linux_dsm_epyc7002/drivers
Masamitsu Yamazaki 4f7f5551a7 ipmi: Stop timers before cleaning up the module
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
 --- <NMI exception stack> ---

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: 0cfec916e8 ("ipmi: Start the timer and thread on internal msgs")
Signed-off-by: Yamazaki Masamitsu <m-yamazaki@ah.jp.nec.com>
[Adjusted for recent changes in the driver.]
Signed-off-by: Corey Minyard <cminyard@mvista.com>
2017-12-06 07:13:03 -06:00
..
accessibility License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
acpi Modules updates for v4.15 2017-11-15 13:46:33 -08:00
amba A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
android Modules updates for v4.15 2017-11-15 13:46:33 -08:00
ata Merge branch 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2017-11-15 14:11:41 -08:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
auxdisplay Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
base DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
bcma Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
block A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
bus arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
cdrom Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
char ipmi: Stop timers before cleaning up the module 2017-12-06 07:13:03 -06:00
clk One fix for USB clks on Uniphier PXs3 SoCs 2017-11-03 13:56:15 -07:00
clocksource arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
connector
cpufreq Power management updates for v4.15-rc1 2017-11-13 19:43:50 -08:00
cpuidle Merge branch 'pm-cpuidle' 2017-11-13 01:34:14 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-14 10:52:09 -08:00
dax License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dca
devfreq Merge branches 'pm-devfreq' and 'pm-tools' 2017-11-13 01:41:39 +01:00
dio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dma dmaengine updates for 4.15-rc1 2017-11-14 16:49:31 -08:00
dma-buf License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
edac Modules updates for v4.15 2017-11-15 13:46:33 -08:00
eisa License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extcon USB/PHY patches for 4.15-rc1 2017-11-13 21:14:07 -08:00
firewire Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
firmware Merge branch 'linus' into locking/core, to resolve conflicts 2017-11-07 10:32:44 +01:00
fmc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fpga License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fsi
gpio Merge branch 'i2c/for-4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2017-11-14 17:52:21 -08:00
gpu DeviceTree for 4.15: 2017-11-14 18:25:40 -08:00
hid Modules updates for v4.15 2017-11-15 13:46:33 -08:00
hsi HSI changes for the v4.15 series 2017-11-15 13:35:43 -08:00
hv x86/virt: Add enum for hypervisors to replace x86_hyper 2017-11-10 10:03:12 +01:00
hwmon hwmon updates for v4.15 2017-11-13 08:55:46 -08:00
hwspinlock License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hwtracing A couple of configfs cleanups: 2017-11-14 14:44:04 -08:00
i2c Merge branch 'i2c/for-4.15' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2017-11-14 17:52:21 -08:00
ide Modules updates for v4.15 2017-11-15 13:46:33 -08:00
idle Merge branch 'pm-cpuidle' 2017-11-13 01:34:14 +01:00
iio A couple of configfs cleanups: 2017-11-14 14:44:04 -08:00
infiniband Updates for 4.15 kernel merge window 2017-11-15 14:54:53 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2017-11-14 18:07:18 -08:00
iommu IOMMU Updates for Linux v4.15 2017-11-14 16:43:27 -08:00
ipack
irqchip pci-v4.15-changes 2017-11-15 15:01:28 -08:00
isdn Modules updates for v4.15 2017-11-15 13:46:33 -08:00
leds LED updates for 4.15rc1 2017-11-14 18:09:31 -08:00
lightnvm Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
macintosh Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
mailbox Change to POLL api and fixes for FlexRM and OMAP driver 2017-11-15 13:39:18 -08:00
mcb License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
md Modules updates for v4.15 2017-11-15 13:46:33 -08:00
media Modules updates for v4.15 2017-11-15 13:46:33 -08:00
memory License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
memstick Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
message Modules updates for v4.15 2017-11-15 13:46:33 -08:00
mfd sound updates for 4.15-rc1 2017-11-14 18:01:46 -08:00
misc pci-v4.15-changes 2017-11-15 15:01:28 -08:00
mmc MMC core: 2017-11-13 10:17:35 -08:00
mtd Modules updates for v4.15 2017-11-15 13:46:33 -08:00
mux
net Updates for 4.15 kernel merge window 2017-11-15 14:54:53 -08:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
ntb
nubus m68k updates for 4.15 2017-11-13 12:10:24 -08:00
nvdimm Merge branch 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2017-11-15 10:14:11 -08:00
nvme Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
nvmem License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
of pci-v4.15-changes 2017-11-15 15:01:28 -08:00
opp
oprofile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
parisc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
parport Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
pci pci-v4.15-changes 2017-11-15 15:01:28 -08:00
pcmcia pci-v4.15-changes 2017-11-15 15:01:28 -08:00
perf arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
phy USB/PHY patches for 4.15-rc1 2017-11-13 21:14:07 -08:00
pinctrl This is the bulk of GPIO changes for the v4.15 kernel cycle: 2017-11-14 17:23:44 -08:00
platform Modules updates for v4.15 2017-11-15 13:46:33 -08:00
pnp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
power power supply and reset changes for the v4.15 series 2017-11-15 13:37:15 -08:00
powercap
pps
ps3
ptp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pwm License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rapidio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ras Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
regulator MMC core: 2017-11-13 10:17:35 -08:00
remoteproc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
reset License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rpmsg License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rtc Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
sbus License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
scsi Modules updates for v4.15 2017-11-15 13:46:33 -08:00
sfi
sh A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
sn
soc USB/PHY patches for 4.15-rc1 2017-11-13 21:14:07 -08:00
spi Merge remote-tracking branches 'spi/topic/sh-msiof', 'spi/topic/slave', 'spi/topic/spreadtrum' and 'spi/topic/tegra114' into spi-next 2017-11-10 21:33:51 +00:00
spmi
ssb License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
staging Updates for 4.15 kernel merge window 2017-11-15 14:54:53 -08:00
target A couple of configfs cleanups: 2017-11-14 14:44:04 -08:00
tc
tee License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
thermal License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
thunderbolt Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
tty Modules updates for v4.15 2017-11-15 13:46:33 -08:00
uio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
usb sound updates for 4.15-rc1 2017-11-14 18:01:46 -08:00
uwb License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vfio VFIO Updates for Linux v4.15 2017-11-14 16:47:47 -08:00
vhost Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
video License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
virt
virtio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vlynq
vme License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
w1 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
watchdog MIPS changes for 4.15 2017-11-15 11:36:08 -08:00
xen Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
zorro License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig Merge branches 'pm-cpufreq-sched' and 'pm-opp' 2017-11-13 01:40:52 +01:00
Makefile Merge branches 'pm-cpufreq-sched' and 'pm-opp' 2017-11-13 01:40:52 +01:00