diff options
| author | Qi Liu <liuqi115@huawei.com> | 2020-07-16 17:19:25 +0800 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2020-07-16 11:35:24 +0100 |
| commit | bdc5c744c7b6457d18a95c26769dad0e7f480a08 (patch) | |
| tree | 43f782c48ba5afd562d604693fe7c2a209e4b801 | |
| parent | 7c116db24d944ff04a67c8bd89cb32c5cd0894ff (diff) | |
| download | lwn-bdc5c744c7b6457d18a95c26769dad0e7f480a08.tar.gz lwn-bdc5c744c7b6457d18a95c26769dad0e7f480a08.zip | |
drivers/perf: Fix kernel panic when rmmod PMU modules during perf sampling
When users try to remove PMU modules during perf sampling, kernel panic
will happen because the pmu->read() is a NULL pointer here.
INFO on HiSilicon hip08 platform as follow:
pc : hisi_uncore_pmu_event_update+0x30/0xa4 [hisi_uncore_pmu]
lr : hisi_uncore_pmu_read+0x20/0x2c [hisi_uncore_pmu]
sp : ffff800010103e90
x29: ffff800010103e90 x28: ffff0027db0c0e40
x27: ffffa29a76f129d8 x26: ffffa29a77ceb000
x25: ffffa29a773a5000 x24: ffffa29a77392000
x23: ffffddffe5943f08 x22: ffff002784285960
x21: ffff002784285800 x20: ffff0027d2e76c80
x19: ffff0027842859e0 x18: ffff80003498bcc8
x17: ffffa29a76afe910 x16: ffffa29a7583f530
x15: 16151a1512061a1e x14: 0000000000000000
x13: ffffa29a76f1e238 x12: 0000000000000001
x11: 0000000000000400 x10: 00000000000009f0
x9 : ffff8000107b3e70 x8 : ffff0027db0c1890
x7 : ffffa29a773a7000 x6 : 00000007f5131013
x5 : 00000007f5131013 x4 : 09f257d417c00000
x3 : 00000002187bd7ce x2 : ffffa29a38f0f0d8
x1 : ffffa29a38eae268 x0 : ffff0027d2e76c80
Call trace:
hisi_uncore_pmu_event_update+0x30/0xa4 [hisi_uncore_pmu]
hisi_uncore_pmu_read+0x20/0x2c [hisi_uncore_pmu]
__perf_event_read+0x1a0/0x1f8
flush_smp_call_function_queue+0xa0/0x160
generic_smp_call_function_single_interrupt+0x18/0x20
handle_IPI+0x31c/0x4dc
gic_handle_irq+0x2c8/0x310
el1_irq+0xcc/0x180
arch_cpu_idle+0x4c/0x20c
default_idle_call+0x20/0x30
do_idle+0x1b4/0x270
cpu_startup_entry+0x28/0x30
secondary_start_kernel+0x1a4/0x1fc
To solve the above issue, current module should be registered to kernel,
so that try_module_get() can be invoked when perf sampling starts. This
adds the reference counting of module and could prevent users from removing
modules during sampling.
Reported-by: Haifeng Wang <wang.wanghaifeng@huawei.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1594891165-8228-1-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
| -rw-r--r-- | drivers/perf/arm_smmuv3_pmu.c | 1 | ||||
| -rw-r--r-- | drivers/perf/fsl_imx8_ddr_perf.c | 1 | ||||
| -rw-r--r-- | drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c | 1 | ||||
| -rw-r--r-- | drivers/perf/hisilicon/hisi_uncore_hha_pmu.c | 1 | ||||
| -rw-r--r-- | drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c | 1 |
5 files changed, 5 insertions, 0 deletions
diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c index 48e28ef93a70..90caba56dfbc 100644 --- a/drivers/perf/arm_smmuv3_pmu.c +++ b/drivers/perf/arm_smmuv3_pmu.c @@ -742,6 +742,7 @@ static int smmu_pmu_probe(struct platform_device *pdev) platform_set_drvdata(pdev, smmu_pmu); smmu_pmu->pmu = (struct pmu) { + .module = THIS_MODULE, .task_ctx_nr = perf_invalid_context, .pmu_enable = smmu_pmu_enable, .pmu_disable = smmu_pmu_disable, diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c index 90884d14f95f..2aed2d96f8ae 100644 --- a/drivers/perf/fsl_imx8_ddr_perf.c +++ b/drivers/perf/fsl_imx8_ddr_perf.c @@ -512,6 +512,7 @@ static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base, { *pmu = (struct ddr_pmu) { .pmu = (struct pmu) { + .module = THIS_MODULE, .capabilities = PERF_PMU_CAP_NO_EXCLUDE, .task_ctx_nr = perf_invalid_context, .attr_groups = attr_groups, diff --git a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c index 15713faaa07e..71587f19fcd5 100644 --- a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c @@ -378,6 +378,7 @@ static int hisi_ddrc_pmu_probe(struct platform_device *pdev) ddrc_pmu->sccl_id, ddrc_pmu->index_id); ddrc_pmu->pmu = (struct pmu) { .name = name, + .module = THIS_MODULE, .task_ctx_nr = perf_invalid_context, .event_init = hisi_uncore_pmu_event_init, .pmu_enable = hisi_uncore_pmu_enable, diff --git a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c index dcc5600788a9..c199de7b219d 100644 --- a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c @@ -390,6 +390,7 @@ static int hisi_hha_pmu_probe(struct platform_device *pdev) hha_pmu->sccl_id, hha_pmu->index_id); hha_pmu->pmu = (struct pmu) { .name = name, + .module = THIS_MODULE, .task_ctx_nr = perf_invalid_context, .event_init = hisi_uncore_pmu_event_init, .pmu_enable = hisi_uncore_pmu_enable, diff --git a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c index 7719ae4e2c56..567d7e6f69d8 100644 --- a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c @@ -380,6 +380,7 @@ static int hisi_l3c_pmu_probe(struct platform_device *pdev) l3c_pmu->sccl_id, l3c_pmu->index_id); l3c_pmu->pmu = (struct pmu) { .name = name, + .module = THIS_MODULE, .task_ctx_nr = perf_invalid_context, .event_init = hisi_uncore_pmu_event_init, .pmu_enable = hisi_uncore_pmu_enable, |