On Thu, 2019-11-14 at 13:17 +0000, Lukasz Luba wrote: > Hi Greg, > > This patch causes a deadlock, the thermal framework stops. Please > check > this fix (I found it before posting exactly the same solution): > https://lkml.org/lkml/2019/11/12/1075 > > I have verified it on OdroidXU4 and it works. It needs some cleaning > in > the commit message, though. > I have added to CC the author: Wei Wang > > I don't know in how many stable trees it was applied, but should be > fix > there also. > Right. I've just applied this in thermal tree, will check if it can get 5.4 or not later. thanks, rui > Regards, > Lukasz Luba > > On 10/10/19 9:36 AM, Greg Kroah-Hartman wrote: > > From: Ido Schimmel <idosch@xxxxxxxxxxxx> > > > > [ Upstream commit 1851799e1d2978f68eea5d9dff322e121dcf59c1 ] > > > > thermal_zone_device_unregister() cancels the delayed work that > > polls the > > thermal zone, but it does not wait for it to finish. This is racy > > with > > respect to the freeing of the thermal zone device, which can result > > in a > > use-after-free [1]. > > > > Fix this by waiting for the delayed work to finish before freeing > > the > > thermal zone device. Note that thermal_zone_device_set_polling() is > > never invoked from an atomic context, so it is safe to call > > cancel_delayed_work_sync() that can block. > > > > [1] > > [ +0.002221] > > ================================================================== > > [ +0.000064] BUG: KASAN: use-after-free in > > __mutex_lock+0x1076/0x11c0 > > [ +0.000016] Read of size 8 at addr ffff8881e48e0450 by task > > kworker/1:0/17 > > > > [ +0.000023] CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.2.0- > > rc6-custom-02495-g8e73ca3be4af #1701 > > [ +0.000010] Hardware name: Mellanox Technologies Ltd. MSN2100- > > CB2FO/SA001017, BIOS 5.6.5 06/07/2016 > > [ +0.000016] Workqueue: events_freezable_power_ > > thermal_zone_device_check > > [ +0.000012] Call Trace: > > [ +0.000021] dump_stack+0xa9/0x10e > > [ +0.000020] print_address_description.cold.2+0x9/0x25e > > [ +0.000018] __kasan_report.cold.3+0x78/0x9d > > [ +0.000016] kasan_report+0xe/0x20 > > [ +0.000016] __mutex_lock+0x1076/0x11c0 > > [ +0.000014] step_wise_throttle+0x72/0x150 > > [ +0.000018] handle_thermal_trip+0x167/0x760 > > [ +0.000019] thermal_zone_device_update+0x19e/0x5f0 > > [ +0.000019] process_one_work+0x969/0x16f0 > > [ +0.000017] worker_thread+0x91/0xc40 > > [ +0.000014] kthread+0x33d/0x400 > > [ +0.000015] ret_from_fork+0x3a/0x50 > > > > [ +0.000020] Allocated by task 1: > > [ +0.000015] save_stack+0x19/0x80 > > [ +0.000015] __kasan_kmalloc.constprop.4+0xc1/0xd0 > > [ +0.000014] kmem_cache_alloc_trace+0x152/0x320 > > [ +0.000015] thermal_zone_device_register+0x1b4/0x13a0 > > [ +0.000015] mlxsw_thermal_init+0xc92/0x23d0 > > [ +0.000014] __mlxsw_core_bus_device_register+0x659/0x11b0 > > [ +0.000013] mlxsw_core_bus_device_register+0x3d/0x90 > > [ +0.000013] mlxsw_pci_probe+0x355/0x4b0 > > [ +0.000014] local_pci_probe+0xc3/0x150 > > [ +0.000013] pci_device_probe+0x280/0x410 > > [ +0.000013] really_probe+0x26a/0xbb0 > > [ +0.000013] driver_probe_device+0x208/0x2e0 > > [ +0.000013] device_driver_attach+0xfe/0x140 > > [ +0.000013] __driver_attach+0x110/0x310 > > [ +0.000013] bus_for_each_dev+0x14b/0x1d0 > > [ +0.000013] driver_register+0x1c0/0x400 > > [ +0.000015] mlxsw_sp_module_init+0x5d/0xd3 > > [ +0.000014] do_one_initcall+0x239/0x4dd > > [ +0.000013] kernel_init_freeable+0x42b/0x4e8 > > [ +0.000012] kernel_init+0x11/0x18b > > [ +0.000013] ret_from_fork+0x3a/0x50 > > > > [ +0.000015] Freed by task 581: > > [ +0.000013] save_stack+0x19/0x80 > > [ +0.000014] __kasan_slab_free+0x125/0x170 > > [ +0.000013] kfree+0xf3/0x310 > > [ +0.000013] thermal_release+0xc7/0xf0 > > [ +0.000014] device_release+0x77/0x200 > > [ +0.000014] kobject_put+0x1a8/0x4c0 > > [ +0.000014] device_unregister+0x38/0xc0 > > [ +0.000014] thermal_zone_device_unregister+0x54e/0x6a0 > > [ +0.000014] mlxsw_thermal_fini+0x184/0x35a > > [ +0.000014] mlxsw_core_bus_device_unregister+0x10a/0x640 > > [ +0.000013] mlxsw_devlink_core_bus_device_reload+0x92/0x210 > > [ +0.000015] devlink_nl_cmd_reload+0x113/0x1f0 > > [ +0.000014] genl_family_rcv_msg+0x700/0xee0 > > [ +0.000013] genl_rcv_msg+0xca/0x170 > > [ +0.000013] netlink_rcv_skb+0x137/0x3a0 > > [ +0.000012] genl_rcv+0x29/0x40 > > [ +0.000013] netlink_unicast+0x49b/0x660 > > [ +0.000013] netlink_sendmsg+0x755/0xc90 > > [ +0.000013] __sys_sendto+0x3de/0x430 > > [ +0.000013] __x64_sys_sendto+0xe2/0x1b0 > > [ +0.000013] do_syscall_64+0xa4/0x4d0 > > [ +0.000013] entry_SYSCALL_64_after_hwframe+0x49/0xbe > > > > [ +0.000017] The buggy address belongs to the object at > > ffff8881e48e0008 > > which belongs to the cache kmalloc-2k of size 2048 > > [ +0.000012] The buggy address is located 1096 bytes inside of > > 2048-byte region [ffff8881e48e0008, > > ffff8881e48e0808) > > [ +0.000007] The buggy address belongs to the page: > > [ +0.000012] page:ffffea0007923800 refcount:1 mapcount:0 > > mapping:ffff88823680d0c0 index:0x0 compound_mapcount: 0 > > [ +0.000020] flags: 0x200000000010200(slab|head) > > [ +0.000019] raw: 0200000000010200 ffffea0007682008 > > ffffea00076ab808 ffff88823680d0c0 > > [ +0.000016] raw: 0000000000000000 00000000000d000d > > 00000001ffffffff 0000000000000000 > > [ +0.000007] page dumped because: kasan: bad access detected > > > > [ +0.000012] Memory state around the buggy address: > > [ +0.000012] ffff8881e48e0300: fb fb fb fb fb fb fb fb fb fb fb > > fb fb fb fb fb > > [ +0.000012] ffff8881e48e0380: fb fb fb fb fb fb fb fb fb fb fb > > fb fb fb fb fb > > [ +0.000012] >ffff8881e48e0400: fb fb fb fb fb fb fb fb fb fb fb > > fb fb fb fb fb > > [ +0.000008] ^ > > [ +0.000012] ffff8881e48e0480: fb fb fb fb fb fb fb fb fb fb fb > > fb fb fb fb fb > > [ +0.000012] ffff8881e48e0500: fb fb fb fb fb fb fb fb fb fb fb > > fb fb fb fb fb > > [ +0.000007] > > ================================================================== > > > > Fixes: b1569e99c795 ("ACPI: move thermal trip handling to generic > > thermal layer") > > Reported-by: Jiri Pirko <jiri@xxxxxxxxxxxx> > > Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxxxx> > > Acked-by: Jiri Pirko <jiri@xxxxxxxxxxxx> > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > > --- > > drivers/thermal/thermal_core.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/thermal/thermal_core.c > > b/drivers/thermal/thermal_core.c > > index 6bab66e84eb58..ebe15f2cf7fc3 100644 > > --- a/drivers/thermal/thermal_core.c > > +++ b/drivers/thermal/thermal_core.c > > @@ -304,7 +304,7 @@ static void > > thermal_zone_device_set_polling(struct thermal_zone_device *tz, > > &tz->poll_queue, > > msecs_to_jiffies(delay)); > > else > > - cancel_delayed_work(&tz->poll_queue); > > + cancel_delayed_work_sync(&tz->poll_queue); > > } > > > > static void monitor_thermal_zone(struct thermal_zone_device *tz) > >
