kernel/linux.git/arch/powerpc/perf, branch v6.1.168

arch/powerpc/perf: Check the instruction type before creating sample with perf_mem_data_src

2025-06-04T12:40:15+00:00

[ Upstream commit 2ffb26afa64261139e608bf087a0c1fe24d76d4d ] perf mem report aborts as below sometimes (during some corner case) in powerpc: # ./perf mem report 1>out *** stack smashing detected ***: terminated Aborted (core dumped) The backtrace is as below: __pthread_kill_implementation () raise () abort () __libc_message __fortify_fail __stack_chk_fail hist_entry.lvl_snprintf __sort__hpp_entry __hist_entry__snprintf hists.fprintf cmd_report cmd_mem Snippet of code which triggers the issue from tools/perf/util/sort.c static int hist_entry__lvl_snprintf(struct hist_entry *he, char *bf, size_t size, unsigned int width) { char out[64]; perf_mem__lvl_scnprintf(out, sizeof(out), he->mem_info); return repsep_snprintf(bf, size, "%-*s", width, out); } The value of "out" is filled from perf_mem_data_src value. Debugging this further showed that for some corner cases, the value of "data_src" was pointing to wrong value. This resulted in bigger size of string and causing stack check fail. The perf mem data source values are captured in the sample via isa207_get_mem_data_src function. The initial check is to fetch the type of sampled instruction. If the type of instruction is not valid (not a load/store instruction), the function returns. Since 'commit e16fd7f2cb1a ("perf: Use sample_flags for data_src")', data_src field is not initialized by the perf_sample_data_init() function. If the PMU driver doesn't set the data_src value to zero if type is not valid, this will result in uninitailised value for data_src. The uninitailised value of data_src resulted in stack check fail followed by abort for "perf mem report". When requesting for data source information in the sample, the instruction type is expected to be load or store instruction. In ISA v3.0, due to hardware limitation, there are corner cases where the instruction type other than load or store is observed. In ISA v3.0 and before values "0" and "7" are considered reserved. In ISA v3.1, value "7" has been used to indicate "larx/stcx". Drop the sample if instruction type has reserved values for this field with a ISA version check. Initialize data_src to zero in isa207_get_mem_data_src if the instruction type is not load/store. Reported-by: Disha Goel Signed-off-by: Athira Rajeev Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20250121131621.39054-1-atrajeev@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/hv-gpci: Fix the H_GET_PERF_COUNTER_INFO hcall return value checks

2024-03-26T22:20:52+00:00

[ Upstream commit ad86d7ee43b22aa2ed60fb982ae94b285c1be671 ] Running event hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ in one of the system throws below error: ---Logs--- # perf list | grep hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=?/[Kernel PMU event] # perf stat -v -e hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ sleep 2 Using CPUID 00800200 Control descriptor is not initialized Warning: hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ event is not supported by the kernel. failed to read counter hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ Performance counter stats for 'system wide': hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ 2.000700771 seconds time elapsed The above error is because of the hcall failure as required permission "Enable Performance Information Collection" is not set. Based on current code, single_gpci_request function did not check the error type incase hcall fails and by default returns EINVAL. But we can have other reasons for hcall failures like H_AUTHORITY/H_PARAMETER with detail_rc as GEN_BUF_TOO_SMALL, for which we need to act accordingly. Fix this issue by adding new checks in the single_gpci_request and h_gpci_event_init functions. Result after fix patch changes: # perf stat -e hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ sleep 2 Error: No permission to enable hv_gpci/dispatch_timebase_by_processor_processor_time_in_timebase_cycles,phys_processor_idx=0/ event. Fixes: 220a0c609ad1 ("powerpc/perf: Add support for the hv gpci (get performance counter info) interface") Reported-by: Akanksha J N Signed-off-by: Kajol Jain Signed-off-by: Michael Ellerman Link: https://msgid.link/20240229122847.101162-1-kjain@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/imc-pmu: Add a null pointer check in update_events_in_group()

2024-01-25T23:27:19+00:00

[ Upstream commit 0a233867a39078ebb0f575e2948593bbff5826b3 ] kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Fixes: 885dcd709ba9 ("powerpc/perf: Add nest IMC PMU support") Signed-off-by: Kunwu Chan Signed-off-by: Michael Ellerman Link: https://msgid.link/20231126093719.1440305-1-chentao@kylinos.cn Signed-off-by: Sasha Levin

powerpc/perf: Fix disabling BHRB and instruction sampling

2023-11-28T17:07:07+00:00

commit ea142e590aec55ba40c5affb4d49e68c713c63dc upstream. When the PMU is disabled, MMCRA is not updated to disable BHRB and instruction sampling. This can lead to those features remaining enabled, which can slow down a real or emulated CPU. Fixes: 1cade527f6e9 ("powerpc/perf: BHRB control to disable BHRB logic when not used") Cc: stable@vger.kernel.org # v5.9+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20231018153423.298373-1-npiggin@gmail.com Signed-off-by: Greg Kroah-Hartman

powerpc/imc-pmu: Use the correct spinlock initializer.

2023-11-20T10:52:12+00:00

[ Upstream commit 007240d59c11f87ac4f6cfc6a1d116630b6b634c ] The macro __SPIN_LOCK_INITIALIZER() is implementation specific. Users that desire to initialize a spinlock in a struct must use __SPIN_LOCK_UNLOCKED(). Use __SPIN_LOCK_UNLOCKED() for the spinlock_t in imc_global_refc. Fixes: 76d588dddc459 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Michael Ellerman Link: https://msgid.link/20230309134831.Nz12nqsU@linutronix.de Signed-off-by: Sasha Levin

powerpc/perf/hv-24x7: Update domain value check

2023-10-06T12:56:38+00:00

[ Upstream commit 4ff3ba4db5943cac1045e3e4a3c0463ea10f6930 ] Valid domain value is in range 1 to HV_PERF_DOMAIN_MAX. Current code has check for domain value greater than or equal to HV_PERF_DOMAIN_MAX. But the check for domain value 0 is missing. Fix this issue by adding check for domain value 0. Before: # ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1 Using CPUID 00800200 Control descriptor is not initialized Error: The sys_perf_event_open() syscall returned with 5 (Input/output error) for event (hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/). /bin/dmesg | grep -i perf may provide additional information. Result from dmesg: [ 37.819387] hv-24x7: hcall failed: [0 0x60040000 0x100 0] => ret 0xfffffffffffffffc (-4) detail=0x2000000 failing ix=0 After: # ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1 Using CPUID 00800200 Control descriptor is not initialized Warning: hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ event is not supported by the kernel. failed to read counter hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ Fixes: ebd4a5a3ebd9 ("powerpc/perf/hv-24x7: Minor improvements") Reported-by: Krishan Gopal Sarawast Signed-off-by: Kajol Jain Tested-by: Disha Goel Signed-off-by: Michael Ellerman Link: https://msgid.link/20230825055601.360083-1-kjain@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/perf: Convert fsl_emb notifier to state machine callbacks

2023-09-13T07:42:47+00:00

[ Upstream commit 34daf445f82bd3a4df852bb5f1dffd792ac830a0 ] CC arch/powerpc/perf/core-fsl-emb.o arch/powerpc/perf/core-fsl-emb.c:675:6: error: no previous prototype for 'hw_perf_event_setup' [-Werror=missing-prototypes] 675 | void hw_perf_event_setup(int cpu) | ^~~~~~~~~~~~~~~~~~~ Looks like fsl_emb was completely missed by commit 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") So, apply same changes as commit 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") then commit 57ecde42cc74 ("powerpc/perf: Convert book3s notifier to state machine callbacks") While at it, also fix following error: arch/powerpc/perf/core-fsl-emb.c: In function 'perf_event_interrupt': arch/powerpc/perf/core-fsl-emb.c:648:13: error: variable 'found' set but not used [-Werror=unused-but-set-variable] 648 | int found = 0; | ^~~~~ Fixes: 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks") Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/603e1facb32608f88f40b7d7b9094adc50e7b2dc.1692349125.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin

powerpc/perf: Properly detect mpc7450 family

2023-05-11T14:03:31+00:00

[ Upstream commit e7299f961fe5e4496db0bfaa9e819f5e97f3846b ] Unlike PVR_POWER8, etc ...., PVR_7450 represents a full PVR value and not a family value. To avoid confusion, do like E500 family and define the relevant PVR_VER_xxxx values for the 7450 family: 0x8000 ==> 7450 0x8001 ==> 7455 0x8002 ==> 7447 0x8003 ==> 7447A 0x8004 ==> 7448 And use them to detect 7450 family for perf events. Reported-by: kernel test robot Reported-by: Dan Carpenter Link: https://lore.kernel.org/r/202302260657.7dM9Uwev-lkp@intel.com/ Fixes: ec3eb9d941a9 ("powerpc/perf: Use PVR rather than oprofile field to determine CPU version") Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/99ca1da2e5a6cf82a8abf4bc034918e500e31781.1677513277.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin

powerpc/imc-pmu: Revert nest_init_lock to being a mutex

2023-02-09T10:28:26+00:00

commit ad53db4acb415976761d7302f5b02e97f2bd097e upstream. The recent commit 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") fixed warnings (and possible deadlocks) in the IMC PMU driver by converting the locking to use spinlocks. It also converted the init-time nest_init_lock to a spinlock, even though it's not used at runtime in IRQ disabled sections or while holding other spinlocks. This leads to warnings such as: BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 1, expected: 0 CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc2-14719-gf12cd06109f4-dirty #1 Hardware name: Mambo,Simulated-System POWER9 0x4e1203 opal:v6.6.6 PowerNV Call Trace: dump_stack_lvl+0x74/0xa8 (unreliable) __might_resched+0x178/0x1a0 __cpuhp_setup_state+0x64/0x1e0 init_imc_pmu+0xe48/0x1250 opal_imc_counters_probe+0x30c/0x6a0 platform_probe+0x78/0x110 really_probe+0x104/0x420 __driver_probe_device+0xb0/0x170 driver_probe_device+0x58/0x180 __driver_attach+0xd8/0x250 bus_for_each_dev+0xb4/0x140 driver_attach+0x34/0x50 bus_add_driver+0x1e8/0x2d0 driver_register+0xb4/0x1c0 __platform_driver_register+0x38/0x50 opal_imc_driver_init+0x2c/0x40 do_one_initcall+0x80/0x360 kernel_init_freeable+0x310/0x3b8 kernel_init+0x30/0x1a0 ret_from_kernel_thread+0x5c/0x64 Fix it by converting nest_init_lock back to a mutex, so that we can call sleeping functions while holding it. There is no interaction between nest_init_lock and the runtime spinlocks used by the actual PMU routines. Fixes: 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") Tested-by: Kajol Jain Reviewed-by: Kajol Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230130014401.540543-1-mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman

powerpc/imc-pmu: Fix use of mutex in IRQs disabled section

2023-01-18T10:58:21+00:00

commit 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream. Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event. Command to trigger the warning: # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5 Performance counter stats for 'sleep 5': 0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ 5.002117947 seconds time elapsed 0.000131000 seconds user 0.001063000 seconds sys Below is snippet of the warning in dmesg: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec preempt_count: 2, expected: 0 4 locks held by perf-exec/2869: #0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90 #1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0 #2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510 #3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510 irq event stamp: 4806 hardirqs last enabled at (4805): [] _raw_spin_unlock_irqrestore+0x94/0xd0 hardirqs last disabled at (4806): [] perf_event_exec+0x394/0x510 softirqs last enabled at (0): [] copy_process+0xc34/0x1ff0 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV Call Trace: dump_stack_lvl+0x98/0xe0 (unreliable) __might_resched+0x2f8/0x310 __mutex_lock+0x6c/0x13f0 thread_imc_event_add+0xf4/0x1b0 event_sched_in+0xe0/0x210 merge_sched_in+0x1f0/0x600 visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0 ctx_flexible_sched_in+0xcc/0x140 ctx_sched_in+0x20c/0x2a0 ctx_resched+0x104/0x1c0 perf_event_exec+0x340/0x510 begin_new_exec+0x730/0xef0 load_elf_binary+0x3f8/0x1e10 ... do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0 WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0 CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670 REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2) MSR: 9000000000021033 CR: 48002824 XER: 00000000 CFAR: c00000000013fb64 IRQMASK: 1 The above warning triggered because the current imc-pmu code uses mutex lock in interrupt disabled sections. The function mutex_lock() internally calls __might_resched(), which will check if IRQs are disabled and in case IRQs are disabled, it will trigger the warning. Fix the issue by changing the mutex lock to spinlock. Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device") Reported-by: Michael Petlan Reported-by: Peter Zijlstra Signed-off-by: Kajol Jain [mpe: Fix comments, trim oops in change log, add reported-by tags] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com Signed-off-by: Greg Kroah-Hartman