Buildresult: powerpc-next/mips-defconfig/mips-gcc4.9 built on Feb 4 2021, 00:47

kisskb

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Status:	OK
Date/Time:	Feb 4 2021, 00:47
Duration:	0:02:05.784777
Builder:	blade4b
Revision:	powerpc/kuap: Restore AMR after replaying soft interrupts (`006b445f18fa152c8e375abf4c68eab6d0b4afae)`
Target:	powerpc-next/mips-defconfig/mips-gcc4.9
Branch:	powerpc-next
Compiler:	mips-gcc4.9 (mips-linux-gcc (GCC) 4.9.4 / GNU ld (GNU Binutils) 2.29.1.20170915)
Config:	defconfig (download)
Log:	Download original Possible warnings (2) drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces] drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces] Full Log # git rev-parse -q --verify 006b445f18fa152c8e375abf4c68eab6d0b4afae^{commit} 006b445f18fa152c8e375abf4c68eab6d0b4afae already have revision, skipping fetch # git checkout -q -f -B kisskb 006b445f18fa152c8e375abf4c68eab6d0b4afae # git clean -qxdf # < git log -1 # commit 006b445f18fa152c8e375abf4c68eab6d0b4afae # Author: Alexey Kardashevskiy <aik@ozlabs.ru> # Date: Tue Feb 2 20:15:41 2021 +1100 # # powerpc/kuap: Restore AMR after replaying soft interrupts # # Since de78a9c42a79 ("powerpc: Add a framework for Kernel Userspace # Access Protection"), user access helpers call user_{read\|write}_access_{begin\|end} # when user space access is allowed. # # Commit 890274c2dc4c ("powerpc/64s: Implement KUAP for Radix MMU") made # the mentioned helpers program a AMR special register to allow such # access for a short period of time, most of the time AMR is expected to # block user memory access by the kernel. # # Since the code accesses the user space memory, unsafe_get_user() calls # might_fault() which calls arch_local_irq_restore() if either # CONFIG_PROVE_LOCKING or CONFIG_DEBUG_ATOMIC_SLEEP is enabled. # arch_local_irq_restore() then attempts to replay pending soft # interrupts as KUAP regions have hardware interrupts enabled. # # If a pending interrupt happens to do user access (performance # interrupts do that), it enables access for a short period of time so # after returning from the replay, the user access state remains blocked # and if a user page fault happens - "Bug: Read fault blocked by AMR!" # appears and SIGSEGV is sent. # # An example trace: # Bug: Read fault blocked by AMR! # WARNING: CPU: 0 PID: 1603 at /home/aik/p/kernel/arch/powerpc/include/asm/book3s/64/kup-radix.h:145 # CPU: 0 PID: 1603 Comm: amr Not tainted 5.10.0-rc6_v5.10-rc6_a+fstn1 #24 # NIP: c00000000009ece8 LR: c00000000009ece4 CTR: 0000000000000000 # REGS: c00000000dc63560 TRAP: 0700 Not tainted (5.10.0-rc6_v5.10-rc6_a+fstn1) # MSR: 8000000000021033 <SF,ME,IR,DR,RI,LE> CR: 28002888 XER: 20040000 # CFAR: c0000000001fa928 IRQMASK: 1 # GPR00: c00000000009ece4 c00000000dc637f0 c000000002397600 000000000000001f # GPR04: c0000000020eb318 0000000000000000 c00000000dc63494 0000000000000027 # GPR08: c00000007fe4de68 c00000000dfe9180 0000000000000000 0000000000000001 # GPR12: 0000000000002000 c0000000030a0000 0000000000000000 0000000000000000 # GPR16: 0000000000000000 0000000000000000 0000000000000000 bfffffffffffffff # GPR20: 0000000000000000 c0000000134a4020 c0000000019c2218 0000000000000fe0 # GPR24: 0000000000000000 0000000000000000 c00000000d106200 0000000040000000 # GPR28: 0000000000000000 0000000000000300 c00000000dc63910 c000000001946730 # NIP __do_page_fault+0xb38/0xde0 # LR __do_page_fault+0xb34/0xde0 # Call Trace: # __do_page_fault+0xb34/0xde0 (unreliable) # handle_page_fault+0x10/0x2c # --- interrupt: 300 at strncpy_from_user+0x290/0x440 # LR = strncpy_from_user+0x284/0x440 # strncpy_from_user+0x2f0/0x440 (unreliable) # getname_flags+0x88/0x2c0 # do_sys_openat2+0x2d4/0x5f0 # do_sys_open+0xcc/0x140 # system_call_exception+0x160/0x240 # system_call_common+0xf0/0x27c # # To fix it save/restore the AMR when replaying interrupts, and also # add a check if AMR was not blocked prior to replaying interrupts. # # Originally found by syzkaller. # # Fixes: 890274c2dc4c ("powerpc/64s: Implement KUAP for Radix MMU") # Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> # Reviewed-by: Nicholas Piggin <npiggin@gmail.com> # [mpe: Use normal commit citation format and add full oops log to change log] # Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> # Link: https://lore.kernel.org/r/20210202091541.36499-1-aik@ozlabs.ru # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux-ld --version # < git log --format=%s --max-count=1 006b445f18fa152c8e375abf4c68eab6d0b4afae # < make -s -j 24 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mips-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux- defconfig # < make -s -j 24 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mips-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux- help # make -s -j 24 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mips-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux- olddefconfig # make -s -j 24 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mips-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux- /kisskb/src/drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set': /kisskb/src/drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces] struct ocelot_vcap_u16 etype = {0}; ^ /kisskb/src/drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces] FIT description: Linux 5.11.0-rc2-g006b445f18fa Created: Thu Feb 4 00:49:11 2021 Image 0 (kernel@0) Description: Linux 5.11.0-rc2-g006b445f18fa Created: Thu Feb 4 00:49:11 2021 Type: Kernel Image Compression: gzip compressed Data Size: 5218615 Bytes = 5096.30 KiB = 4.98 MiB Architecture: MIPS OS: Linux Load Address: 0x80100000 Entry Point: 0x8098d938 Hash algo: sha1 Hash value: ce577c32f1949e35b84963a8427a3ba6c0b53f36 Image 1 (fdt@boston) Description: img,boston Device Tree Created: Thu Feb 4 00:49:11 2021 Type: Flat Device Tree Compression: uncompressed Data Size: 3793 Bytes = 3.70 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: 4799f50d688573234da6e9d7701234d394759ef4 Image 2 (fdt@ni169445) Description: NI 169445 device tree Created: Thu Feb 4 00:49:11 2021 Type: Flat Device Tree Compression: uncompressed Data Size: 1871 Bytes = 1.83 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: 51b89b31605ee62038c8468c429af091dfc75ec7 Image 3 (fdt@ocelot_pcb123) Description: MSCC Ocelot PCB123 Device Tree Created: Thu Feb 4 00:49:11 2021 Type: Flat Device Tree Compression: uncompressed Data Size: 4659 Bytes = 4.55 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: 5bcb6e4f21e8e5372544aa130b3bd097355a9050 Image 4 (fdt@ocelot_pcb120) Description: MSCC Ocelot PCB120 Device Tree Created: Thu Feb 4 00:49:11 2021 Type: Flat Device Tree Compression: uncompressed Data Size: 5418 Bytes = 5.29 KiB = 0.01 MiB Architecture: MIPS Hash algo: sha1 Hash value: 93d882f2009a217e0fa9dab94788535ed2be8476 Image 5 (fdt@xilfpga) Description: MIPSfpga (xilfpga) Device Tree Created: Thu Feb 4 00:49:11 2021 Type: Flat Device Tree Compression: uncompressed Data Size: 2708 Bytes = 2.64 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: 63d058b780f65e22da30f0a183433765f1807f1d Default Configuration: 'conf@default' Configuration 0 (conf@default) Description: Generic Linux kernel Kernel: kernel@0 Configuration 1 (conf@boston) Description: Boston Linux kernel Kernel: kernel@0 FDT: fdt@boston Configuration 2 (conf@ni169445) Description: NI 169445 Linux Kernel Kernel: kernel@0 FDT: fdt@ni169445 Configuration 3 (conf@ocelot_pcb123) Description: Ocelot Linux kernel Kernel: kernel@0 FDT: fdt@ocelot_pcb123 Configuration 4 (conf@ocelot_pcb120) Description: Ocelot Linux kernel Kernel: kernel@0 FDT: fdt@ocelot_pcb120 Configuration 5 (conf@xilfpga) Description: MIPSfpga Linux kernel Kernel: kernel@0 FDT: fdt@xilfpga Completed OK # rm -rf /kisskb/build/powerpc-next_mips-defconfig_mips-gcc4.9 # Build took: 0:02:05.784777

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