From 8c218578fcbbbdb10416c8614658bf32e3bf1655 Mon Sep 17 00:00:00 2001 From: Madhavan Srinivasan Date: Fri, 26 May 2017 13:38:27 +0530 Subject: powerpc/perf: Fix Power9 test_adder fields Commit 8d911904f3ce4 ('powerpc/perf: Add restrictions to PMC5 in power9 DD1') was added to restrict the use of PMC5 in Power9 DD1. Intention was to disable the use of PMC5 using raw event code. But instead of updating the power9_isa207_pmu structure (used on DD1), the commit incorrectly updated the power9_pmu structure. Fix it. Fixes: 8d911904f3ce ("powerpc/perf: Add restrictions to PMC5 in power9 DD1") Reported-by: Shriya Signed-off-by: Madhavan Srinivasan Tested-by: Shriya Signed-off-by: Michael Ellerman --- arch/powerpc/perf/power9-pmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/perf') diff --git a/arch/powerpc/perf/power9-pmu.c b/arch/powerpc/perf/power9-pmu.c index 018f8e90ac35..bb28e1a41257 100644 --- a/arch/powerpc/perf/power9-pmu.c +++ b/arch/powerpc/perf/power9-pmu.c @@ -402,7 +402,7 @@ static struct power_pmu power9_isa207_pmu = { .name = "POWER9", .n_counter = MAX_PMU_COUNTERS, .add_fields = ISA207_ADD_FIELDS, - .test_adder = ISA207_TEST_ADDER, + .test_adder = P9_DD1_TEST_ADDER, .compute_mmcr = isa207_compute_mmcr, .config_bhrb = power9_config_bhrb, .bhrb_filter_map = power9_bhrb_filter_map, @@ -421,7 +421,7 @@ static struct power_pmu power9_pmu = { .name = "POWER9", .n_counter = MAX_PMU_COUNTERS, .add_fields = ISA207_ADD_FIELDS, - .test_adder = P9_DD1_TEST_ADDER, + .test_adder = ISA207_TEST_ADDER, .compute_mmcr = isa207_compute_mmcr, .config_bhrb = power9_config_bhrb, .bhrb_filter_map = power9_bhrb_filter_map, -- cgit v1.2.3-55-g7522 From bf05fc25f268cd62f147f368fe65ad3e5b04fe9f Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Thu, 15 Jun 2017 19:16:48 +0530 Subject: powerpc/perf: Fix oops when kthread execs user process When a kthread calls call_usermodehelper() the steps are: 1. allocate current->mm 2. load_elf_binary() 3. populate current->thread.regs While doing this, interrupts are not disabled. If there is a perf interrupt in the middle of this process (i.e. step 1 has completed but not yet reached to step 3) and if perf tries to read userspace regs, kernel oops with following log: Unable to handle kernel paging request for data at address 0x00000000 Faulting instruction address: 0xc0000000000da0fc ... Call Trace: perf_output_sample_regs+0x6c/0xd0 perf_output_sample+0x4e4/0x830 perf_event_output_forward+0x64/0x90 __perf_event_overflow+0x8c/0x1e0 record_and_restart+0x220/0x5c0 perf_event_interrupt+0x2d8/0x4d0 performance_monitor_exception+0x54/0x70 performance_monitor_common+0x158/0x160 --- interrupt: f01 at avtab_search_node+0x150/0x1a0 LR = avtab_search_node+0x100/0x1a0 ... load_elf_binary+0x6e8/0x15a0 search_binary_handler+0xe8/0x290 do_execveat_common.isra.14+0x5f4/0x840 call_usermodehelper_exec_async+0x170/0x210 ret_from_kernel_thread+0x5c/0x7c Fix it by setting abi to PERF_SAMPLE_REGS_ABI_NONE when userspace pt_regs are not set. Fixes: ed4a4ef85cf5 ("powerpc/perf: Add support for sampling interrupt register state") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Ravi Bangoria Acked-by: Naveen N. Rao Signed-off-by: Michael Ellerman --- arch/powerpc/perf/perf_regs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/perf') diff --git a/arch/powerpc/perf/perf_regs.c b/arch/powerpc/perf/perf_regs.c index cbd82fde5770..09ceea6175ba 100644 --- a/arch/powerpc/perf/perf_regs.c +++ b/arch/powerpc/perf/perf_regs.c @@ -101,5 +101,6 @@ void perf_get_regs_user(struct perf_regs *regs_user, struct pt_regs *regs_user_copy) { regs_user->regs = task_pt_regs(current); - regs_user->abi = perf_reg_abi(current); + regs_user->abi = (regs_user->regs) ? perf_reg_abi(current) : + PERF_SAMPLE_REGS_ABI_NONE; } -- cgit v1.2.3-55-g7522