Commits
Lv Zheng committed 06a8566bcf5
ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()
This patch fixes the issues indicated by the test results that
ipmi_msg_handler() is invoked in atomic context.
BUG: scheduling while atomic: kipmi0/18933/0x10000100
Modules linked in: ipmi_si acpi_ipmi ...
CPU: 3 PID: 18933 Comm: kipmi0 Tainted: G AW 3.10.0-rc7+ #2
Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.0027.070120100606 07/01/2010
ffff8838245eea00 ffff88103fc63c98 ffffffff814c4a1e ffff88103fc63ca8
ffffffff814bfbab ffff88103fc63d28 ffffffff814c73e0 ffff88103933cbd4
0000000000000096 ffff88103fc63ce8 ffff88102f618000 ffff881035c01fd8
Call Trace:
<IRQ> [<ffffffff814c4a1e>] dump_stack+0x19/0x1b
[<ffffffff814bfbab>] __schedule_bug+0x46/0x54
[<ffffffff814c73e0>] __schedule+0x83/0x59c
[<ffffffff81058853>] __cond_resched+0x22/0x2d
[<ffffffff814c794b>] _cond_resched+0x14/0x1d
[<ffffffff814c6d82>] mutex_lock+0x11/0x32
[<ffffffff8101e1e9>] ? __default_send_IPI_dest_field.constprop.0+0x53/0x58
[<ffffffffa09e3f9c>] ipmi_msg_handler+0x23/0x166 [ipmi_si]
[<ffffffff812bf6e4>] deliver_response+0x55/0x5a
[<ffffffff812c0fd4>] handle_new_recv_msgs+0xb67/0xc65
[<ffffffff81007ad1>] ? read_tsc+0x9/0x19
[<ffffffff814c8620>] ? _raw_spin_lock_irq+0xa/0xc
[<ffffffffa09e1128>] ipmi_thread+0x5c/0x146 [ipmi_si]
...
Also Tony Camuso says:
We were getting occasional "Scheduling while atomic" call traces
during boot on some systems. Problem was first seen on a Cisco C210
but we were able to reproduce it on a Cisco c220m3. Setting
CONFIG_LOCKDEP and LOCKDEP_SUPPORT to 'y' exposed a lockdep around
tx_msg_lock in acpi_ipmi.c struct acpi_ipmi_device.
=================================
[ INFO: inconsistent lock state ]
2.6.32-415.el6.x86_64-debug-splck #1
---------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
ksoftirqd/3/17 [HC0[0]:SC1[1]:HE1:SE0] takes:
(&ipmi_device->tx_msg_lock){+.?...}, at: [<ffffffff81337a27>] ipmi_msg_handler+0x71/0x126
{SOFTIRQ-ON-W} state was registered at:
[<ffffffff810ba11c>] __lock_acquire+0x63c/0x1570
[<ffffffff810bb0f4>] lock_acquire+0xa4/0x120
[<ffffffff815581cc>] __mutex_lock_common+0x4c/0x400
[<ffffffff815586ea>] mutex_lock_nested+0x4a/0x60
[<ffffffff8133789d>] acpi_ipmi_space_handler+0x11b/0x234
[<ffffffff81321c62>] acpi_ev_address_space_dispatch+0x170/0x1be
The fix implemented by this change has been tested by Tony:
Tested the patch in a boot loop with lockdep debug enabled and never
saw the problem in over 400 reboots.
Reported-and-tested-by: Tony Camuso <tcamuso@redhat.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>