# git rev-parse -q --verify f8c29fc27feb230a3383204f22aa5474042f6ed8^{commit} f8c29fc27feb230a3383204f22aa5474042f6ed8 already have revision, skipping fetch # git checkout -q -f -B kisskb f8c29fc27feb230a3383204f22aa5474042f6ed8 # git clean -qxdf # < git log -1 # commit f8c29fc27feb230a3383204f22aa5474042f6ed8 # Author: Michael Ellerman # Date: Mon Aug 19 22:24:01 2024 +1000 # # powerpc/pseries: Fix dtl_access_lock to be a rw_semaphore # # The dtl_access_lock needs to be a rw_sempahore, a sleeping lock, because # the code calls kmalloc() while holding it, which can sleep: # # # echo 1 > /proc/powerpc/vcpudispatch_stats # BUG: sleeping function called from invalid context at include/linux/sched/mm.h:337 # in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 199, name: sh # preempt_count: 1, expected: 0 # 3 locks held by sh/199: # #0: c00000000a0743f8 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x324/0x438 # #1: c0000000028c7058 (dtl_enable_mutex){+.+.}-{3:3}, at: vcpudispatch_stats_write+0xd4/0x5f4 # #2: c0000000028c70b8 (dtl_access_lock){+.+.}-{2:2}, at: vcpudispatch_stats_write+0x220/0x5f4 # CPU: 0 PID: 199 Comm: sh Not tainted 6.10.0-rc4 #152 # Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries # Call Trace: # dump_stack_lvl+0x130/0x148 (unreliable) # __might_resched+0x174/0x410 # kmem_cache_alloc_noprof+0x340/0x3d0 # alloc_dtl_buffers+0x124/0x1ac # vcpudispatch_stats_write+0x2a8/0x5f4 # proc_reg_write+0xf4/0x150 # vfs_write+0xfc/0x438 # ksys_write+0x88/0x148 # system_call_exception+0x1c4/0x5a0 # system_call_common+0xf4/0x258 # # Fixes: 06220d78f24a ("powerpc/pseries: Introduce rwlock to gatekeep DTLB usage") # Tested-by: Kajol Jain # Reviewed-by: Nysal Jan K.A # Reviewed-by: Kajol Jain # Signed-off-by: Michael Ellerman # Link: https://msgid.link/20240819122401.513203-1-mpe@ellerman.id.au # < /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 f8c29fc27feb230a3383204f22aa5474042f6ed8 # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_83xx_mpc8315_rdb_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- 83xx/mpc8315_rdb_defconfig # < make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_83xx_mpc8315_rdb_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_83xx_mpc8315_rdb_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 40 ARCH=powerpc O=/kisskb/build/powerpc-fixes_83xx_mpc8315_rdb_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux- Completed OK # rm -rf /kisskb/build/powerpc-fixes_83xx_mpc8315_rdb_defconfig_powerpc-gcc5 # Build took: 0:00:33.408272