• Lorenzo Bianconi's avatar
    mt76: usb: make rx page_frag_cache access atomic · 481bb043
    Lorenzo Bianconi authored
    Add rx_page_lock spinlock in order to make rx page fragment access
    atomic. This patch fixes the following crash that occasionally
    occurs during module loading/unloading
    
    BUG: unable to handle kernel paging request at ffff9f8322e19000
    PGD 27ba01067 P4D 27ba01067 PUD 27ddba063 PMD 263b35063 PTE 8000000262e19061
    Oops: 0003 [#1] SMP PTI
    CPU: 2 PID: 1766 Comm: systemd-udevd Not tainted 4.19.0-rc5+ #6
    Hardware name: ASUSTeK COMPUTER INC. ESC2000 G2/Z9PE-D8 WS, BIOS 0405 03/19/2012
    RIP: 0010:__memcpy+0x12/0x20
    RSP: 0018:ffffba13849b3ad8 EFLAGS: 00010246
    RAX: ffff9f8322e17004 RBX: 00000000000038f0 RCX: 000000000000031f
    RDX: 0000000000000000 RSI: ffffba13844cf058 RDI: ffff9f8322e18ffc
    RBP: 0000000000010c6c R08: 0000000000000000 R09: 0000607ec0000000
    R10: 0000000000000003 R11: 0000000000003e2e R12: ffff9f8324cd9540
    R13: 0000000000000000 R14: ffffba13849b3b30 R15: ffff9f8322e17000
    FS:  00007fadec85b880(0000) GS:ffff9f833fa80000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffff9f8322e19000 CR3: 0000000263428001 CR4: 00000000000606e0
    Call Trace:
     mt76x02u_mcu_fw_send_data+0x16c/0x270 [mt76x02_usb]
     mt76x0u_probe+0x35a/0x598 [mt76x0u]
     usb_probe_interface+0x113/0x310
     really_probe+0x1c8/0x400
     driver_probe_device+0x5c/0x130
     __driver_attach+0xec/0x110
     bus_for_each_dev+0x50/0x90
     bus_add_driver+0x1c0/0x280
     driver_register+0x5b/0xe0
     usb_register_driver+0x7c/0x140
     do_one_initcall+0x44/0x19b
     do_init_module+0x5a/0x210
     load_module+0x175c/0x1bc0
     __do_sys_finit_module+0x97/0xc0
     do_syscall_64+0x3f/0xf0
     entry_SYSCALL_64_after_hwframe+0x44/0xa9
    RIP: 0033:0x7fadeb6f1809
    RSP: 002b:00007ffe548f9f38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
    RAX: ffffffffffffffda RBX: 00007fadebdf0d89 RCX: 00007fadeb6f1809
    RDX: 0000000000000000 RSI: 00007fadebdf0d89 RDI: 0000000000000006
    RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000000000006 R11: 0000000000000246 R12: 0000560b9ef58ab0
    R13: 0000560b9ef29800 R14: 0000560b9ef59040 R15: 0000000000020000
    
    Fixes: c12128ce ("mt76: use a per rx queue page fragment cache")
    Reported-by: default avatarStanislaw Gruszka <sgruszka@redhat.com>
    Tested-by: default avatarStanislaw Gruszka <sgruszka@redhat.com>
    Signed-off-by: default avatarLorenzo Bianconi <lorenzo.bianconi@redhat.com>
    Signed-off-by: default avatarFelix Fietkau <nbd@nbd.name>
    481bb043
mt76.h 16.7 KB