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Suzuki K. Poulose b2aa2e250f arm64: perf: reject groups spanning multiple HW PMUs ... commit 8fff105e13 upstream. The perf core implicitly rejects events spanning multiple HW PMUs, as in these cases the event->ctx will differ. However this validation is performed after pmu::event_init() is called in perf_init_event(), and thus pmu::event_init() may be called with a group leader from a different HW PMU. The ARM64 PMU driver does not take this fact into account, and when validating groups assumes that it can call to_arm_pmu(event->pmu) for any HW event. When the event in question is from another HW PMU this is wrong, and results in dereferencing garbage. This patch updates the ARM64 PMU driver to first test for and reject events from other PMUs, moving the to_arm_pmu and related logic after this test. Fixes a crash triggered by perf_fuzzer on Linux-4.0-rc2, with a CCI PMU present: Bad mode in Synchronous Abort handler detected, code 0x86000006 -- IABT (current EL) CPU: 0 PID: 1371 Comm: perf_fuzzer Not tainted 3.19.0+ #249 Hardware name: V2F-1XV7 Cortex-A53x2 SMM (DT) task: ffffffc07c73a280 ti: ffffffc07b0a0000 task.ti: ffffffc07b0a0000 PC is at 0x0 LR is at validate_event+0x90/0xa8 pc : [<0000000000000000>] lr : [<ffffffc000090228>] pstate: 00000145 sp : ffffffc07b0a3ba0 [< (null)>] (null) [<ffffffc0000907d8>] armpmu_event_init+0x174/0x3cc [<ffffffc00015d870>] perf_try_init_event+0x34/0x70 [<ffffffc000164094>] perf_init_event+0xe0/0x10c [<ffffffc000164348>] perf_event_alloc+0x288/0x358 [<ffffffc000164c5c>] SyS_perf_event_open+0x464/0x98c Code: bad PC value Also cleans up the code to use the arm_pmu only when we know that we are dealing with an arm pmu event. Cc: Will Deacon <will.deacon@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Peter Ziljstra (Intel) <peterz@infradead.org> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>		History 2016-11-20 01:17:36 +00:00
..
boot	arm64: dts: Add more serial port nodes in APM X-Gene device tree	2014-06-18 12:41:55 +01:00
configs	arm64: defconfig update for LTP	2014-06-18 12:40:52 +01:00
crypto	crypto: arm64/aes-ctr - fix NULL dereference in tail processing	2016-11-20 01:17:26 +00:00
include	arm64: spinlocks: implement smp_mb__before_spinlock() as smp_mb()	2016-11-20 01:17:24 +00:00
kernel	arm64: perf: reject groups spanning multiple HW PMUs	2016-11-20 01:17:36 +00:00
kvm	arm64: KVM: Fix AArch32 to AArch64 register mapping	2015-12-18 16:06:35 +00:00
lib	arm64: __clear_user: handle exceptions on strb	2014-11-27 11:21:47 +00:00
mm	arm64: debug: unmask PSTATE.D earlier	2016-11-20 01:16:54 +00:00
xen	arm: xen: implement multicall hypercall support.	2014-04-24 13:09:46 +01:00
Kconfig	arm64: errata: add module build workaround for erratum #843419	2015-10-06 11:52:29 +01:00
Kconfig.debug	arm64: remove arch specific earlyprintk	2014-04-24 16:32:27 -07:00
Makefile	arm64: errata: Add -mpc-relative-literal-loads to build flags	2016-02-17 10:22:40 +00:00