# git rev-parse -q --verify 4ff753feab021242144818b9a3ba011238218145^{commit} 4ff753feab021242144818b9a3ba011238218145 already have revision, skipping fetch # git checkout -q -f -B kisskb 4ff753feab021242144818b9a3ba011238218145 # git clean -qxdf # < git log -1 # commit 4ff753feab021242144818b9a3ba011238218145 # Author: Ganesh Goudar # Date: Fri Jul 24 12:09:46 2020 +0530 # # powerpc/pseries: Avoid using addr_to_pfn in real mode # # When an UE or memory error exception is encountered the MCE handler # tries to find the pfn using addr_to_pfn() which takes effective # address as an argument, later pfn is used to poison the page where # memory error occurred, recent rework in this area made addr_to_pfn # to run in real mode, which can be fatal as it may try to access # memory outside RMO region. # # Have two helper functions to separate things to be done in real mode # and virtual mode without changing any functionality. This also fixes # the following error as the use of addr_to_pfn is now moved to virtual # mode. # # Without this change following kernel crash is seen on hitting UE. # # [ 485.128036] Oops: Kernel access of bad area, sig: 11 [#1] # [ 485.128040] LE SMP NR_CPUS=2048 NUMA pSeries # [ 485.128047] Modules linked in: # [ 485.128067] CPU: 15 PID: 6536 Comm: insmod Kdump: loaded Tainted: G OE 5.7.0 #22 # [ 485.128074] NIP: c00000000009b24c LR: c0000000000398d8 CTR: c000000000cd57c0 # [ 485.128078] REGS: c000000003f1f970 TRAP: 0300 Tainted: G OE (5.7.0) # [ 485.128082] MSR: 8000000000001003 CR: 28008284 XER: 00000001 # [ 485.128088] CFAR: c00000000009b190 DAR: c0000001fab00000 DSISR: 40000000 IRQMASK: 1 # [ 485.128088] GPR00: 0000000000000001 c000000003f1fbf0 c000000001634300 0000b0fa01000000 # [ 485.128088] GPR04: d000000002220000 0000000000000000 00000000fab00000 0000000000000022 # [ 485.128088] GPR08: c0000001fab00000 0000000000000000 c0000001fab00000 c000000003f1fc14 # [ 485.128088] GPR12: 0000000000000008 c000000003ff5880 d000000002100008 0000000000000000 # [ 485.128088] GPR16: 000000000000ff20 000000000000fff1 000000000000fff2 d0000000021a1100 # [ 485.128088] GPR20: d000000002200000 c00000015c893c50 c000000000d49b28 c00000015c893c50 # [ 485.128088] GPR24: d0000000021a0d08 c0000000014e5da8 d0000000021a0818 000000000000000a # [ 485.128088] GPR28: 0000000000000008 000000000000000a c0000000017e2970 000000000000000a # [ 485.128125] NIP [c00000000009b24c] __find_linux_pte+0x11c/0x310 # [ 485.128130] LR [c0000000000398d8] addr_to_pfn+0x138/0x170 # [ 485.128133] Call Trace: # [ 485.128135] Instruction dump: # [ 485.128138] 3929ffff 7d4a3378 7c883c36 7d2907b4 794a1564 7d294038 794af082 3900ffff # [ 485.128144] 79291f24 790af00e 78e70020 7d095214 <7c69502a> 2fa30000 419e011c 70690040 # [ 485.128152] ---[ end trace d34b27e29ae0e340 ]--- # # Fixes: 9ca766f9891d ("powerpc/64s/pseries: machine check convert to use common event code") # Signed-off-by: Ganesh Goudar # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20200724063946.21378-1-ganeshgr@linux.ibm.com # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux-ld --version # < git log --format=%s --max-count=1 4ff753feab021242144818b9a3ba011238218145 # < make -s -j 8 ARCH=m68k O=/kisskb/build/powerpc-fixes_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- defconfig # < make -s -j 8 ARCH=m68k O=/kisskb/build/powerpc-fixes_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- help # make -s -j 8 ARCH=m68k O=/kisskb/build/powerpc-fixes_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- olddefconfig # make -s -j 8 ARCH=m68k O=/kisskb/build/powerpc-fixes_m68k-defconfig_m68k-gcc8 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-8.1.0-nolibc/m68k-linux/bin/m68k-linux- /kisskb/src/arch/m68k/mvme147/config.c: In function 'mvme147_hwclk': /kisskb/src/arch/m68k/mvme147/config.c:174:2: warning: #warning check me! [-Wcpp] #warning check me! ^~~~~~~ /kisskb/src/arch/m68k/mvme16x/config.c: In function 'mvme16x_hwclk': /kisskb/src/arch/m68k/mvme16x/config.c:439:2: warning: #warning check me! [-Wcpp] #warning check me! ^~~~~~~ In file included from /kisskb/src/drivers/net/ethernet/8390/xsurf100.c:48: /kisskb/src/drivers/net/ethernet/8390/lib8390.c:988:27: warning: '____alloc_ei_netdev' defined but not used [-Wunused-function] static struct net_device *____alloc_ei_netdev(int size) ^~~~~~~~~~~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:950:13: warning: '__ei_set_multicast_list' defined but not used [-Wunused-function] static void __ei_set_multicast_list(struct net_device *dev) ^~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:850:33: warning: '__ei_get_stats' defined but not used [-Wunused-function] static struct net_device_stats *__ei_get_stats(struct net_device *dev) ^~~~~~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:509:13: warning: '__ei_poll' defined but not used [-Wunused-function] static void __ei_poll(struct net_device *dev) ^~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:300:20: warning: '__ei_start_xmit' defined but not used [-Wunused-function] static netdev_tx_t __ei_start_xmit(struct sk_buff *skb, ^~~~~~~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:254:13: warning: '__ei_tx_timeout' defined but not used [-Wunused-function] static void __ei_tx_timeout(struct net_device *dev, unsigned int txqueue) ^~~~~~~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:230:12: warning: '__ei_close' defined but not used [-Wunused-function] static int __ei_close(struct net_device *dev) ^~~~~~~~~~ /kisskb/src/drivers/net/ethernet/8390/lib8390.c:201:12: warning: '__ei_open' defined but not used [-Wunused-function] static int __ei_open(struct net_device *dev) ^~~~~~~~~ In file included from /kisskb/src/arch/m68k/include/asm/atomic.h:7, from /kisskb/src/include/linux/atomic.h:7, from /kisskb/src/include/linux/cpumask.h:13, from /kisskb/src/include/linux/smp.h:13, from /kisskb/src/include/linux/lockdep.h:14, from /kisskb/src/include/linux/spinlock.h:59, from /kisskb/src/include/linux/wait.h:9, from /kisskb/src/include/linux/wait_bit.h:8, from /kisskb/src/include/linux/fs.h:6, from /kisskb/src/fs/ocfs2/file.c:13: /kisskb/src/fs/ocfs2/file.c: In function 'ocfs2_file_write_iter': /kisskb/src/arch/m68k/include/asm/cmpxchg.h:79:22: warning: value computed is not used [-Wunused-value] #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /kisskb/src/fs/ocfs2/file.c:2419:3: note: in expansion of macro 'xchg' xchg(&iocb->ki_complete, saved_ki_complete); ^~~~ Completed OK # rm -rf /kisskb/build/powerpc-fixes_m68k-defconfig_m68k-gcc8 # Build took: 0:03:35.275295