On Sun, 2013-05-19 at 22:12 -0700, Lisa Du wrote: > Dear Sir > Recently I met a deadlock case which is caused by proc_subdir_lock used in softirq context. > So I searched the mailing list and find there’s already the discussion in 2006 as below: > http://lkml.indiana.edu/hypermail/linux/kernel/0601.3/0437.html > And I also checked the mainline, seems no direct fix patch for this potential issue. > So I want to know if there’s any concern that mainline didn’t accept the patch? I believe the real fix is not to call remove or create proc from softirq context. What kernel are you using, as I can't find uid_stat_tcp_rcv() anywhere in the latest kernel. -- Steve > Looking forward to your reply and thanks in advance! > > BTW: below are the soft lockup panic stack I have got: > #0 [<c0181b98>] (crash_update) from [<c0135980>] > #1 [<c0135980>] (panic_flush) from [<c015b454>] > #2 [<c015b454>] (notifier_call_chain) from [<c015b618>] > #3 [<c015b618>] (__atomic_notifier_call_chain) from [<c015b63c>] > #4 [<c015b63c>] (atomic_notifier_call_chain) from [<c05c323c>] > #5 [<c05c323c>] (panic) from [<c0183278>] > #6 [<c0183278>] (watchdog_timer_fn) from [<c01598c8>] > #7 [<c01598c8>] (__run_hrtimer) from [<c015a4fc>] > #8 [<c015a4fc>] (hrtimer_interrupt) from [<c01183c0>] > #9 [<c01183c0>] (twd_handler) from [<c0186c60>] > #10 [<c0186c60>] (handle_percpu_devid_irq) from [<c0183894>] > #11 [<c0183894>] (generic_handle_irq) from [<c0113c9c>] > #12 [<c0113c9c>] (handle_IRQ) from [<c01084ac>] > #13 [<c01084ac>] (gic_handle_irq) from [<c0112980>] > pc : [<c05c9e90>] lr : [<c05c9e68>] psr: 20000113 > sp : dc831780 ip : 00000000 fp : 000003d8 > r10: c4180ad0 r9 : c05757dc r8 : dc831828 > r7 : 00000002 r6 : 00000001 r5 : dc830000 r4 : c08b7294 > r3 : 00000001 r2 : dc831770 r1 : 00000000 r0 : 00000001 > Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM > #14 [<c0112980>] (__irq_svc) from [<c05c9e68>] > #15 [<c05c9e90>] (__raw_spin_lock) from [<c021ef7c>] > #16 [<c021ef7c>] (__proc_create) from [<c021f1b8>] > #17 [<c021f1b8>] (proc_mkdir_mode) from [<c034fcc4>] > #18 [<c034fcc4>] (create_stat) from [<c034fdb4>] > #19 [<c034fdb4>] (uid_stat_tcp_rcv) from [<c04bf498>] > #20 [<c04bf498>] (tcp_read_sock) from [<c0575478>] > #21 [<c0575478>] (xs_tcp_data_ready) from [<c04c7c48>] > #22 [<c04c7c48>] (tcp_rcv_established) from [<c04cdba4>] > #23 [<c04cdba4>] (tcp_v4_do_rcv) from [<c04cfb24>] > #24 [<c04cfb24>] (tcp_v4_rcv) from [<c04b0ac8>] > #25 [<c04b0ac8>] (ip_local_deliver_finish) from [<c04b0940>] > #26 [<c04b0940>] (ip_rcv_finish) from [<c0479974>] > #27 [<c0479974>] (__netif_receive_skb) from [<c0479b5c>] > #28 [<c0479b5c>] (process_backlog) from [<c047ccc8>] > #29 [<c047ccc8>] (net_rx_action) from [<c013f9b8>] > #30 [<c013f9b8>] (__do_softirq) from [<c013ff00>] > #31 [<c013ff00>] (irq_exit) from [<c0113ca0>] > #32 [<c0113ca0>] (handle_IRQ) from [<c01084ac>] > #33 [<c01084ac>] (gic_handle_irq) from [<c0112980>] > pc : [<c02e7294>] lr : [<c021ee08>] psr: 20000113 > sp : dc831a48 ip : 005f7000 fp : 00000000 > r10: c8145e74 r9 : 60000113 r8 : 60000113 > r7 : d216c8d5 r6 : c8171180 r5 : c8170f00 r4 : d216c880 > r3 : 00000073 r2 : 00000067 r1 : d216c8d6 r0 : c81711d6 > Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM > #34 [<c0112980>] (__irq_svc) from [<c021ee08>] > #35 [<c02e7294>] (strcmp) from [<c021ee08>] > #36 [<c021ee08>] (proc_register) from [<c021f1cc>] > #37 [<c021f1cc>] (proc_mkdir_mode) from [<c0188540>] > #38 [<c0188540>] (register_handler_proc) from [<c01853b8>] > #39 [<c01853b8>] (__setup_irq) from [<c0185530>] > #40 [<c0185530>] (request_threaded_irq) from [<bf000388>] > #41 [<bf000388>] (gckGALDEVICE_Setup_ISR [galcore]) from [<bf0334a0>] > #42 [<bf0334a0>] (gckHARDWARE_SetPowerManagementState [galcore]) from [<bf00f840>] > #43 [<bf00f840>] (gckOS_Broadcast [galcore]) from [<bf019988>] > #44 [<bf019988>] (gckCOMMAND_EnterCommit [galcore]) from [<bf01a52c>] > #45 [<bf01a52c>] (gckCOMMAND_Commit [galcore]) from [<bf017518>] > #46 [<bf017518>] (gckKERNEL_Dispatch [galcore]) from [<bf002190>] > #47 [<bf002190>] (drv_ioctl [galcore]) from [<c01e5c84>] > #48 [<c01e5c84>] (do_vfs_ioctl) from [<c01e5d2c>] > #49 [<c01e5d2c>] (sys_ioctl) from [<c0112d80>] > > Thanks! > > Best Regards > Lisa Du > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
