From bdc5c744c7b6457d18a95c26769dad0e7f480a08 Mon Sep 17 00:00:00 2001 From: Qi Liu Date: Thu, 16 Jul 2020 17:19:25 +0800 Subject: 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 Signed-off-by: Qi Liu Reviewed-by: John Garry Link: https://lore.kernel.org/r/1594891165-8228-1-git-send-email-liuqi115@huawei.com Signed-off-by: Will Deacon --- drivers/perf/fsl_imx8_ddr_perf.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/perf/fsl_imx8_ddr_perf.c') 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, -- cgit v1.2.3-70-g09d2 From f32ed8eb0e3f0d0ef4ddb854554d60ca5863a9f9 Mon Sep 17 00:00:00 2001 From: Qi Liu Date: Fri, 17 Jul 2020 16:49:23 +0800 Subject: drivers/perf: Prevent forced unbinding of PMU drivers Forcefully unbinding PMU drivers during perf sampling will lead to a kernel panic, because the perf upper-layer framework call a NULL pointer in this situation. To solve this issue, "suppress_bind_attrs" should be set to true, so that bind/unbind can be disabled via sysfs and prevent unbinding PMU drivers during perf sampling. Signed-off-by: Qi Liu Reviewed-by: John Garry Link: https://lore.kernel.org/r/1594975763-32966-1-git-send-email-liuqi115@huawei.com Signed-off-by: Will Deacon --- drivers/perf/arm-cci.c | 1 + drivers/perf/arm-ccn.c | 1 + drivers/perf/arm_dsu_pmu.c | 1 + drivers/perf/arm_smmuv3_pmu.c | 1 + drivers/perf/arm_spe_pmu.c | 1 + drivers/perf/fsl_imx8_ddr_perf.c | 1 + drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c | 1 + drivers/perf/hisilicon/hisi_uncore_hha_pmu.c | 1 + drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c | 1 + drivers/perf/qcom_l2_pmu.c | 1 + drivers/perf/qcom_l3_pmu.c | 1 + drivers/perf/thunderx2_pmu.c | 1 + drivers/perf/xgene_pmu.c | 1 + 13 files changed, 13 insertions(+) (limited to 'drivers/perf/fsl_imx8_ddr_perf.c') diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c index 1b8e337a29ca..87c4be9dd412 100644 --- a/drivers/perf/arm-cci.c +++ b/drivers/perf/arm-cci.c @@ -1718,6 +1718,7 @@ static struct platform_driver cci_pmu_driver = { .driver = { .name = DRIVER_NAME, .of_match_table = arm_cci_pmu_matches, + .suppress_bind_attrs = true, }, .probe = cci_pmu_probe, .remove = cci_pmu_remove, diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c index d50edef91f59..7b7d23f25713 100644 --- a/drivers/perf/arm-ccn.c +++ b/drivers/perf/arm-ccn.c @@ -1545,6 +1545,7 @@ static struct platform_driver arm_ccn_driver = { .driver = { .name = "arm-ccn", .of_match_table = arm_ccn_match, + .suppress_bind_attrs = true, }, .probe = arm_ccn_probe, .remove = arm_ccn_remove, diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c index 518d0603e24f..96ed93cc78e6 100644 --- a/drivers/perf/arm_dsu_pmu.c +++ b/drivers/perf/arm_dsu_pmu.c @@ -757,6 +757,7 @@ static struct platform_driver dsu_pmu_driver = { .driver = { .name = DRVNAME, .of_match_table = of_match_ptr(dsu_pmu_of_match), + .suppress_bind_attrs = true, }, .probe = dsu_pmu_device_probe, .remove = dsu_pmu_device_remove, diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c index 90caba56dfbc..4cdb35d166ac 100644 --- a/drivers/perf/arm_smmuv3_pmu.c +++ b/drivers/perf/arm_smmuv3_pmu.c @@ -860,6 +860,7 @@ static void smmu_pmu_shutdown(struct platform_device *pdev) static struct platform_driver smmu_pmu_driver = { .driver = { .name = "arm-smmu-v3-pmcg", + .suppress_bind_attrs = true, }, .probe = smmu_pmu_probe, .remove = smmu_pmu_remove, diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c index d80f48798bce..e51ddb6d63ed 100644 --- a/drivers/perf/arm_spe_pmu.c +++ b/drivers/perf/arm_spe_pmu.c @@ -1226,6 +1226,7 @@ static struct platform_driver arm_spe_pmu_driver = { .driver = { .name = DRVNAME, .of_match_table = of_match_ptr(arm_spe_pmu_of_match), + .suppress_bind_attrs = true, }, .probe = arm_spe_pmu_device_probe, .remove = arm_spe_pmu_device_remove, diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c index 2aed2d96f8ae..397540a4b799 100644 --- a/drivers/perf/fsl_imx8_ddr_perf.c +++ b/drivers/perf/fsl_imx8_ddr_perf.c @@ -707,6 +707,7 @@ static struct platform_driver imx_ddr_pmu_driver = { .driver = { .name = "imx-ddr-pmu", .of_match_table = imx_ddr_pmu_dt_ids, + .suppress_bind_attrs = true, }, .probe = ddr_perf_probe, .remove = ddr_perf_remove, diff --git a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c index 71587f19fcd5..5e3645c96443 100644 --- a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c @@ -419,6 +419,7 @@ static struct platform_driver hisi_ddrc_pmu_driver = { .driver = { .name = "hisi_ddrc_pmu", .acpi_match_table = ACPI_PTR(hisi_ddrc_pmu_acpi_match), + .suppress_bind_attrs = true, }, .probe = hisi_ddrc_pmu_probe, .remove = hisi_ddrc_pmu_remove, diff --git a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c index c199de7b219d..5eb8168029c0 100644 --- a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c @@ -431,6 +431,7 @@ static struct platform_driver hisi_hha_pmu_driver = { .driver = { .name = "hisi_hha_pmu", .acpi_match_table = ACPI_PTR(hisi_hha_pmu_acpi_match), + .suppress_bind_attrs = true, }, .probe = hisi_hha_pmu_probe, .remove = hisi_hha_pmu_remove, diff --git a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c index 567d7e6f69d8..3e8b5eab5514 100644 --- a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c @@ -421,6 +421,7 @@ static struct platform_driver hisi_l3c_pmu_driver = { .driver = { .name = "hisi_l3c_pmu", .acpi_match_table = ACPI_PTR(hisi_l3c_pmu_acpi_match), + .suppress_bind_attrs = true, }, .probe = hisi_l3c_pmu_probe, .remove = hisi_l3c_pmu_remove, diff --git a/drivers/perf/qcom_l2_pmu.c b/drivers/perf/qcom_l2_pmu.c index 21d6991dbe0b..4da37f650f98 100644 --- a/drivers/perf/qcom_l2_pmu.c +++ b/drivers/perf/qcom_l2_pmu.c @@ -1028,6 +1028,7 @@ static struct platform_driver l2_cache_pmu_driver = { .driver = { .name = "qcom-l2cache-pmu", .acpi_match_table = ACPI_PTR(l2_cache_pmu_acpi_match), + .suppress_bind_attrs = true, }, .probe = l2_cache_pmu_probe, .remove = l2_cache_pmu_remove, diff --git a/drivers/perf/qcom_l3_pmu.c b/drivers/perf/qcom_l3_pmu.c index 656e830798d9..9ddb577c542b 100644 --- a/drivers/perf/qcom_l3_pmu.c +++ b/drivers/perf/qcom_l3_pmu.c @@ -814,6 +814,7 @@ static struct platform_driver qcom_l3_cache_pmu_driver = { .driver = { .name = "qcom-l3cache-pmu", .acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match), + .suppress_bind_attrs = true, }, .probe = qcom_l3_cache_pmu_probe, }; diff --git a/drivers/perf/thunderx2_pmu.c b/drivers/perf/thunderx2_pmu.c index 51b31d6ff2c4..aac9823b0c6b 100644 --- a/drivers/perf/thunderx2_pmu.c +++ b/drivers/perf/thunderx2_pmu.c @@ -1017,6 +1017,7 @@ static struct platform_driver tx2_uncore_driver = { .driver = { .name = "tx2-uncore-pmu", .acpi_match_table = ACPI_PTR(tx2_uncore_acpi_match), + .suppress_bind_attrs = true, }, .probe = tx2_uncore_probe, .remove = tx2_uncore_remove, diff --git a/drivers/perf/xgene_pmu.c b/drivers/perf/xgene_pmu.c index 46ee6807d533..edac28cd25dd 100644 --- a/drivers/perf/xgene_pmu.c +++ b/drivers/perf/xgene_pmu.c @@ -1975,6 +1975,7 @@ static struct platform_driver xgene_pmu_driver = { .name = "xgene-pmu", .of_match_table = xgene_pmu_of_match, .acpi_match_table = ACPI_PTR(xgene_pmu_acpi_match), + .suppress_bind_attrs = true, }, }; -- cgit v1.2.3-70-g09d2