# git rev-parse -q --verify 19d767f0429ab26cb3de6c1f7a805a973c5dbd26^{commit} 19d767f0429ab26cb3de6c1f7a805a973c5dbd26 already have revision, skipping fetch # git checkout -q -f -B kisskb 19d767f0429ab26cb3de6c1f7a805a973c5dbd26 # git clean -qxdf # < git log -1 # commit 19d767f0429ab26cb3de6c1f7a805a973c5dbd26 # Author: Michael Ellerman # Date: Mon Mar 1 14:32:14 2021 +1100 # # KVM: PPC: Book3S HV: Convert tbacct/stoltb_lock to raw spinlocks # # With CONFIG_PROVE_RAW_LOCK_NESTING=y we see lockdep splats when # running KVM: # # ============================= # [ BUG: Invalid wait context ] # 5.11.0-11811-gb49a419bbf28 #1 Not tainted # ----------------------------- # qemu-system-ppc/14068 is trying to lock: # c000000134282100 (&vcpu->arch.tbacct_lock){....}-{3:3}, at: kvmppc_core_vcpu_put_hv+0x44/0xd0 [kvm_hv] # other info that might help us debug this: # context-{5:5} # 2 locks held by qemu-system-ppc/14068: # #0: c0000001342800c8 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0xdc/0x8c0 [kvm] # #1: c000001e612cfa98 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x1a4/0xdd0 # stack backtrace: # CPU: 10 PID: 14068 Comm: qemu-system-ppc Not tainted 5.11.0-11811-gb49a419bbf28 #1 # Call Trace: # dump_stack+0xec/0x144 (unreliable) # __lock_acquire+0xab0/0x2e70 # lock_acquire+0x128/0x600 # _raw_spin_lock_irqsave+0x6c/0xc0 # kvmppc_core_vcpu_put_hv+0x44/0xd0 [kvm_hv] # kvmppc_core_vcpu_put+0x34/0x50 [kvm] # kvm_arch_vcpu_put+0x20/0x40 [kvm] # kvm_sched_out+0x44/0x80 [kvm] # __schedule+0x684/0xdd0 # preempt_schedule_common+0x30/0x60 # __cond_resched+0x60/0x80 # kvmhv_run_single_vcpu+0xe2c/0x1220 [kvm_hv] # kvmppc_vcpu_run_hv+0x984/0xcd0 [kvm_hv] # kvmppc_vcpu_run+0x34/0x48 [kvm] # kvm_arch_vcpu_ioctl_run+0x340/0x450 [kvm] # kvm_vcpu_ioctl+0x2ac/0x8c0 [kvm] # sys_ioctl+0x300/0x1050 # system_call_exception+0x160/0x230 # system_call_common+0xec/0x278 # # Which is complaining that we're taking a regular # spinlock (tbacct_lock) while holding a raw spinlock (rq->lock). # # To fix it, convert tbacct_lock to a raw spinlock. # # We see a similar splat for stoltb_lock, the analysis & fix is the # same. # # Signed-off-by: Michael Ellerman # < /opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux-gcc --version # < /opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux-ld --version # < git log --format=%s --max-count=1 19d767f0429ab26cb3de6c1f7a805a973c5dbd26 # < make -s -j 48 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mipsel CROSS_COMPILE=/opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux- defconfig # < make -s -j 48 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mipsel CROSS_COMPILE=/opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux- help # make -s -j 48 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mipsel CROSS_COMPILE=/opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux- olddefconfig # make -s -j 48 ARCH=mips O=/kisskb/build/powerpc-next_mips-defconfig_mipsel CROSS_COMPILE=/opt/cross/kisskb/br-mipsel-o32-full-2016.08-613-ge98b4dd/bin/mipsel-linux- FIT description: Linux 5.12.0-rc1-g19d767f0429a Created: Tue Mar 2 05:30:37 2021 Image 0 (kernel@0) Description: Linux 5.12.0-rc1-g19d767f0429a Created: Tue Mar 2 05:30:37 2021 Type: Kernel Image Compression: gzip compressed Data Size: 5250392 Bytes = 5127.34 KiB = 5.01 MiB Architecture: MIPS OS: Linux Load Address: 0x80100000 Entry Point: 0x809a7588 Hash algo: sha1 Hash value: 2a22e7f28f4bba35e084bc313a0972c443f13be0 Image 1 (fdt@boston) Description: img,boston Device Tree Created: Tue Mar 2 05:30:37 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: Tue Mar 2 05:30:37 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: Tue Mar 2 05:30:37 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: Tue Mar 2 05:30:37 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: Tue Mar 2 05:30:37 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_mipsel # Build took: 0:01:43.412487