linux-stable.git/arch/arm64/kernel/debug-monitors.c, branch v4.5 Linux kernel stable tree arm64: debug: re-enable irqs before sending breakpoint SIGTRAP 2016-02-10T16:05:28+00:00 Will Deacon will.deacon@arm.com 2016-02-10T16:05:28+00:00 e04a28d45ff343b47a4ffc4dee3a3e279e76ddfa force_sig_info can sleep under an -rt kernel, so attempting to send a breakpoint SIGTRAP with interrupts disabled yields the following BUG: BUG: sleeping function called from invalid context at /kernel-source/kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 551, name: test.sh CPU: 5 PID: 551 Comm: test.sh Not tainted 4.1.13-rt13 #7 Hardware name: Freescale Layerscape 2085a RDB Board (DT) Call trace: dump_backtrace+0x0/0x128 show_stack+0x24/0x30 dump_stack+0x80/0xa0 ___might_sleep+0x128/0x1a0 rt_spin_lock+0x2c/0x40 force_sig_info+0xcc/0x210 brk_handler.part.2+0x6c/0x80 brk_handler+0xd8/0xe8 do_debug_exception+0x58/0xb8 This patch fixes the problem by ensuring that interrupts are enabled prior to sending the SIGTRAP if they were already enabled in the user context. Reported-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
force_sig_info can sleep under an -rt kernel, so attempting to send a
breakpoint SIGTRAP with interrupts disabled yields the following BUG:

  BUG: sleeping function called from invalid context at
  /kernel-source/kernel/locking/rtmutex.c:917
  in_atomic(): 0, irqs_disabled(): 128, pid: 551, name: test.sh
  CPU: 5 PID: 551 Comm: test.sh Not tainted 4.1.13-rt13 #7
  Hardware name: Freescale Layerscape 2085a RDB Board (DT)
  Call trace:
	 dump_backtrace+0x0/0x128
	 show_stack+0x24/0x30
	 dump_stack+0x80/0xa0
	 ___might_sleep+0x128/0x1a0
	 rt_spin_lock+0x2c/0x40
	 force_sig_info+0xcc/0x210
	 brk_handler.part.2+0x6c/0x80
	 brk_handler+0xd8/0xe8
	 do_debug_exception+0x58/0xb8

This patch fixes the problem by ensuring that interrupts are enabled
prior to sending the SIGTRAP if they were already enabled in the user
context.

Reported-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Merge tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core 2015-11-05T05:50:37+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-11-05T05:50:37+00:00 e880e87488d5bbf630dd716e6de8a53585614568 Pull driver core updates from Greg KH: "Here's the "big" driver core updates for 4.4-rc1. Primarily a bunch of debugfs updates, with a smattering of minor driver core fixes and updates as well. All have been in linux-next for a long time" * tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: debugfs: Add debugfs_create_ulong() of: to support binding numa node to specified device in devicetree debugfs: Add read-only/write-only bool file ops debugfs: Add read-only/write-only size_t file ops debugfs: Add read-only/write-only x64 file ops debugfs: Consolidate file mode checks in debugfs_create_*() Revert "mm: Check if section present during memory block (un)registering" driver-core: platform: Provide helpers for multi-driver modules mm: Check if section present during memory block (un)registering devres: fix a for loop bounds check CMA: fix CONFIG_CMA_SIZE_MBYTES overflow in 64bit base/platform: assert that dev_pm_domain callbacks are called unconditionally sysfs: correctly handle short reads on PREALLOC attrs. base: soc: siplify ida usage kobject: move EXPORT_SYMBOL() macros next to corresponding definitions kobject: explain what kobject's sd field is debugfs: document that debugfs_remove*() accepts NULL and error values debugfs: Pass bool pointer to debugfs_create_bool() ACPI / EC: Fix broken 64bit big-endian users of 'global_lock' 
Pull driver core updates from Greg KH:
 "Here's the "big" driver core updates for 4.4-rc1.  Primarily a bunch
  of debugfs updates, with a smattering of minor driver core fixes and
  updates as well.

  All have been in linux-next for a long time"

* tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  debugfs: Add debugfs_create_ulong()
  of: to support binding numa node to specified device in devicetree
  debugfs: Add read-only/write-only bool file ops
  debugfs: Add read-only/write-only size_t file ops
  debugfs: Add read-only/write-only x64 file ops
  debugfs: Consolidate file mode checks in debugfs_create_*()
  Revert "mm: Check if section present during memory block (un)registering"
  driver-core: platform: Provide helpers for multi-driver modules
  mm: Check if section present during memory block (un)registering
  devres: fix a for loop bounds check
  CMA: fix CONFIG_CMA_SIZE_MBYTES overflow in 64bit
  base/platform: assert that dev_pm_domain callbacks are called unconditionally
  sysfs: correctly handle short reads on PREALLOC attrs.
  base: soc: siplify ida usage
  kobject: move EXPORT_SYMBOL() macros next to corresponding definitions
  kobject: explain what kobject's sd field is
  debugfs: document that debugfs_remove*() accepts NULL and error values
  debugfs: Pass bool pointer to debugfs_create_bool()
  ACPI / EC: Fix broken 64bit big-endian users of 'global_lock'
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 2015-11-04T22:47:13+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-11-04T22:47:13+00:00 2dc10ad81fc017837037e60439662e1b16bdffb9 Pull arm64 updates from Catalin Marinas: - "genirq: Introduce generic irq migration for cpu hotunplugged" patch merged from tip/irq/for-arm to allow the arm64-specific part to be upstreamed via the arm64 tree - CPU feature detection reworked to cope with heterogeneous systems where CPUs may not have exactly the same features. The features reported by the kernel via internal data structures or ELF_HWCAP are delayed until all the CPUs are up (and before user space starts) - Support for 16KB pages, with the additional bonus of a 36-bit VA space, though the latter only depending on EXPERT - Implement native {relaxed, acquire, release} atomics for arm64 - New ASID allocation algorithm which avoids IPI on roll-over, together with TLB invalidation optimisations (using local vs global where feasible) - KASan support for arm64 - EFI_STUB clean-up and isolation for the kernel proper (required by KASan) - copy_{to,from,in}_user optimisations (sharing the memcpy template) - perf: moving arm64 to the arm32/64 shared PMU framework - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware - Support for the contiguous PTE hint on kernel mapping (16 consecutive entries may be able to use a single TLB entry) - Generic CONFIG_HZ now used on arm64 - defconfig updates * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits) arm64/efi: fix libstub build under CONFIG_MODVERSIONS ARM64: Enable multi-core scheduler support by default arm64/efi: move arm64 specific stub C code to libstub arm64: page-align sections for DEBUG_RODATA arm64: Fix build with CONFIG_ZONE_DMA=n arm64: Fix compat register mappings arm64: Increase the max granular size arm64: remove bogus TASK_SIZE_64 check arm64: make Timer Interrupt Frequency selectable arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED arm64: cachetype: fix definitions of ICACHEF_* flags arm64: cpufeature: declare enable_cpu_capabilities as static genirq: Make the cpuhotplug migration code less noisy arm64: Constify hwcap name string arrays arm64/kvm: Make use of the system wide safe values arm64/debug: Make use of the system wide safe value arm64: Move FP/ASIMD hwcap handling to common code arm64/HWCAP: Use system wide safe values arm64/capabilities: Make use of system wide safe value arm64: Delay cpu feature capability checks ... 
Pull arm64 updates from Catalin Marinas:

 - "genirq: Introduce generic irq migration for cpu hotunplugged" patch
   merged from tip/irq/for-arm to allow the arm64-specific part to be
   upstreamed via the arm64 tree

 - CPU feature detection reworked to cope with heterogeneous systems
   where CPUs may not have exactly the same features.  The features
   reported by the kernel via internal data structures or ELF_HWCAP are
   delayed until all the CPUs are up (and before user space starts)

 - Support for 16KB pages, with the additional bonus of a 36-bit VA
   space, though the latter only depending on EXPERT

 - Implement native {relaxed, acquire, release} atomics for arm64

 - New ASID allocation algorithm which avoids IPI on roll-over, together
   with TLB invalidation optimisations (using local vs global where
   feasible)

 - KASan support for arm64

 - EFI_STUB clean-up and isolation for the kernel proper (required by
   KASan)

 - copy_{to,from,in}_user optimisations (sharing the memcpy template)

 - perf: moving arm64 to the arm32/64 shared PMU framework

 - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware

 - Support for the contiguous PTE hint on kernel mapping (16 consecutive
   entries may be able to use a single TLB entry)

 - Generic CONFIG_HZ now used on arm64

 - defconfig updates

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits)
  arm64/efi: fix libstub build under CONFIG_MODVERSIONS
  ARM64: Enable multi-core scheduler support by default
  arm64/efi: move arm64 specific stub C code to libstub
  arm64: page-align sections for DEBUG_RODATA
  arm64: Fix build with CONFIG_ZONE_DMA=n
  arm64: Fix compat register mappings
  arm64: Increase the max granular size
  arm64: remove bogus TASK_SIZE_64 check
  arm64: make Timer Interrupt Frequency selectable
  arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED
  arm64: cachetype: fix definitions of ICACHEF_* flags
  arm64: cpufeature: declare enable_cpu_capabilities as static
  genirq: Make the cpuhotplug migration code less noisy
  arm64: Constify hwcap name string arrays
  arm64/kvm: Make use of the system wide safe values
  arm64/debug: Make use of the system wide safe value
  arm64: Move FP/ASIMD hwcap handling to common code
  arm64/HWCAP: Use system wide safe values
  arm64/capabilities: Make use of system wide safe value
  arm64: Delay cpu feature capability checks
  ...
arm64/debug: Make use of the system wide safe value 2015-10-21T14:35:59+00:00 Suzuki K. Poulose suzuki.poulose@arm.com 2015-10-19T13:24:54+00:00 3085bb01b40676d946a13064483ab2819ae3b010 Use the system wide value of ID_AA64DFR0 to make safer decisions Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Use the system wide value of ID_AA64DFR0 to make safer decisions

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: debug: Fix typo in debug-monitors.c 2015-10-16T17:21:12+00:00 Yang Shi yang.shi@linaro.org 2015-09-18T21:09:00+00:00 fbc61a26e6b7a2ebc399559ea22df4a35ac05fcb Fix handers to handlers. Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Fix handers to handlers.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: replace read_lock to rcu lock in call_break_hook 2015-10-06T18:10:28+00:00 Yang Shi yang.shi@linaro.org 2015-10-05T21:32:51+00:00 62c6c61adbc623cdacf74b8f29c278e539060c48 BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 342, name: perf 1 lock held by perf/342: #0: (break_hook_lock){+.+...}, at: [<ffffffc0000851ac>] call_break_hook+0x34/0xd0 irq event stamp: 62224 hardirqs last enabled at (62223): [<ffffffc00010b7bc>] __call_rcu.constprop.59+0x104/0x270 hardirqs last disabled at (62224): [<ffffffc0000fbe20>] vprintk_emit+0x68/0x640 softirqs last enabled at (0): [<ffffffc000097928>] copy_process.part.8+0x428/0x17f8 softirqs last disabled at (0): [< (null)>] (null) CPU: 0 PID: 342 Comm: perf Not tainted 4.1.6-rt5 #4 Hardware name: linux,dummy-virt (DT) Call trace: [<ffffffc000089968>] dump_backtrace+0x0/0x128 [<ffffffc000089ab0>] show_stack+0x20/0x30 [<ffffffc0007030d0>] dump_stack+0x7c/0xa0 [<ffffffc0000c878c>] ___might_sleep+0x174/0x260 [<ffffffc000708ac8>] __rt_spin_lock+0x28/0x40 [<ffffffc000708db0>] rt_read_lock+0x60/0x80 [<ffffffc0000851a8>] call_break_hook+0x30/0xd0 [<ffffffc000085a70>] brk_handler+0x30/0x98 [<ffffffc000082248>] do_debug_exception+0x50/0xb8 Exception stack(0xffffffc00514fe30 to 0xffffffc00514ff50) fe20: 00000000 00000000 c1594680 0000007f fe40: ffffffff ffffffff 92063940 0000007f 0550dcd8 ffffffc0 00000000 00000000 fe60: 0514fe70 ffffffc0 000be1f8 ffffffc0 0514feb0 ffffffc0 0008948c ffffffc0 fe80: 00000004 00000000 0514fed0 ffffffc0 ffffffff ffffffff 9282a948 0000007f fea0: 00000000 00000000 9282b708 0000007f c1592820 0000007f 00083914 ffffffc0 fec0: 00000000 00000000 00000010 00000000 00000064 00000000 00000001 00000000 fee0: 005101e0 00000000 c1594680 0000007f c1594740 0000007f ffffffd8 ffffff80 ff00: 00000000 00000000 00000000 00000000 c1594770 0000007f c1594770 0000007f ff20: 00665e10 00000000 7f7f7f7f 7f7f7f7f 01010101 01010101 00000000 00000000 ff40: 928e4cc0 0000007f 91ff11e8 0000007f call_break_hook is called in atomic context (hard irq disabled), so replace the sleepable lock to rcu lock, replace relevant list operations to rcu version and call synchronize_rcu() in unregister_break_hook(). And, replace write lock to spinlock in {un}register_break_hook. Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 0, irqs_disabled(): 128, pid: 342, name: perf
1 lock held by perf/342:
 #0:  (break_hook_lock){+.+...}, at: [<ffffffc0000851ac>] call_break_hook+0x34/0xd0
irq event stamp: 62224
hardirqs last  enabled at (62223): [<ffffffc00010b7bc>] __call_rcu.constprop.59+0x104/0x270
hardirqs last disabled at (62224): [<ffffffc0000fbe20>] vprintk_emit+0x68/0x640
softirqs last  enabled at (0): [<ffffffc000097928>] copy_process.part.8+0x428/0x17f8
softirqs last disabled at (0): [<          (null)>]           (null)
CPU: 0 PID: 342 Comm: perf Not tainted 4.1.6-rt5 #4
Hardware name: linux,dummy-virt (DT)
Call trace:
[<ffffffc000089968>] dump_backtrace+0x0/0x128
[<ffffffc000089ab0>] show_stack+0x20/0x30
[<ffffffc0007030d0>] dump_stack+0x7c/0xa0
[<ffffffc0000c878c>] ___might_sleep+0x174/0x260
[<ffffffc000708ac8>] __rt_spin_lock+0x28/0x40
[<ffffffc000708db0>] rt_read_lock+0x60/0x80
[<ffffffc0000851a8>] call_break_hook+0x30/0xd0
[<ffffffc000085a70>] brk_handler+0x30/0x98
[<ffffffc000082248>] do_debug_exception+0x50/0xb8
Exception stack(0xffffffc00514fe30 to 0xffffffc00514ff50)
fe20:                                     00000000 00000000 c1594680 0000007f
fe40: ffffffff ffffffff 92063940 0000007f 0550dcd8 ffffffc0 00000000 00000000
fe60: 0514fe70 ffffffc0 000be1f8 ffffffc0 0514feb0 ffffffc0 0008948c ffffffc0
fe80: 00000004 00000000 0514fed0 ffffffc0 ffffffff ffffffff 9282a948 0000007f
fea0: 00000000 00000000 9282b708 0000007f c1592820 0000007f 00083914 ffffffc0
fec0: 00000000 00000000 00000010 00000000 00000064 00000000 00000001 00000000
fee0: 005101e0 00000000 c1594680 0000007f c1594740 0000007f ffffffd8 ffffff80
ff00: 00000000 00000000 00000000 00000000 c1594770 0000007f c1594770 0000007f
ff20: 00665e10 00000000 7f7f7f7f 7f7f7f7f 01010101 01010101 00000000 00000000
ff40: 928e4cc0 0000007f 91ff11e8 0000007f

call_break_hook is called in atomic context (hard irq disabled), so replace
the sleepable lock to rcu lock, replace relevant list operations to rcu
version and call synchronize_rcu() in unregister_break_hook().

And, replace write lock to spinlock in {un}register_break_hook.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: debug: Fix typo in debug-monitors.c 2015-10-05T15:30:50+00:00 Yang Shi yang.shi@linaro.org 2015-09-18T21:09:00+00:00 95485fdc64b1067e0e88d8c7980eb57994ad450e Fix comment typo: s/handers/handlers/ Signed-off-by: Yang Shi <yang.shi@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
Fix comment typo: s/handers/handlers/

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
debugfs: Pass bool pointer to debugfs_create_bool() 2015-10-04T10:36:07+00:00 Viresh Kumar viresh.kumar@linaro.org 2015-09-26T22:04:07+00:00 621a5f7ad9cd1ce7933f1d302067cbd58354173c Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument, when all it needs is a boolean pointer. It would be better to update this API to make it accept 'bool *' instead, as that will make it more consistent and often more convenient. Over that bool takes just a byte. That required updates to all user sites as well, in the same commit updating the API. regmap core was also using debugfs_{read|write}_file_bool(), directly and variable types were updated for that to be bool as well. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Its a bit odd that debugfs_create_bool() takes 'u32 *' as an argument,
when all it needs is a boolean pointer.

It would be better to update this API to make it accept 'bool *'
instead, as that will make it more consistent and often more convenient.
Over that bool takes just a byte.

That required updates to all user sites as well, in the same commit
updating the API. regmap core was also using
debugfs_{read|write}_file_bool(), directly and variable types were
updated for that to be bool as well.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: cpu hotplug: ensure we mask out CPU_TASKS_FROZEN in notifiers 2015-09-17T10:57:02+00:00 Will Deacon will.deacon@arm.com 2015-09-11T14:31:24+00:00 e56d82a116176f7af9d642b560abbbd3a2b68013 We have a couple of CPU hotplug notifiers for resetting the CPU debug state to a sane value when a CPU comes online. This patch ensures that we mask out CPU_TASKS_FROZEN so that we don't miss any online events occuring due to suspend/resume. Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
We have a couple of CPU hotplug notifiers for resetting the CPU debug
state to a sane value when a CPU comes online.

This patch ensures that we mask out CPU_TASKS_FROZEN so that we don't
miss any online events occuring due to suspend/resume.

Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: debug: rename enum debug_el to avoid symbol collision 2015-07-27T17:36:54+00:00 Will Deacon will.deacon@arm.com 2015-07-27T17:36:54+00:00 6f883d10a18b971a3646303d12ef75138dfd31f9 lib/list_sort.c defines a 'struct debug_el', where "el" is assumedly a a contraction of "element". This conflicts with 'enum debug_el' in our asm/debug-monitors.h header file, where "el" stands for Exception Level. The result is build failure when targetting allmodconfig, so rename our enum to 'dbg_active_el' to be slightly more explicit about what it is. Signed-off-by: Will Deacon <will.deacon@arm.com> 
lib/list_sort.c defines a 'struct debug_el', where "el" is assumedly a
a contraction of "element". This conflicts with 'enum debug_el' in our
asm/debug-monitors.h header file, where "el" stands for Exception Level.

The result is build failure when targetting allmodconfig, so rename our
enum to 'dbg_active_el' to be slightly more explicit about what it is.

Signed-off-by: Will Deacon <will.deacon@arm.com>