# git rev-parse -q --verify c7dee506ec3450717e84518ab3a6a3f2ce755cf6^{commit} c7dee506ec3450717e84518ab3a6a3f2ce755cf6 already have revision, skipping fetch # git checkout -q -f -B kisskb c7dee506ec3450717e84518ab3a6a3f2ce755cf6 # git clean -qxdf # < git log -1 # commit c7dee506ec3450717e84518ab3a6a3f2ce755cf6 # Author: Michael Ellerman # Date: Tue Aug 31 23:41:15 2021 +1000 # # powerpc/ptdump: Fix generic ptdump for 64-bit # # Since the conversion to generic ptdump we see crashes on 64-bit: # # BUG: Unable to handle kernel data access on read at 0xc0eeff7f00000000 # Faulting instruction address: 0xc00000000045e5fc # Oops: Kernel access of bad area, sig: 11 [#1] # ... # NIP __walk_page_range+0x2bc/0xce0 # LR __walk_page_range+0x240/0xce0 # Call Trace: # __walk_page_range+0x240/0xce0 (unreliable) # walk_page_range_novma+0x74/0xb0 # ptdump_walk_pgd+0x98/0x170 # ptdump_check_wx+0x88/0xd0 # mark_rodata_ro+0x48/0x80 # kernel_init+0x74/0x1a0 # ret_from_kernel_thread+0x5c/0x64 # # What's happening is that have walked off the end of the kernel page # tables, and started dereferencing junk values. # # That happens because we initialised the ptdump_range to span all the way # up to 0xffffffffffffffff: # # static struct ptdump_range ptdump_range[] __ro_after_init = { # {TASK_SIZE_MAX, ~0UL}, # # But the kernel page tables don't span that far. So on 64-bit set the end # of the range to be the address immediately past the end of the kernel # page tables, to limit the page table walk to valid addresses. # # Fixes: e084728393a5 ("powerpc/ptdump: Convert powerpc to GENERIC_PTDUMP") # Reported-by: Nathan Chancellor # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 c7dee506ec3450717e84518ab3a6a3f2ce755cf6 # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- mpc85xx_smp_defconfig # < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig # make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-next_mpc85xx_smp_defconfig_powerpc-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/powerpc64-linux/bin/powerpc64-linux- /kisskb/src/net/sched/sch_frag.c: In function 'sch_fragment': /kisskb/src/net/sched/sch_frag.c:93:10: warning: missing braces around initializer [-Wmissing-braces] struct rtable sch_frag_rt = { 0 }; ^ /kisskb/src/net/sched/sch_frag.c:93:10: warning: (near initialization for 'sch_frag_rt.dst') [-Wmissing-braces] In file included from /kisskb/src/include/linux/kernel.h:11:0, from /kisskb/src/include/linux/list.h:9, from /kisskb/src/include/linux/module.h:12, from /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:15: /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c: In function 'allocate_bd': /kisskb/src/include/linux/err.h:22:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) ^ /kisskb/src/include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' # define unlikely(x) __builtin_expect(!!(x), 0) ^ /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:139:6: note: in expansion of macro 'IS_ERR_VALUE' if (IS_ERR_VALUE(fep->ring_mem_addr)) ^ /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8541cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8555cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) Completed OK # rm -rf /kisskb/build/powerpc-next_mpc85xx_smp_defconfig_powerpc-gcc4.9 # Build took: 0:02:12.600123