4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 81e9fa8bab381f8b6eb04df7cdf0f71994099bd4 ]
The armv8_pmuv3 driver doesn't have a remove function, and when the test 'CONFIG_DEBUG_TEST_DRIVER_REMOVE=y' is enabled, the following Call trace can be seen.
[ 1.424287] Failed to register pmu: armv8_pmuv3, reason -17 [ 1.424870] WARNING: CPU: 0 PID: 1 at ../kernel/events/core.c:11771 perf_event_sysfs_init+0x98/0xdc [ 1.425220] Modules linked in: [ 1.425531] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 4.19.0-rc7-next-20181012-00003-ge7a97b1ad77b-dirty #35 [ 1.425951] Hardware name: linux,dummy-virt (DT) [ 1.426212] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 1.426458] pc : perf_event_sysfs_init+0x98/0xdc [ 1.426720] lr : perf_event_sysfs_init+0x98/0xdc [ 1.426908] sp : ffff00000804bd50 [ 1.427077] x29: ffff00000804bd50 x28: ffff00000934e078 [ 1.427429] x27: ffff000009546000 x26: 0000000000000007 [ 1.427757] x25: ffff000009280710 x24: 00000000ffffffef [ 1.428086] x23: ffff000009408000 x22: 0000000000000000 [ 1.428415] x21: ffff000009136008 x20: ffff000009408730 [ 1.428744] x19: ffff80007b20b400 x18: 000000000000000a [ 1.429075] x17: 0000000000000000 x16: 0000000000000000 [ 1.429418] x15: 0000000000000400 x14: 2e79726f74636572 [ 1.429748] x13: 696420656d617320 x12: 656874206e692065 [ 1.430060] x11: 6d616e20656d6173 x10: 2065687420687469 [ 1.430335] x9 : ffff00000804bd50 x8 : 206e6f7361657220 [ 1.430610] x7 : 2c3376756d705f38 x6 : ffff00000954d7ce [ 1.430880] x5 : 0000000000000000 x4 : 0000000000000000 [ 1.431226] x3 : 0000000000000000 x2 : ffffffffffffffff [ 1.431554] x1 : 4d151327adc50b00 x0 : 0000000000000000 [ 1.431868] Call trace: [ 1.432102] perf_event_sysfs_init+0x98/0xdc [ 1.432382] do_one_initcall+0x6c/0x1a8 [ 1.432637] kernel_init_freeable+0x1bc/0x280 [ 1.432905] kernel_init+0x18/0x160 [ 1.433115] ret_from_fork+0x10/0x18 [ 1.433297] ---[ end trace 27fd415390eb9883 ]---
Rework to set suppress_bind_attrs flag to avoid removing the device when CONFIG_DEBUG_TEST_DRIVER_REMOVE=y, since there's no real reason to remove the armv8_pmuv3 driver.
Cc: Arnd Bergmann arnd@arndb.de Co-developed-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Anders Roxell anders.roxell@linaro.org Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/kernel/perf_event.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index e213f8e867f6..8a91ac067d44 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -1274,6 +1274,7 @@ static struct platform_driver armv8_pmu_driver = { .driver = { .name = ARMV8_PMU_PDEV_NAME, .of_match_table = armv8_pmu_of_device_ids, + .suppress_bind_attrs = true, }, .probe = armv8_pmu_device_probe, };