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* Merge branch 'android-4.4-p' of ↵Michael Bestas2020-03-08
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | https://android.googlesource.com/kernel/common into lineage-17.1-caf-msm8998 This brings LA.UM.8.4.r1-05200-8x98.0 up to date with https://android.googlesource.com/kernel/common/ android-4.4-p at commit: 4db1ebdd40ec0 FROMLIST: HID: nintendo: add nintendo switch controller driver Conflicts: arch/arm64/boot/Makefile arch/arm64/kernel/psci.c arch/x86/configs/x86_64_cuttlefish_defconfig drivers/md/dm.c drivers/of/Kconfig drivers/thermal/thermal_core.c fs/proc/meminfo.c kernel/locking/spinlock_debug.c kernel/time/hrtimer.c net/wireless/util.c Change-Id: I5b5163497b7c6ab8487ffbb2d036e4cda01ed670
| * locking/spinlock/debug: Fix various data racesMarco Elver2020-01-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 1a365e822372ba24c9da0822bc583894f6f3d821 ] This fixes various data races in spinlock_debug. By testing with KCSAN, it is observable that the console gets spammed with data races reports, suggesting these are extremely frequent. Example data race report: read to 0xffff8ab24f403c48 of 4 bytes by task 221 on cpu 2: debug_spin_lock_before kernel/locking/spinlock_debug.c:85 [inline] do_raw_spin_lock+0x9b/0x210 kernel/locking/spinlock_debug.c:112 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_lock+0x39/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] get_partial_node.isra.0.part.0+0x32/0x2f0 mm/slub.c:1873 get_partial_node mm/slub.c:1870 [inline] <snip> write to 0xffff8ab24f403c48 of 4 bytes by task 167 on cpu 3: debug_spin_unlock kernel/locking/spinlock_debug.c:103 [inline] do_raw_spin_unlock+0xc9/0x1a0 kernel/locking/spinlock_debug.c:138 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:159 [inline] _raw_spin_unlock_irqrestore+0x2d/0x50 kernel/locking/spinlock.c:191 spin_unlock_irqrestore include/linux/spinlock.h:393 [inline] free_debug_processing+0x1b3/0x210 mm/slub.c:1214 __slab_free+0x292/0x400 mm/slub.c:2864 <snip> As a side-effect, with KCSAN, this eventually locks up the console, most likely due to deadlock, e.g. .. -> printk lock -> spinlock_debug -> KCSAN detects data race -> kcsan_print_report() -> printk lock -> deadlock. This fix will 1) avoid the data races, and 2) allow using lock debugging together with KCSAN. Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Marco Elver <elver@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: https://lkml.kernel.org/r/20191120155715.28089-1-elver@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* | lib: spinlock: Trigger a watchdog bite on spin_dump for rwlockPrasad Sodagudi2016-03-22
| | | | | | | | | | | | | | | | | | | | | | Currently dump_stack is printed once a spin_bug is detected for rwlock. So provide an options to trigger a panic or watchdog bite for debugging rwlock magic corruptions and lockups. Change-Id: I20807e8eceb8b81635e58701d1f9f9bd36ab5877 [abhimany: replace msm with qcom] Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org> Signed-off-by: Abhimanyu Kapur <abhimany@codeaurora.org>
* | lib: spinlock: Cause a watchdog bite on spin_dumpRohit Vaswani2016-03-22
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently we cause a BUG_ON once a spin_bug is detected, but that causes a whole lot of processing and the other CPUs would have proceeded to perform other actions and the state of the system is moved by the time we can analyze it. Provide an option to trigger a watchdog bite instead so that we can get the traces as close to the issue as possible. Change-Id: Ic8d692ebd02c6940a3b4e5798463744db20b0026 Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
* | lib: spinlock_debug: Prevent continuous spin dump logs on panicRohit Vaswani2016-03-22
| | | | | | | | | | | | | | | | | | | | | | | | Once a spinlock lockup is detected on a CPU, we invoke a Kernel Panic. During the panic handling, we might see more instances of spinlock lockup from other CPUs. This causes the dmesg to be cluttered and makes it cumbersome to detect what exactly happened. Call spin_bug instead of calling spin_dump directly. Change-Id: I57857a991345a8dac3cd952463d05129145867a8 Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
* | kernel/lib: add additional debug capabilites for data corruptionSyed Rameez Mustafa2016-03-22
|/ | | | | | | | | | | | | | | Data corruptions in the kernel often end up in system crashes that are easier to debug closer to the time of detection. Specifically, if we do not panic immediately after lock or list corruptions have been detected, the problem context is lost in the ensuing system mayhem. Add support for allowing system crash immediately after such corruptions are detected. The CONFIG option controls the enabling/disabling of the feature. Change-Id: I9b2eb62da506a13007acff63e85e9515145909ff Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org> [abhimany: minor merge conflict resolution] Signed-off-by: Abhimanyu Kapur <abhimany@codeaurora.org>
* locking: Move the spinlock code to kernel/locking/Peter Zijlstra2013-11-06
Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-b81ol0z3mon45m51o131yc9j@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>