# git rev-parse -q --verify fe76fc6aaf538df27708ffa3e5d549a6c8e16142^{commit}
fe76fc6aaf538df27708ffa3e5d549a6c8e16142
already have revision, skipping fetch
# git checkout -q -f -B kisskb fe76fc6aaf538df27708ffa3e5d549a6c8e16142
# git clean -qxdf
# < git log -1
# commit fe76fc6aaf538df27708ffa3e5d549a6c8e16142
# Author: Ming Lei <ming.lei@redhat.com>
# Date:   Tue Jan 15 11:59:52 2019 +0800
# 
#     sbitmap: Protect swap_lock from hardirq
#     
#     Because we may call blk_mq_get_driver_tag() directly from
#     blk_mq_dispatch_rq_list() without holding any lock, then HARDIRQ may
#     come and the above DEADLOCK is triggered.
#     
#     Commit ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq") tries to
#     fix this issue by using 'spin_lock_bh', which isn't enough because we
#     complete request from hardirq context direclty in case of multiqueue.
#     
#     Cc: Clark Williams <williams@redhat.com>
#     Fixes: ab53dcfb3e7b ("sbitmap: Protect swap_lock from hardirq")
#     Cc: Jens Axboe <axboe@kernel.dk>
#     Cc: Ming Lei <ming.lei@redhat.com>
#     Cc: Guenter Roeck <linux@roeck-us.net>
#     Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
#     Signed-off-by: Ming Lei <ming.lei@redhat.com>
#     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa64-linux/bin/hppa64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa64-linux/bin/hppa64-linux-ld --version
# < git log --format=%s --max-count=1 fe76fc6aaf538df27708ffa3e5d549a6c8e16142
# < make -s -j 40 ARCH=parisc O=/kisskb/build/linus_a500_defconfig_parisc64 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa64-linux/bin/hppa64-linux-  a500_defconfig
# make -s -j 40 ARCH=parisc O=/kisskb/build/linus_a500_defconfig_parisc64 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/hppa64-linux/bin/hppa64-linux-  
<stdin>:1336:2: warning: #warning syscall rseq not implemented [-Wcpp]
In file included from /kisskb/src/arch/parisc/include/asm/atomic.h:10,
                 from /kisskb/src/include/linux/atomic.h:7,
                 from /kisskb/src/arch/parisc/include/asm/bitops.h:13,
                 from /kisskb/src/include/linux/bitops.h:19,
                 from /kisskb/src/include/linux/kernel.h:11,
                 from /kisskb/src/include/linux/list.h:9,
                 from /kisskb/src/include/linux/module.h:9,
                 from /kisskb/src/drivers/scsi/scsi_debug.c:23:
/kisskb/src/drivers/scsi/scsi_debug.c: In function 'resp_start_stop':
/kisskb/src/arch/parisc/include/asm/cmpxchg.h:48:3: warning: value computed is not used [-Wunused-value]
  ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
/kisskb/src/arch/parisc/include/asm/atomic.h:78:30: note: in expansion of macro 'xchg'
 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
                              ^~~~
/kisskb/src/drivers/scsi/scsi_debug.c:1624:2: note: in expansion of macro 'atomic_xchg'
  atomic_xchg(&devip->stopped, stop);
  ^~~~~~~~~~~
Completed OK
# rm -rf /kisskb/build/linus_a500_defconfig_parisc64
# Build took: 0:00:42.333614