# git rev-parse -q --verify 5faa15883ebc90132b58c685316de2cd24735e90^{commit}
5faa15883ebc90132b58c685316de2cd24735e90
already have revision, skipping fetch
# git checkout -q -f -B kisskb 5faa15883ebc90132b58c685316de2cd24735e90
# git clean -qxdf
# < git log -1
# commit 5faa15883ebc90132b58c685316de2cd24735e90
# Author: Christopher M. Riedl <cmr@informatik.wtf>
# Date:   Mon Aug 12 22:13:14 2019 -0500
# 
#     powerpc/spinlocks: Fix oops in shared-processor spinlocks
#     
#     Booting w/ ppc64le_defconfig + CONFIG_PREEMPT results in the attached
#     kernel trace due to calling shared-processor spinlocks while not
#     running in an SPLPAR. Previously, the out-of-line spinlocks
#     implementations were selected based on CONFIG_PPC_SPLPAR at compile
#     time without a runtime shared-processor LPAR check.
#     
#     To fix, call the actual spinlock implementations from a set of common
#     functions, spin_yield() and rw_yield(), which check for
#     shared-processor LPAR during runtime and select the appropriate lock
#     implementation.
#     
#       BUG: Kernel NULL pointer dereference at 0x00000100
#       Faulting instruction address: 0xc000000000097f88
#       Oops: Kernel access of bad area, sig: 7 [#1]
#       LE PAGE_SIZE=64K MMU=Radix MMU=Hash PREEMPT SMP NR_CPUS=2048 NUMA PowerNV
#       Modules linked in:
#       CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.2.0-rc6-00491-g249155c20f9b #28
#       NIP:  c000000000097f88 LR: c000000000c07a88 CTR: c00000000015ca10
#       REGS: c0000000727079f0 TRAP: 0300   Not tainted  (5.2.0-rc6-00491-g249155c20f9b)
#       MSR:  9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE>  CR: 84000424  XER: 20040000
#       CFAR: c000000000c07a84 DAR: 0000000000000100 DSISR: 00080000 IRQMASK: 1
#       GPR00: c000000000c07a88 c000000072707c80 c000000001546300 c00000007be38a80
#       GPR04: c0000000726f0c00 0000000000000002 c00000007279c980 0000000000000100
#       GPR08: c000000001581b78 0000000080000001 0000000000000008 c00000007279c9b0
#       GPR12: 0000000000000000 c000000001730000 c000000000142558 0000000000000000
#       GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
#       GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
#       GPR24: c00000007be38a80 c000000000c002f4 0000000000000000 0000000000000000
#       GPR28: c000000072221a00 c0000000726c2600 c00000007be38a80 c00000007be38a80
#       NIP [c000000000097f88] __spin_yield+0x48/0xa0
#       LR [c000000000c07a88] __raw_spin_lock+0xb8/0xc0
#       Call Trace:
#       [c000000072707c80] [c000000072221a00] 0xc000000072221a00 (unreliable)
#       [c000000072707cb0] [c000000000bffb0c] __schedule+0xbc/0x850
#       [c000000072707d70] [c000000000c002f4] schedule+0x54/0x130
#       [c000000072707da0] [c0000000001427dc] kthreadd+0x28c/0x2b0
#       [c000000072707e20] [c00000000000c1cc] ret_from_kernel_thread+0x5c/0x70
#       Instruction dump:
#       4d9e0020 552a043e 210a07ff 79080fe0 0b080000 3d020004 3908b878 794a1f24
#       e8e80000 7ce7502a e8e70000 38e70100 <7ca03c2c> 70a70001 78a50020 4d820020
#       ---[ end trace 474d6b2b8fc5cb7e ]---
#     
#     Fixes: 499dcd41378e ("powerpc/64s: Allocate LPPACAs individually")
#     Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
#     Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
#     Link: https://lore.kernel.org/r/20190813031314.1828-4-cmr@informatik.wtf
# < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version
# < git log --format=%s --max-count=1 5faa15883ebc90132b58c685316de2cd24735e90
# < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_83xx_mpc832x_mds_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  83xx/mpc832x_mds_defconfig
# make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_83xx_mpc832x_mds_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
INFO: Uncompressed kernel (size 0x5309c0) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0x600000)
INFO: Uncompressed kernel (size 0x5202a8) overlaps the address of the wrapper(0x400000)
INFO: Fixing the link_address of wrapper to (0x600000)
Image Name:   Linux-5.3.0-rc2-g5faa15883ebc
Created:      Sun Aug 25 22:53:32 2019
Image Type:   PowerPC Linux Kernel Image (gzip compressed)
Data Size:    2607470 Bytes = 2546.36 KiB = 2.49 MiB
Load Address: 00000000
Entry Point:  00000000
Image Name:   Linux-5.3.0-rc2-g5faa15883ebc
Created:      Sun Aug 25 22:53:32 2019
Image Type:   PowerPC Linux Kernel Image (gzip compressed)
Data Size:    2635387 Bytes = 2573.62 KiB = 2.51 MiB
Load Address: 00600000
Entry Point:  00600294
Completed OK
# rm -rf /kisskb/build/powerpc-next_83xx_mpc832x_mds_defconfig_powerpc-gcc5
# Build took: 0:00:43.579863