# git rev-parse -q --verify 21f8b2fa3ca5b01f7a2b51b89ce97a3705a15aa0^{commit}
21f8b2fa3ca5b01f7a2b51b89ce97a3705a15aa0
already have revision, skipping fetch
# git checkout -q -f -B kisskb 21f8b2fa3ca5b01f7a2b51b89ce97a3705a15aa0
# git clean -qxdf
# < git log -1
# commit 21f8b2fa3ca5b01f7a2b51b89ce97a3705a15aa0
# Author: Christophe Leroy <christophe.leroy@c-s.fr>
# Date:   Tue Feb 18 19:38:27 2020 +0000
# 
#     powerpc/kprobes: Ignore traps that happened in real mode
#     
#     When a program check exception happens while MMU translation is
#     disabled, following Oops happens in kprobe_handler() in the following
#     code:
#     
#             } else if (*addr != BREAKPOINT_INSTRUCTION) {
#     
#       BUG: Unable to handle kernel data access on read at 0x0000e268
#       Faulting instruction address: 0xc000ec34
#       Oops: Kernel access of bad area, sig: 11 [#1]
#       BE PAGE_SIZE=16K PREEMPT CMPC885
#       Modules linked in:
#       CPU: 0 PID: 429 Comm: cat Not tainted 5.6.0-rc1-s3k-dev-00824-g84195dc6c58a #3267
#       NIP:  c000ec34 LR: c000ecd8 CTR: c019cab8
#       REGS: ca4d3b58 TRAP: 0300   Not tainted  (5.6.0-rc1-s3k-dev-00824-g84195dc6c58a)
#       MSR:  00001032 <ME,IR,DR,RI>  CR: 2a4d3c52  XER: 00000000
#       DAR: 0000e268 DSISR: c0000000
#       GPR00: c000b09c ca4d3c10 c66d0620 00000000 ca4d3c60 00000000 00009032 00000000
#       GPR08: 00020000 00000000 c087de44 c000afe0 c66d0ad0 100d3dd6 fffffff3 00000000
#       GPR16: 00000000 00000041 00000000 ca4d3d70 00000000 00000000 0000416d 00000000
#       GPR24: 00000004 c53b6128 00000000 0000e268 00000000 c07c0000 c07bb6fc ca4d3c60
#       NIP [c000ec34] kprobe_handler+0x128/0x290
#       LR [c000ecd8] kprobe_handler+0x1cc/0x290
#       Call Trace:
#       [ca4d3c30] [c000b09c] program_check_exception+0xbc/0x6fc
#       [ca4d3c50] [c000e43c] ret_from_except_full+0x0/0x4
#       --- interrupt: 700 at 0xe268
#       Instruction dump:
#       913e0008 81220000 38600001 3929ffff 91220000 80010024 bb410008 7c0803a6
#       38210020 4e800020 38600000 4e800020 <813b0000> 6d2a7fe0 2f8a0008 419e0154
#       ---[ end trace 5b9152d4cdadd06d ]---
#     
#     kprobe is not prepared to handle events in real mode and functions
#     running in real mode should have been blacklisted, so kprobe_handler()
#     can safely bail out telling 'this trap is not mine' for any trap that
#     happened while in real-mode.
#     
#     If the trap happened with MSR_IR or MSR_DR cleared, return 0
#     immediately.
#     
#     Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
#     Fixes: 6cc89bad60a6 ("powerpc/kprobes: Invoke handlers directly")
#     Cc: stable@vger.kernel.org # v4.10+
#     Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
#     Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
#     Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://lore.kernel.org/r/424331e2006e7291a1bfe40e7f3fa58825f565e1.1582054578.git.christophe.leroy@c-s.fr
# < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-ld --version
# < git log --format=%s --max-count=1 21f8b2fa3ca5b01f7a2b51b89ce97a3705a15aa0
# < make -s -j 24 ARCH=ia64 O=/kisskb/build/powerpc-next_ia64-defconfig_ia64-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-  defconfig
# < make -s -j 24 ARCH=ia64 O=/kisskb/build/powerpc-next_ia64-defconfig_ia64-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-  help
# make -s -j 24 ARCH=ia64 O=/kisskb/build/powerpc-next_ia64-defconfig_ia64-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-  olddefconfig
# make -s -j 24 ARCH=ia64 O=/kisskb/build/powerpc-next_ia64-defconfig_ia64-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/ia64-linux/bin/ia64-linux-  
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]
In file included from /kisskb/src/arch/ia64/include/uapi/asm/intrinsics.h:22:0,
                 from /kisskb/src/arch/ia64/include/asm/intrinsics.h:11,
                 from /kisskb/src/arch/ia64/include/asm/bitops.h:19,
                 from /kisskb/src/include/linux/bitops.h:29,
                 from /kisskb/src/include/linux/kernel.h:12,
                 from /kisskb/src/include/linux/list.h:9,
                 from /kisskb/src/include/linux/preempt.h:11,
                 from /kisskb/src/include/linux/spinlock.h:51,
                 from /kisskb/src/include/linux/seqlock.h:36,
                 from /kisskb/src/include/linux/time.h:6,
                 from /kisskb/src/fs/nfs/read.c:11:
/kisskb/src/fs/nfs/read.c: In function 'nfs_read_completion':
/kisskb/src/arch/ia64/include/uapi/asm/cmpxchg.h:57:2: warning: value computed is not used [-Wunused-value]
 ((__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr))))
  ^
/kisskb/src/fs/nfs/read.c:196:5: note: in expansion of macro 'xchg'
     xchg(&nfs_req_openctx(req)->error, error);
     ^
/kisskb/src/fs/nfs/read.c: In function 'nfs_readpage':
/kisskb/src/arch/ia64/include/uapi/asm/cmpxchg.h:57:2: warning: value computed is not used [-Wunused-value]
 ((__typeof__(*(ptr))) __xchg((unsigned long) (x), (ptr), sizeof(*(ptr))))
  ^
/kisskb/src/fs/nfs/read.c:353:2: note: in expansion of macro 'xchg'
  xchg(&ctx->error, 0);
  ^
/kisskb/src/drivers/gpu/drm/drm_dp_mst_topology.c: In function 'drm_dp_mst_dsc_aux_for_port':
/kisskb/src/drivers/gpu/drm/drm_dp_mst_topology.c:5400:9: warning: missing braces around initializer [-Wmissing-braces]
  struct drm_dp_desc desc = { 0 };
         ^
/kisskb/src/drivers/gpu/drm/drm_dp_mst_topology.c:5400:9: warning: (near initialization for 'desc.ident') [-Wmissing-braces]
No errors detected in 21897 functions.
Completed OK
# rm -rf /kisskb/build/powerpc-next_ia64-defconfig_ia64-gcc4.9
# Build took: 0:02:44.510929