if requirements were not met.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
When the test is built into the kernel (not a module), kcsan_test_init()
and kunit_init() both use late_initcall(), which means kcsan_test_init()
might see a NULL debugfs_rootdir as parent dentry, resulting in
kcsan_test_init() and kcsan_debugfs_init() both trying to create a
debugfs node named "kcsan" in debugfs root. One of them will show an
error and be unsuccessful.
Defer kcsan_test_init() until we're sure kunit was initialized.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
|
| |\ \ \ \ \ \
| | |_|/ / /
| |/| | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two locking fixes:
- Add mutex protection to ring_buffer_reset()
- Fix deadlock in modify_ftrace_direct_multi()"
* tag 'trace-v5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/direct: Fix lockup in modify_ftrace_direct_multi
ring-buffer: Protect ring_buffer_reset() from reentrancy
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
We can't call unregister_ftrace_function under ftrace_lock.
Link: https://lkml.kernel.org/r/20211109114217.1645296-1-jolsa@kernel.org
Fixes: ed29271894aa ("ftrace/direct: Do not disable when switching direct callers")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
The resetting of the entire ring buffer use to simply go through and reset
each individual CPU buffer that had its own protection and synchronization.
But this was very slow, due to performing a synchronization for each CPU.
The code was reshuffled to do one disabling of all CPU buffers, followed
by a single RCU synchronization, and then the resetting of each of the CPU
buffers. But unfortunately, the mutex that prevented multiple occurrences
of resetting the buffer was not moved to the upper function, and there is
nothing to protect from it.
Take the ring buffer mutex around the global reset.
Cc: stable@vger.kernel.org
Fixes: b23d7a5f4a07a ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU")
Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
| |\ \ \ \ \ \
| |_|_|_|/ /
|/| | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, can and netfilter.
Current release - regressions:
- bpf: do not reject when the stack read size is different from the
tracked scalar size
- net: fix premature exit from NAPI state polling in napi_disable()
- riscv, bpf: fix RV32 broken build, and silence RV64 warning
Current release - new code bugs:
- net: fix possible NULL deref in sock_reserve_memory
- amt: fix error return code in amt_init(); fix stopping the
workqueue
- ax88796c: use the correct ioctl callback
Previous releases - always broken:
- bpf: stop caching subprog index in the bpf_pseudo_func insn
- security: fixups for the security hooks in sctp
- nfc: add necessary privilege flags in netlink layer, limit
operations to admin only
- vsock: prevent unnecessary refcnt inc for non-blocking connect
- net/smc: fix sk_refcnt underflow on link down and fallback
- nfnetlink_queue: fix OOB when mac header was cleared
- can: j1939: ignore invalid messages per standard
- bpf, sockmap:
- fix race in ingress receive verdict with redirect to self
- fix incorrect sk_skb data_end access when src_reg = dst_reg
- strparser, and tls are reusing qdisc_skb_cb and colliding
- ethtool: fix ethtool msg len calculation for pause stats
- vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries to
access an unregistering real_dev
- udp6: make encap_rcv() bump the v6 not v4 stats
- drv: prestera: add explicit padding to fix m68k build
- drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge
- drv: mvpp2: fix wrong SerDes reconfiguration order
Misc & small latecomers:
- ipvs: auto-load ipvs on genl access
- mctp: sanity check the struct sockaddr_mctp padding fields
- libfs: support RENAME_EXCHANGE in simple_rename()
- avoid double accounting for pure zerocopy skbs"
* tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (123 commits)
selftests/net: udpgso_bench_rx: fix port argument
net: wwan: iosm: fix compilation warning
cxgb4: fix eeprom len when diagnostics not implemented
net: fix premature exit from NAPI state polling in napi_disable()
net/smc: fix sk_refcnt underflow on linkdown and fallback
net/mlx5: Lag, fix a potential Oops with mlx5_lag_create_definer()
gve: fix unmatched u64_stats_update_end()
net: ethernet: lantiq_etop: Fix compilation error
selftests: forwarding: Fix packet matching in mirroring selftests
vsock: prevent unnecessary refcnt inc for nonblocking connect
net: marvell: mvpp2: Fix wrong SerDes reconfiguration order
net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory
net: stmmac: allow a tc-taprio base-time of zero
selftests: net: test_vxlan_under_vrf: fix HV connectivity test
net: hns3: allow configure ETS bandwidth of all TCs
net: hns3: remove check VF uc mac exist when set by PF
net: hns3: fix some mac statistics is always 0 in device version V2
net: hns3: fix kernel crash when unload VF while it is being reset
net: hns3: sync rx ring head in echo common pull
net: hns3: fix pfc packet number incorrect after querying pfc parameters
...
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
This patch is to fix an out-of-bound access issue when jit-ing the
bpf_pseudo_func insn (i.e. ld_imm64 with src_reg == BPF_PSEUDO_FUNC)
In jit_subprog(), it currently reuses the subprog index cached in
insn[1].imm. This subprog index is an index into a few array related
to subprogs. For example, in jit_subprog(), it is an index to the newly
allocated 'struct bpf_prog **func' array.
The subprog index was cached in insn[1].imm after add_subprog(). However,
this could become outdated (and too big in this case) if some subprogs
are completely removed during dead code elimination (in
adjust_subprog_starts_after_remove). The cached index in insn[1].imm
is not updated accordingly and causing out-of-bound issue in the later
jit_subprog().
Unlike bpf_pseudo_'func' insn, the current bpf_pseudo_'call' insn
is handling the DCE properly by calling find_subprog(insn->imm) to
figure out the index instead of caching the subprog index.
The existing bpf_adj_branches() will adjust the insn->imm
whenever insn is added or removed.
Instead of having two ways handling subprog index,
this patch is to make bpf_pseudo_func works more like
bpf_pseudo_call.
First change is to stop caching the subprog index result
in insn[1].imm after add_subprog(). The verification
process will use find_subprog(insn->imm) to figure
out the subprog index.
Second change is in bpf_adj_branches() and have it to
adjust the insn->imm for the bpf_pseudo_func insn also
whenever insn is added or removed.
Third change is in jit_subprog(). Like the bpf_pseudo_call handling,
bpf_pseudo_func temporarily stores the find_subprog() result
in insn->off. It is fine because the prog's insn has been finalized
at this point. insn->off will be reset back to 0 later to avoid
confusing the userspace prog dump tool.
Fixes: 69c087ba6225 ("bpf: Add bpf_for_each_map_elem() helper")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211106014014.651018-1-kafai@fb.com
|
| | | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | | |
scalar size
Below is a simplified case from a report in bcc [0]:
r4 = 20
*(u32 *)(r10 -4) = r4
*(u32 *)(r10 -8) = r4 /* r4 state is tracked */
r4 = *(u64 *)(r10 -8) /* Read more than the tracked 32bit scalar.
* verifier rejects as 'corrupted spill memory'.
*/
After commit 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill"),
the 8-byte aligned 32bit spill is also tracked by the verifier and the
register state is stored.
However, if 8 bytes are read from the stack instead of the tracked 4 byte
scalar, then verifier currently rejects the program as "corrupted spill
memory". This patch fixes this case by allowing it to read but marks the
register as unknown.
Also note that, if the prog is trying to corrupt/leak an earlier spilled
pointer by spilling another <8 bytes register on top, this has already
been rejected in the check_stack_write_fixed_off().
[0] https://github.com/iovisor/bcc/pull/3683
Fixes: 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill")
Reported-by: Hengqi Chen <hengqi.chen@gmail.com>
Reported-by: Yonghong Song <yhs@gmail.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211102064535.316018-1-kafai@fb.com
|
| |\ \ \ \ \ \
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull exit cleanups from Eric Biederman:
"While looking at some issues related to the exit path in the kernel I
found several instances where the code is not using the existing
abstractions properly.
This set of changes introduces force_fatal_sig a way of sending a
signal and not allowing it to be caught, and corrects the misuse of
the existing abstractions that I found.
A lot of the misuse of the existing abstractions are silly things such
as doing something after calling a no return function, rolling BUG by
hand, doing more work than necessary to terminate a kernel thread, or
calling do_exit(SIGKILL) instead of calling force_sig(SIGKILL).
In the review a deficiency in force_fatal_sig and force_sig_seccomp
where ptrace or sigaction could prevent the delivery of the signal was
found. I have added a change that adds SA_IMMUTABLE to change that
makes it impossible to interrupt the delivery of those signals, and
allows backporting to fix force_sig_seccomp
And Arnd found an issue where a function passed to kthread_run had the
wrong prototype, and after my cleanup was failing to build."
* 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits)
soc: ti: fix wkup_m3_rproc_boot_thread return type
signal: Add SA_IMMUTABLE to ensure forced siganls do not get changed
signal: Replace force_sigsegv(SIGSEGV) with force_fatal_sig(SIGSEGV)
exit/r8188eu: Replace the macro thread_exit with a simple return 0
exit/rtl8712: Replace the macro thread_exit with a simple return 0
exit/rtl8723bs: Replace the macro thread_exit with a simple return 0
signal/x86: In emulate_vsyscall force a signal instead of calling do_exit
signal/sparc32: In setup_rt_frame and setup_fram use force_fatal_sig
signal/sparc32: Exit with a fatal signal when try_to_clear_window_buffer fails
exit/syscall_user_dispatch: Send ordinary signals on failure
signal: Implement force_fatal_sig
exit/kthread: Have kernel threads return instead of calling do_exit
signal/s390: Use force_sigsegv in default_trap_handler
signal/vm86_32: Properly send SIGSEGV when the vm86 state cannot be saved.
signal/vm86_32: Replace open coded BUG_ON with an actual BUG_ON
signal/sparc: In setup_tsb_params convert open coded BUG into BUG
signal/powerpc: On swapcontext failure force SIGSEGV
signal/sh: Use force_sig(SIGKILL) instead of do_group_exit(SIGKILL)
signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT
signal/sparc32: Remove unreachable do_exit in do_sparc_fault
...
|
| | | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
As Andy pointed out that there are races between
force_sig_info_to_task and sigaction[1] when force_sig_info_task. As
Kees discovered[2] ptrace is also able to change these signals.
In the case of seeccomp killing a process with a signal it is a
security violation to allow the signal to be caught or manipulated.
Solve this problem by introducing a new flag SA_IMMUTABLE that
prevents sigaction and ptrace from modifying these forced signals.
This flag is carefully made kernel internal so that no new ABI is
introduced.
Longer term I think this can be solved by guaranteeing short circuit
delivery of signals in this case. Unfortunately reliable and
guaranteed short circuit delivery of these signals is still a ways off
from being implemented, tested, and merged. So I have implemented a much
simpler alternative for now.
[1] https://lkml.kernel.org/r/b5d52d25-7bde-4030-a7b1-7c6f8ab90660@www.fastmail.com
[2] https://lkml.kernel.org/r/202110281136.5CE65399A7@keescook
Cc: stable@vger.kernel.org
Fixes: 307d522f5eb8 ("signal/seccomp: Refactor seccomp signal and coredump generation")
Tested-by: Andrea Righi <andrea.righi@canonical.com>
Tested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
|
| | | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
Use force_fatal_sig instead of calling do_exit directly. This ensures
the ordinary signal handling path gets invoked, core dumps as
appropriate get created, and for multi-threaded processes all of the
threads are terminated not just a single thread.
When asked Gabriel Krisman Bertazi <krisman@collabora.com> said [1]:
> ebiederm@xmission.com (Eric W. Biederman) asked:
>
> > Why does do_syscal_user_dispatch call do_exit(SIGSEGV) and
> > do_exit(SIGSYS) instead of force_sig(SIGSEGV) and force_sig(SIGSYS)?
> >
> > Looking at the code these cases are not expected to happen, so I would
> > be surprised if userspace depends on any particular behaviour on the
> > failure path so I think we can change this.
>
> Hi Eric,
>
> There is not really a good reason, and the use case that originated the
> feature doesn't rely on it.
>
> Unless I'm missing yet another problem and others correct me, I think
> it makes sense to change it as you described.
>
> > Is using do_exit in this way something you copied from seccomp?
>
> I'm not sure, its been a while, but I think it might be just that. The
> first prototype of SUD was implemented as a seccomp mode.
If at some point it becomes interesting we could relax
"force_fatal_sig(SIGSEGV)" to instead say
"force_sig_fault(SIGSEGV, SEGV_MAPERR, sd->selector)".
I avoid doing that in this patch to avoid making it possible
to catch currently uncatchable signals.
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
[1] https://lkml.kernel.org/r/87mtr6gdvi.fsf@collabora.com
Link: https://lkml.kernel.org/r/20211020174406.17889-14-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
| | | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
Add a simple helper force_fatal_sig that causes a signal to be
delivered to a process as if the signal handler was set to SIG_DFL.
Reimplement force_sigsegv based upon this new helper. This fixes
force_sigsegv so that when it forces the default signal handler
to be used the code now forces the signal to be unblocked as well.
Reusing the tested logic in force_sig_info_to_task that was built for
force_sig_seccomp this makes the implementation trivial.
This is interesting both because it makes force_sigsegv simpler and
because there are a couple of buggy places in the kernel that call
do_exit(SIGILL) or do_exit(SIGSYS) because there is no straight
forward way today for those places to simply force the exit of a
process with the chosen signal. Creating force_fatal_sig allows
those places to be implemented with normal signal exits.
Link: https://lkml.kernel.org/r/20211020174406.17889-13-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
| | | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
In 2009 Oleg reworked[1] the kernel threads so that it is not
necessary to call do_exit if you are not using kthread_stop(). Remove
the explicit calls of do_exit and complete_and_exit (with a NULL
completion) that were previously necessary.
[1] 63706172f332 ("kthreads: rework kthread_stop()")
Link: https://lkml.kernel.org/r/20211020174406.17889-12-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
| | | |_|/ / /
| |/| | | |
| | | | | |
| | | | | |
| | | | | | |
Link: https://lkml.kernel.org/r/20211020174406.17889-3-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
| |\ \ \ \ \ \
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull prctl updates from Christian Brauner:
"This contains the missing prctl uapi pieces for PR_SCHED_CORE.
In order to activate core scheduling the caller is expected to specify
the scope of the new core scheduling domain.
For example, passing 2 in the 4th argument of
prctl(PR_SCHED_CORE, PR_SCHED_CORE_CREATE, <pid>, 2, 0);
would indicate that the new core scheduling domain encompasses all
tasks in the process group of <pid>. Specifying 0 would only create a
core scheduling domain for the thread identified by <pid> and 2 would
encompass the whole thread-group of <pid>.
Note, the values 0, 1, and 2 correspond to PIDTYPE_PID, PIDTYPE_TGID,
and PIDTYPE_PGID. A first version tried to expose those values
directly to which I objected because:
- PIDTYPE_* is an enum that is kernel internal which we should not
expose to userspace directly.
- PIDTYPE_* indicates what a given struct pid is used for it doesn't
express a scope.
But what the 4th argument of PR_SCHED_CORE prctl() expresses is the
scope of the operation, i.e. the scope of the core scheduling domain
at creation time. So Eugene's patch now simply introduces three new
defines PR_SCHED_CORE_SCOPE_THREAD, PR_SCHED_CORE_SCOPE_THREAD_GROUP,
and PR_SCHED_CORE_SCOPE_PROCESS_GROUP. They simply express what
happens.
This has been on the mailing list for quite a while with all relevant
scheduler folks Cced. I announced multiple times that I'd pick this up
if I don't see or her anyone else doing it. None of this touches
proper scheduler code but only concerns uapi so I think this is fine.
With core scheduling being quite common now for vm managers (e.g.
moving individual vcpu threads into their own core scheduling domain)
and container managers (e.g. moving the init process into its own core
scheduling domain and letting all created children inherit it) having
to rely on raw numbers passed as the 4th argument in prctl() is a bit
annoying and everyone is starting to come up with their own defines"
* tag 'kernel.sys.v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
uapi/linux/prctl: provide macro definitions for the PR_SCHED_CORE type argument
|
| | | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | | |
Commit 7ac592aa35a684ff ("sched: prctl() core-scheduling interface")
made use of enum pid_type in prctl's arg4; this type and the associated
enumeration definitions are not exposed to userspace. Christian
has suggested to provide additional macro definitions that convey
the meaning of the type argument more in alignment with its actual
usage, and this patch does exactly that.
Link: https://lore.kernel.org/r/20210825170613.GA3884@asgard.redhat.com
Suggested-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Complements: 7ac592aa35a684ff ("sched: prctl() core-scheduling interface")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
|
| |\ \ \ \ \ \ \
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | | |
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd updates from Christian Brauner:
"Various places in the kernel have picked up pidfds.
The two most recent additions have probably been the ability to use
pidfds in bpf maps and the usage of pidfds in mm-based syscalls such
as process_mrelease() and process_madvise().
The same pattern to turn a pidfd into a struct task exists in two
places. One of those places used PIDTYPE_TGID while the other one used
PIDTYPE_PID even though it is clearly documented in all pidfd-helpers
that pidfds __currently__ only refer to thread-group leaders (subject
to change in the future if need be).
This isn't a bug per se but has the potential to be one if we allow
pidfds to refer to individual threads. If that happens we want to
audit all codepaths that make use of them to ensure they can deal with
pidfds refering to individual threads.
This adds a simple helper to turn a pidfd into a struct task making it
easy to grep for such places. Plus, it gets rid of code-duplication"
* tag 'pidfd.v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
mm: use pidfd_get_task()
pid: add pidfd_get_task() helper
|
| | | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | |
| | | | | | | | |
The number of system calls making use of pidfds is constantly
increasing. Some of those new system calls duplicate the code to turn a
pidfd into task_struct it refers to. Give them a simple helper for this.
Link: https://lore.kernel.org/r/20211004125050.1153693-2-christian.brauner@ubuntu.com
Link: https://lore.kernel.org/r/20211011133245.1703103-2-brauner@kernel.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Matthew Bobrowski <repnop@google.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Reviewed-by: Matthew Bobrowski <repnop@google.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
|
| |\ \ \ \ \ \ \ \
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | | |
Pull dma-mapping updates from Christoph Hellwig:
"Just a small set of changes this time. The request dma_direct_alloc
cleanups are still under review and haven't made the cut.
Summary:
- convert sparc32 to the generic dma-direct code
- use bitmap_zalloc (Christophe JAILLET)"
* tag 'dma-mapping-5.16' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: use 'bitmap_zalloc()' when applicable
sparc32: use DMA_DIRECT_REMAP
sparc32: remove dma_make_coherent
sparc32: remove the call to dma_make_coherent in arch_dma_free
|
| | | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | | |
'dma_mem->bitmap' is a bitmap. So use 'bitmap_zalloc()' to simplify code,
improve the semantic and avoid some open-coded arithmetic in allocator
arguments.
Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
consistency.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Christoph Hellwig <hch@lst.de>
|
| |\ \ \ \ \ \ \ \ \
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
Merge more updates from Andrew Morton:
"87 patches.
Subsystems affected by this patch series: mm (pagecache and hugetlb),
procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
sysvfs, kcov, gdb, resource, selftests, and ipc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
selftests/kselftest/runner/run_one(): allow running non-executable files
virtio-mem: disallow mapping virtio-mem memory via /dev/mem
kernel/resource: disallow access to exclusive system RAM regions
kernel/resource: clean up and optimize iomem_is_exclusive()
scripts/gdb: handle split debug for vmlinux
kcov: replace local_irq_save() with a local_lock_t
kcov: avoid enable+disable interrupts if !in_task()
kcov: allocate per-CPU memory on the relevant node
Documentation/kcov: define `ip' in the example
Documentation/kcov: include types.h in the example
sysv: use BUILD_BUG_ON instead of runtime check
kernel/fork.c: unshare(): use swap() to make code cleaner
seq_file: fix passing wrong private data
seq_file: move seq_escape() to a header
signal: remove duplicate include in signal.h
crash_dump: remove duplicate include in crash_dump.h
crash_dump: fix boolreturn.cocci warning
hfs/hfsplus: use WARN_ON for sanity check
...
|
| | | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
virtio-mem dynamically exposes memory inside a device memory region as
system RAM to Linux, coordinating with the hypervisor which parts are
actually "plugged" and consequently usable/accessible.
On the one hand, the virtio-mem driver adds/removes whole memory blocks,
creating/removing busy IORESOURCE_SYSTEM_RAM resources, on the other
hand, it logically (un)plugs memory inside added memory blocks,
dynamically either exposing them to the buddy or hiding them from the
buddy and marking them PG_offline.
In contrast to physical devices, like a DIMM, the virtio-mem driver is
required to actually make use of any of the device-provided memory,
because it performs the handshake with the hypervisor. virtio-mem
memory cannot simply be access via /dev/mem without a driver.
There is no safe way to:
a) Access plugged memory blocks via /dev/mem, as they might contain
unplugged holes or might get silently unplugged by the virtio-mem
driver and consequently turned inaccessible.
b) Access unplugged memory blocks via /dev/mem because the virtio-mem
driver is required to make them actually accessible first.
The virtio-spec states that unplugged memory blocks MUST NOT be written,
and only selected unplugged memory blocks MAY be read. We want to make
sure, this is the case in sane environments -- where the virtio-mem driver
was loaded.
We want to make sure that in a sane environment, nobody "accidentially"
accesses unplugged memory inside the device managed region. For example,
a user might spot a memory region in /proc/iomem and try accessing it via
/dev/mem via gdb or dumping it via something else. By the time the mmap()
happens, the memory might already have been removed by the virtio-mem
driver silently: the mmap() would succeeed and user space might
accidentially access unplugged memory.
So once the driver was loaded and detected the device along the
device-managed region, we just want to disallow any access via /dev/mem to
it.
In an ideal world, we would mark the whole region as busy ("owned by a
driver") and exclude it; however, that would be wrong, as we don't really
have actual system RAM at these ranges added to Linux ("busy system RAM").
Instead, we want to mark such ranges as "not actual busy system RAM but
still soft-reserved and prepared by a driver for future use."
Let's teach iomem_is_exclusive() to reject access to any range with
"IORESOURCE_SYSTEM_RAM | IORESOURCE_EXCLUSIVE", even if not busy and even
if "iomem=relaxed" is set. Introduce EXCLUSIVE_SYSTEM_RAM to make it
easier for applicable drivers to depend on this setting in their Kconfig.
For now, there are no applicable ranges and we'll modify virtio-mem next
to properly set IORESOURCE_EXCLUSIVE on the parent resource container it
creates to contain all actual busy system RAM added via
add_memory_driver_managed().
Link: https://lkml.kernel.org/r/20210920142856.17758-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| | | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
Patch series "virtio-mem: disallow mapping virtio-mem memory via /dev/mem", v5.
Let's add the basic infrastructure to exclude some physical memory regions
marked as "IORESOURCE_SYSTEM_RAM" completely from /dev/mem access, even
though they are not marked IORESOURCE_BUSY and even though "iomem=relaxed"
is set. Resource IORESOURCE_EXCLUSIVE for that purpose instead of adding
new flags to express something similar to "soft-busy" or "not busy yet,
but already prepared by a driver and not to be mapped by user space".
Use it for virtio-mem, to disallow mapping any virtio-mem memory via
/dev/mem to user space after the virtio-mem driver was loaded.
This patch (of 3):
We end up traversing subtrees of ranges we are not interested in; let's
optimize this case, skipping such subtrees, cleaning up the function a
bit.
For example, in the following configuration (/proc/iomem):
00000000-00000fff : Reserved
00001000-00057fff : System RAM
00058000-00058fff : Reserved
00059000-0009cfff : System RAM
0009d000-000fffff : Reserved
000a0000-000bffff : PCI Bus 0000:00
000c0000-000c3fff : PCI Bus 0000:00
000c4000-000c7fff : PCI Bus 0000:00
000c8000-000cbfff : PCI Bus 0000:00
000cc000-000cffff : PCI Bus 0000:00
000d0000-000d3fff : PCI Bus 0000:00
000d4000-000d7fff : PCI Bus 0000:00
000d8000-000dbfff : PCI Bus 0000:00
000dc000-000dffff : PCI Bus 0000:00
000e0000-000e3fff : PCI Bus 0000:00
000e4000-000e7fff : PCI Bus 0000:00
000e8000-000ebfff : PCI Bus 0000:00
000ec000-000effff : PCI Bus 0000:00
000f0000-000fffff : PCI Bus 0000:00
000f0000-000fffff : System ROM
00100000-3fffffff : System RAM
40000000-403fffff : Reserved
40000000-403fffff : pnp 00:00
40400000-80a79fff : System RAM
...
We don't have to look at any children of "0009d000-000fffff : Reserved"
if we can just skip these 15 items directly because the parent range is
not of interest.
Link: https://lkml.kernel.org/r/20210920142856.17758-1-david@redhat.com
Link: https://lkml.kernel.org/r/20210920142856.17758-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| | | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
The kcov code mixes local_irq_save() and spin_lock() in
kcov_remote_{start|end}(). This creates a warning on PREEMPT_RT because
local_irq_save() disables interrupts and spin_lock_t is turned into a
sleeping lock which can not be acquired in a section with disabled
interrupts.
The kcov_remote_lock is used to synchronize the access to the hash-list
kcov_remote_map. The local_irq_save() block protects access to the
per-CPU data kcov_percpu_data.
There is no compelling reason to change the lock type to raw_spin_lock_t
to make it work with local_irq_save(). Changing it would require to
move memory allocation (in kcov_remote_add()) and deallocation outside
of the locked section.
Adding an unlimited amount of entries to the hashlist will increase the
IRQ-off time during lookup. It could be argued that this is debug code
and the latency does not matter. There is however no need to do so and
it would allow to use this facility in an RT enabled build.
Using a local_lock_t instead of local_irq_save() has the befit of adding
a protection scope within the source which makes it obvious what is
protected. On a !PREEMPT_RT && !LOCKDEP build the local_lock_irqsave()
maps directly to local_irq_save() so there is overhead at runtime.
Replace the local_irq_save() section with a local_lock_t.
Link: https://lkml.kernel.org/r/20210923164741.1859522-6-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-6-bigeasy@linutronix.de
Reported-by: Clark Williams <williams@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| | | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
kcov_remote_start() may need to allocate memory in the in_task() case
(otherwise per-CPU memory has been pre-allocated) and therefore requires
enabled interrupts.
The interrupts are enabled before checking if the allocation is required
so if no allocation is required then the interrupts are needlessly enabled
and disabled again.
Enable interrupts only if memory allocation is performed.
Link: https://lkml.kernel.org/r/20210923164741.1859522-5-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-5-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
| | | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | |
| | | | | | | | | | |
During boot kcov allocates per-CPU memory which is used later if remote/
softirq processing is enabled.
Allocate the per-CPU memory on the CPU local node to avoid cross node
memory access.
Link: https://lkml.kernel.org/r/20210923164741.1859522-4-bigeasy@linutronix.de
Link: https://lore.kernel.org/r/20210830172627.267989-4-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Marco Elver <elver@google.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
