kernel/linux.git/drivers/char/ipmi, branch v4.4.171

ipmi: Fix timer race with module unload

2018-11-21T08:27:30+00:00

commit 0711e8c1b4572d076264e71b0002d223f2666ed7 upstream. Please note that below oops is from an older kernel, but the same race seems to be present in the upstream kernel too. ---8<--- The following panic was encountered during removing the ipmi_ssif module: [ 526.352555] Unable to handle kernel paging request at virtual address ffff000006923090 [ 526.360464] Mem abort info: [ 526.363257] ESR = 0x86000007 [ 526.366304] Exception class = IABT (current EL), IL = 32 bits [ 526.372221] SET = 0, FnV = 0 [ 526.375269] EA = 0, S1PTW = 0 [ 526.378405] swapper pgtable: 4k pages, 48-bit VAs, pgd = 000000008ae60416 [ 526.385185] [ffff000006923090] *pgd=000000bffcffe803, *pud=000000bffcffd803, *pmd=0000009f4731a003, *pte=0000000000000000 [ 526.396141] Internal error: Oops: 86000007 [#1] SMP [ 526.401008] Modules linked in: nls_iso8859_1 ipmi_devintf joydev input_leds ipmi_msghandler shpchp sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear i2c_smbus hid_generic usbhid uas hid usb_storage ast aes_ce_blk i2c_algo_bit aes_ce_cipher qede ttm crc32_ce ptp crct10dif_ce drm_kms_helper ghash_ce syscopyarea sha2_ce sysfillrect sysimgblt pps_core fb_sys_fops sha256_arm64 sha1_ce mpt3sas qed drm raid_class ahci scsi_transport_sas libahci gpio_xlp i2c_xlp9xx aes_neon_bs aes_neon_blk crypto_simd cryptd aes_arm64 [last unloaded: ipmi_ssif] [ 526.468085] CPU: 125 PID: 0 Comm: swapper/125 Not tainted 4.15.0-35-generic #38~lp1775396+build.1 [ 526.476942] Hardware name: To be filled by O.E.M. Saber/Saber, BIOS 0ACKL022 08/14/2018 [ 526.484932] pstate: 00400009 (nzcv daif +PAN -UAO) [ 526.489713] pc : 0xffff000006923090 [ 526.493198] lr : call_timer_fn+0x34/0x178 [ 526.497194] sp : ffff000009b0bdd0 [ 526.500496] x29: ffff000009b0bdd0 x28: 0000000000000082 [ 526.505796] x27: 0000000000000002 x26: ffff000009515188 [ 526.511096] x25: ffff000009515180 x24: ffff0000090f1018 [ 526.516396] x23: ffff000009519660 x22: dead000000000200 [ 526.521696] x21: ffff000006923090 x20: 0000000000000100 [ 526.526995] x19: ffff809eeb466a40 x18: 0000000000000000 [ 526.532295] x17: 000000000000000e x16: 0000000000000007 [ 526.537594] x15: 0000000000000000 x14: 071c71c71c71c71c [ 526.542894] x13: 0000000000000000 x12: 0000000000000000 [ 526.548193] x11: 0000000000000001 x10: ffff000009b0be88 [ 526.553493] x9 : 0000000000000000 x8 : 0000000000000005 [ 526.558793] x7 : ffff80befc1f8528 x6 : 0000000000000020 [ 526.564092] x5 : 0000000000000040 x4 : 0000000020001b20 [ 526.569392] x3 : 0000000000000000 x2 : ffff809eeb466a40 [ 526.574692] x1 : ffff000006923090 x0 : ffff809eeb466a40 [ 526.579992] Process swapper/125 (pid: 0, stack limit = 0x000000002eb50acc) [ 526.586854] Call trace: [ 526.589289] 0xffff000006923090 [ 526.592419] expire_timers+0xc8/0x130 [ 526.596070] run_timer_softirq+0xec/0x1b0 [ 526.600070] __do_softirq+0x134/0x328 [ 526.603726] irq_exit+0xc8/0xe0 [ 526.606857] __handle_domain_irq+0x6c/0xc0 [ 526.610941] gic_handle_irq+0x84/0x188 [ 526.614679] el1_irq+0xe8/0x180 [ 526.617822] cpuidle_enter_state+0xa0/0x328 [ 526.621993] cpuidle_enter+0x34/0x48 [ 526.625564] call_cpuidle+0x44/0x70 [ 526.629040] do_idle+0x1b8/0x1f0 [ 526.632256] cpu_startup_entry+0x2c/0x30 [ 526.636174] secondary_start_kernel+0x11c/0x130 [ 526.640694] Code: bad PC value [ 526.643800] ---[ end trace d020b0b8417c2498 ]--- [ 526.648404] Kernel panic - not syncing: Fatal exception in interrupt [ 526.654778] SMP: stopping secondary CPUs [ 526.658734] Kernel Offset: disabled [ 526.662211] CPU features: 0x5800c38 [ 526.665688] Memory Limit: none [ 526.668768] ---[ end Kernel panic - not syncing: Fatal exception in interrupt Prevent mod_timer from arming a timer that was already removed by del_timer during module unload. Signed-off-by: Jan Glauber Cc: # 3.19 Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:bt: Set the timeout before doing a capabilities check

2018-07-03T09:21:28+00:00

commit fe50a7d0393a552e4539da2d31261a59d6415950 upstream. There was one place where the timeout value for an operation was not being set, if a capabilities request was done from idle. Move the timeout value setting to before where that change might be requested. IMHO the cause here is the invisible returns in the macros. Maybe that's a job for later, though. Reported-by: Nordmark Claes Signed-off-by: Corey Minyard Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

ipmi_ssif: Fix kernel panic at msg_done_handler

2018-05-30T05:49:12+00:00

[ Upstream commit f002612b9d86613bc6fde0a444e0095225f6053e ] This happens when BMC doesn't return any data and the code is trying to print the value of data[2]. Getting following crash: [ 484.728410] Unable to handle kernel NULL pointer dereference at virtual address 00000002 [ 484.736496] pgd = ffff0000094a2000 [ 484.739885] [00000002] *pgd=00000047fcffe003, *pud=00000047fcffd003, *pmd=0000000000000000 [ 484.748158] Internal error: Oops: 96000005 [#1] SMP [...] [ 485.101451] Call trace: [...] [ 485.188473] [] msg_done_handler+0x668/0x700 [ipmi_ssif] [ 485.195249] [] ipmi_ssif_thread+0x110/0x128 [ipmi_ssif] [ 485.202038] [] kthread+0x108/0x138 [ 485.206994] [] ret_from_fork+0x10/0x30 [ 485.212294] Code: aa1903e1 aa1803e0 b900227f 95fef6a5 (39400aa3) Adding a check to validate the data len before printing data[2] to fix this issue. Signed-off-by: Kamlakant Patel Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipmi/powernv: Fix error return code in ipmi_powernv_probe()

2018-05-30T05:48:54+00:00

[ Upstream commit e749d328b0b450aa78d562fa26a0cd8872325dd9 ] Fix to return a negative error code from the request_irq() error handling case instead of 0, as done elsewhere in this function. Fixes: dce143c3381c ("ipmi/powernv: Convert to irq event interface") Signed-off-by: Wei Yongjun Reviewed-by: Alexey Kardashevskiy Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipmi_ssif: unlock on allocation failure

2018-04-13T17:50:02+00:00

[ Upstream commit cf9806f32ef63b745f2486e0dbb2ac21f4ca44f0 ] We should unlock and re-enable IRQs if this allocation fails. Fixes: 259307074bfc ("ipmi: Add SMBus interface driver (SSIF) ") Signed-off-by: Dan Carpenter Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipmi/watchdog: fix wdog hang on panic waiting for ipmi response

2018-03-24T09:58:45+00:00

[ Upstream commit 2c1175c2e8e5487233cabde358a19577562ac83e ] Commit c49c097610fe ("ipmi: Don't call receive handler in the panic context") means that the panic_recv_free is not called during a panic and the atomic count does not drop to 0. Fix this by only expecting one decrement of the atomic variable which comes from panic_smi_free. Signed-off-by: Robert Lippert Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipmi: Stop timers before cleaning up the module

2017-12-16T09:33:56+00:00

commit 4f7f5551a760eb0124267be65763008169db7087 upstream. System may crash after unloading ipmi_si.ko module because a timer may remain and fire after the module cleaned up resources. cleanup_one_si() contains the following processing. /* * Make sure that interrupts, the timer and the thread are * stopped and will not run again. */ if (to_clean->irq_cleanup) to_clean->irq_cleanup(to_clean); wait_for_timer_and_thread(to_clean); /* * Timeouts are stopped, now make sure the interrupts are off * in the BMC. Note that timers and CPU interrupts are off, * so no need for locks. */ while (to_clean->curr_msg || (to_clean->si_state != SI_NORMAL)) { poll(to_clean); schedule_timeout_uninterruptible(1); } si_state changes as following in the while loop calling poll(to_clean). SI_GETTING_MESSAGES => SI_CHECKING_ENABLES => SI_SETTING_ENABLES => SI_GETTING_EVENTS => SI_NORMAL As written in the code comments above, timers are expected to stop before the polling loop and not to run again. But the timer is set again in the following process when si_state becomes SI_SETTING_ENABLES. => poll => smi_event_handler => handle_transaction_done // smi_info->si_state == SI_SETTING_ENABLES => start_getting_events => start_new_msg => smi_mod_timer => mod_timer As a result, before the timer set in start_new_msg() expires, the polling loop may see si_state becoming SI_NORMAL and the module clean-up finishes. For example, hard LOCKUP and panic occurred as following. smi_timeout was called after smi_event_handler, kcs_event and hangs at port_inb() trying to access I/O port after release. [exception RIP: port_inb+19] RIP: ffffffffc0473053 RSP: ffff88069fdc3d80 RFLAGS: 00000006 RAX: ffff8806800f8e00 RBX: ffff880682bd9400 RCX: 0000000000000000 RDX: 0000000000000ca3 RSI: 0000000000000ca3 RDI: ffff8806800f8e40 RBP: ffff88069fdc3d80 R8: ffffffff81d86dfc R9: ffffffff81e36426 R10: 00000000000509f0 R11: 0000000000100000 R12: 0000000000]:000000 R13: 0000000000000000 R14: 0000000000000246 R15: ffff8806800f8e00 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 --- --- To fix the problem I defined a flag, timer_can_start, as member of struct smi_info. The flag is enabled immediately after initializing the timer and disabled immediately before waiting for timer deletion. Fixes: 0cfec916e86d ("ipmi: Start the timer and thread on internal msgs") Signed-off-by: Yamazaki Masamitsu [Adjusted for recent changes in the driver.] [Some fairly major changes went into the IPMI driver in 4.15, so this required a backport as the code had changed and moved to a different file. The 4.14 version of this patch moved some code under an if statement and there was an API change causing it to not apply to 4.4-4.6.] Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: fix unsigned long underflow

2017-11-24T07:32:25+00:00

commit 392a17b10ec4320d3c0e96e2a23ebaad1123b989 upstream. When I set the timeout to a specific value such as 500ms, the timeout event will not happen in time due to the overflow in function check_msg_timeout: ... ent->timeout -= timeout_period; if (ent->timeout > 0) return; ... The type of timeout_period is long, but ent->timeout is unsigned long. This patch makes the type consistent. Reported-by: Weilong Chen Signed-off-by: Corey Minyard Tested-by: Weilong Chen Signed-off-by: Greg Kroah-Hartman

ipmi/watchdog: fix watchdog timeout set on reboot

2017-08-07T02:19:42+00:00

commit 860f01e96981a68553f3ca49f574ff14fe955e72 upstream. systemd by default starts watchdog on reboot and sets the timer to ShutdownWatchdogSec=10min. Reboot handler in ipmi_watchdog than reduces the timer to 120s which is not enough time to boot a Xen machine with a lot of RAM. As a result the machine is rebooted the second time during the long run of (XEN) Scrubbing Free RAM..... Fix this by setting the timer to 120s only if it was previously set to a low value. Signed-off-by: Valentin Vidic Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Add missing unlock in error branch

2017-07-27T22:06:06+00:00

commit 4495ec6d770e1bca7a04e93ac453ab6720c56c5d upstream. When getting flags, a response to a different message would result in a deadlock because of a missing unlock. Add that unlock and a comment. Found by static analysis. Reported-by: Dan Carpenter Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman