Lorenzo Bianconi <lorenzo@xxxxxxxxxx> wrote:
> Fix the following crash due to erroneous page refcounting:
>
> [ 32.445919] BUG: Bad page state in process swapper/1 pfn:11f65a
> [ 32.447409] page:00000000938f0632 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x0 pfn:0x11f65a
> [ 32.449605] flags: 0x8000000000000000()
> [ 32.450421] raw: 8000000000000000 ffffffff825b0148 ffffea00045ae988 0000000000000000
> [ 32.451795] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000
> [ 32.452999] page dumped because: nonzero mapcount
> [ 32.453888] Modules linked in:
> [ 32.454492] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.11.0-rc2+ #1976
> [ 32.455695] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-1.fc33 04/01/2014
> [ 32.457157] Call Trace:
> [ 32.457636] <IRQ>
> [ 32.457993] dump_stack+0x77/0x97
> [ 32.458576] bad_page.cold+0x65/0x96
> [ 32.459198] get_page_from_freelist+0x46a/0x11f0
> [ 32.460008] __alloc_pages_nodemask+0x10a/0x2b0
> [ 32.460794] mt7601u_rx_tasklet+0x651/0x720
> [ 32.461505] tasklet_action_common.constprop.0+0x6b/0xd0
> [ 32.462343] __do_softirq+0x152/0x46c
> [ 32.462928] asm_call_irq_on_stack+0x12/0x20
> [ 32.463610] </IRQ>
> [ 32.463953] do_softirq_own_stack+0x5b/0x70
> [ 32.464582] irq_exit_rcu+0x9f/0xe0
> [ 32.465028] common_interrupt+0xae/0x1a0
> [ 32.465536] asm_common_interrupt+0x1e/0x40
> [ 32.466071] RIP: 0010:default_idle+0x18/0x20
> [ 32.468981] RSP: 0018:ffffc90000077f00 EFLAGS: 00000246
> [ 32.469648] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
> [ 32.470550] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff81aac3dd
> [ 32.471463] RBP: ffff88810022ab00 R08: 0000000000000001 R09: 0000000000000001
> [ 32.472335] R10: 0000000000000046 R11: 0000000000005aa0 R12: 0000000000000000
> [ 32.473235] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> [ 32.474139] ? default_idle_call+0x4d/0x200
> [ 32.474681] default_idle_call+0x74/0x200
> [ 32.475192] do_idle+0x1d5/0x250
> [ 32.475612] cpu_startup_entry+0x19/0x20
> [ 32.476114] secondary_startup_64_no_verify+0xb0/0xbb
> [ 32.476765] Disabling lock debugging due to kernel taint
>
> Fixes: c869f77d6abb ("add mt7601u driver")
> Co-developed-by: Felix Fietkau <nbd@xxxxxxxx>
> Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
> Acked-by: Jakub Kicinski <kubakici@xxxxx>
Patch applied to wireless-drivers.git, thanks.
d24c790577ef mt7601u: fix rx buffer refcounting
--
https://patchwork.kernel.org/project/linux-wireless/patch/62b2380c8c2091834cfad05e1059b55f945bd114.1610643952.git.lorenzo@xxxxxxxxxx/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
