# git rev-parse -q --verify 590ce02bd148cd35721560c140e3759e39a6e56a^{commit} 590ce02bd148cd35721560c140e3759e39a6e56a already have revision, skipping fetch # git checkout -q -f -B kisskb 590ce02bd148cd35721560c140e3759e39a6e56a # git clean -qxdf # < git log -1 # commit 590ce02bd148cd35721560c140e3759e39a6e56a # Author: Nicholas Piggin # Date: Wed Jul 22 17:34:37 2020 +1000 # # powerpc/64s: Fix irq tracing corruption in interrupt/syscall return caused by perf interrupts # # Alexey reports lockdep_assert_irqs_enabled() warnings when stress # testing perf, e.g., # # WARNING: CPU: 0 PID: 1556 at kernel/softirq.c:169 __local_bh_enable_ip+0x258/0x270 # CPU: 0 PID: 1556 Comm: syz-executor # NIP: c0000000001ec888 LR: c0000000001ec884 CTR: c000000000ef0610 # REGS: c000000022d4f8a0 TRAP: 0700 Not tainted (5.8.0-rc3-x) # MSR: 8000000000029033 CR: 28008844 XER: 20040000 # CFAR: c0000000001dc1d0 IRQMASK: 0 # # The interesting thing is MSR[EE] and IRQMASK shows interrupts are # enabled, suggesting the current->hardirqs_enabled irq tracing state is # going out of sync with the actual interrupt enable state. # # The cause is a window in interrupt/syscall return where irq tracing # state is being adjusted for an irqs-enabled return while MSR[EE] is # still enabled. A perf interrupt hits and ends up calling # trace_hardirqs_off() when restoring interrupt flags to a disable # state. # # Fix this by disabling perf interrupts as well while adjusting irq # tracing state. # # Add a debug check that catches the condition sooner. # # Fixes: 68b34588e202 ("powerpc/64/sycall: Implement syscall entry/exit logic in C") # Cc: stable@vger.kernel.org # v5.7+ # Reported-by: Alexey Kardashevskiy # Signed-off-by: Nicholas Piggin # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20200722073437.930521-1-npiggin@gmail.com # < /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 590ce02bd148cd35721560c140e3759e39a6e56a # < make -s -j 48 ARCH=mips O=/kisskb/build/powerpc-fixes_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 48 ARCH=mips O=/kisskb/build/powerpc-fixes_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 48 ARCH=mips O=/kisskb/build/powerpc-fixes_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 48 ARCH=mips O=/kisskb/build/powerpc-fixes_mips-defconfig_mips-gcc4.9 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-4.9.4-nolibc/mips-linux/bin/mips-linux- FIT description: Linux 5.8.0-rc2-31866-g590ce02bd148 Created: Fri Jul 24 01:31:21 2020 Image 0 (kernel@0) Description: Linux 5.8.0-rc2-31866-g590ce02bd148 Created: Fri Jul 24 01:31:21 2020 Type: Kernel Image Compression: gzip compressed Data Size: 5000236 Bytes = 4883.04 KiB = 4.77 MiB Architecture: MIPS OS: Linux Load Address: 0x80100000 Entry Point: 0x8092c1e0 Hash algo: sha1 Hash value: b96cffe10af90a6707df7eca7ef2db8bb70a4a56 Image 1 (fdt@boston) Description: img,boston Device Tree Created: Fri Jul 24 01:31:21 2020 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: Fri Jul 24 01:31:21 2020 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: Fri Jul 24 01:31:21 2020 Type: Flat Device Tree Compression: uncompressed Data Size: 4639 Bytes = 4.53 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: be2724f58b66c316a61da7c11ced633f4e7e86c7 Image 4 (fdt@ocelot_pcb120) Description: MSCC Ocelot PCB120 Device Tree Created: Fri Jul 24 01:31:21 2020 Type: Flat Device Tree Compression: uncompressed Data Size: 5198 Bytes = 5.08 KiB = 0.00 MiB Architecture: MIPS Hash algo: sha1 Hash value: 7556b1594bd7ab9e3b3fa939d8e3e03ae58fa180 Image 5 (fdt@xilfpga) Description: MIPSfpga (xilfpga) Device Tree Created: Fri Jul 24 01:31:21 2020 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-fixes_mips-defconfig_mips-gcc4.9 # Build took: 0:01:39.009352