Fix: commit 4230e2deaa484b385aa01d598b2aea8e7f2660a6 from https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
** Description changed: - 5.8.0-1-generic (buildd@riscv64-qemu-lcy01-015) (gcc (Ubuntu + == SRU Groovy == + + Running the ftrace self tests results in null pointer dereference oops + on RISC-V and also on ARM64. + + == Fix == + + Upstream commit + https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=4230e2deaa484b385aa01d598b2aea8e7f2660a6 + + == Testcase == + + Run the kernel ftrace selftest. Without the fix ftrace oopses on RISC-V + and ARM64 and can also hang on ARM64 too. With the fix, tests run + without oopsing or hanging. + + == Regression Potential == + + This fix marks two functions as notrace, so the functionality of the + functions is not actually altered so the risk is negligible. The only + chage is the the functions are no longer traceable via ftrace, which is + the desired operation. + + + ----------------- + + 5.8.0-1-generic (buildd@riscv64-qemu-lcy01-015) (gcc (Ubuntu 10.2.0-5ubuntu2) 10.2.0, GNU ld (GNU Binutils for Ubuntu) 2.35) #1-Ubuntu SMP Thu Aug 27 19:51:38 UTC 2020 (Ubuntu 5.8.0-1.1-generic 5.8.4 - 18:30:06 DEBUG| [stdout] # selftests: ftrace: ftracetest^M^M 18:30:07 DEBUG| [stdout] # === Ftrace unit tests ===^M^M 18:30:10 DEBUG| [stdout] # [1] Basic trace file check [PASS]^M^M [17433.113458] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113533] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113552] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113573] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113591] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114290] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114306] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114315] Oops [#1]^M^M [17433.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114690] Modules linked in: virtio_rng binfmt_misc uio_pdrv_genirq uio drm sch_fq_codel drm_panel_orientation_quirks backlight ip_tables x_tables autofs4 virtio_net net_failover virtio_blk failover [last unloaded: signpost]^M^M [17433.115296] CPU: 1 PID: 15 Comm: migration/1 Tainted: G W OE 5.8.0-1-generic #1-Ubuntu^M^M [17433.115419] epc: 0000000000000000 ra : 0000000000000000 sp : ffffffe1f5c67d90^M^M [17433.115442] gp : ffffffe001722298 tp : ffffffe1f5c3ae00 t0 : 0000000000000000^M^M [17433.115459] t1 : 0000000000006000 t2 : 00000000000bbc00 s0 : 0000000000000022^M^M [17433.115475] s1 : ffffffe0002b7c12 a0 : ffffffe000963a64 a1 : 0000000000000022^M^M [17433.115491] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000^M^M [17433.115507] a5 : ffffffe1fec95580 a6 : 00000000000000ff a7 : 0000000000000001^M^M [17433.115523] s2 : 0000000000000001 s3 : ffffffe00009d580 s4 : ffffffe001724210^M^M [17433.115540] s5 : ffffffe1fec9a3b8 s6 : ffffffffffffffff s7 : 0000000000000001^M^M [17433.115556] s8 : ffffffe0016f07cb s9 : ffffffe1e909bb80 s10: ffffffe0002b7ba6^M^M [17433.115573] s11: ffffffe1e909bba8 t3 : 000000000000006c t4 : 00000000002c73ba^M^M [17433.115586] t5 : 00000000001f7fa8 t6 : ffffffe000c02d1c^M^M [17433.115603] status: 0000000000000120 badaddr: 0000000000000000 cause: 000000000000000c^M^M ** Description changed: == SRU Groovy == Running the ftrace self tests results in null pointer dereference oops on RISC-V and also on ARM64. == Fix == Upstream commit https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=4230e2deaa484b385aa01d598b2aea8e7f2660a6 == Testcase == Run the kernel ftrace selftest. Without the fix ftrace oopses on RISC-V and ARM64 and can also hang on ARM64 too. With the fix, tests run without oopsing or hanging. == Regression Potential == This fix marks two functions as notrace, so the functionality of the functions is not actually altered so the risk is negligible. The only chage is the the functions are no longer traceable via ftrace, which is the desired operation. - ----------------- 5.8.0-1-generic (buildd@riscv64-qemu-lcy01-015) (gcc (Ubuntu 10.2.0-5ubuntu2) 10.2.0, GNU ld (GNU Binutils for Ubuntu) 2.35) #1-Ubuntu SMP Thu Aug 27 19:51:38 UTC 2020 (Ubuntu 5.8.0-1.1-generic 5.8.4 18:30:06 DEBUG| [stdout] # selftests: ftrace: ftracetest^M^M 18:30:07 DEBUG| [stdout] # === Ftrace unit tests ===^M^M 18:30:10 DEBUG| [stdout] # [1] Basic trace file check [PASS]^M^M [17433.113458] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113533] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113552] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113573] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113591] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114290] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114306] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114315] Oops [#1]^M^M [17433.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114690] Modules linked in: virtio_rng binfmt_misc uio_pdrv_genirq uio drm sch_fq_codel drm_panel_orientation_quirks backlight ip_tables x_tables autofs4 virtio_net net_failover virtio_blk failover [last unloaded: signpost]^M^M [17433.115296] CPU: 1 PID: 15 Comm: migration/1 Tainted: G W OE 5.8.0-1-generic #1-Ubuntu^M^M [17433.115419] epc: 0000000000000000 ra : 0000000000000000 sp : ffffffe1f5c67d90^M^M [17433.115442] gp : ffffffe001722298 tp : ffffffe1f5c3ae00 t0 : 0000000000000000^M^M [17433.115459] t1 : 0000000000006000 t2 : 00000000000bbc00 s0 : 0000000000000022^M^M [17433.115475] s1 : ffffffe0002b7c12 a0 : ffffffe000963a64 a1 : 0000000000000022^M^M [17433.115491] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000^M^M [17433.115507] a5 : ffffffe1fec95580 a6 : 00000000000000ff a7 : 0000000000000001^M^M [17433.115523] s2 : 0000000000000001 s3 : ffffffe00009d580 s4 : ffffffe001724210^M^M [17433.115540] s5 : ffffffe1fec9a3b8 s6 : ffffffffffffffff s7 : 0000000000000001^M^M [17433.115556] s8 : ffffffe0016f07cb s9 : ffffffe1e909bb80 s10: ffffffe0002b7ba6^M^M [17433.115573] s11: ffffffe1e909bba8 t3 : 000000000000006c t4 : 00000000002c73ba^M^M [17433.115586] t5 : 00000000001f7fa8 t6 : ffffffe000c02d1c^M^M [17433.115603] status: 0000000000000120 badaddr: 0000000000000000 cause: 000000000000000c^M^M ** Description changed: == SRU Groovy == Running the ftrace self tests results in null pointer dereference oops on RISC-V and also on ARM64. == Fix == Upstream commit https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=4230e2deaa484b385aa01d598b2aea8e7f2660a6 == Testcase == Run the kernel ftrace selftest. Without the fix ftrace oopses on RISC-V and ARM64 and can also hang on ARM64 too. With the fix, tests run without oopsing or hanging. == Regression Potential == This fix marks two functions as notrace, so the functionality of the - functions is not actually altered so the risk is negligible. The only - chage is the the functions are no longer traceable via ftrace, which is - the desired operation. + functions is not actually altered so the risk is negligible. If there + was a change in behaviour then RCU and stop machine operations will + break causing machine hangs. We don't observe this and RCU is used + heavily in the kernel so the code appears to not change the behaviour as + expected. + + The only change is the the functions are no longer traceable via ftrace, + which is the desired operation. ----------------- 5.8.0-1-generic (buildd@riscv64-qemu-lcy01-015) (gcc (Ubuntu 10.2.0-5ubuntu2) 10.2.0, GNU ld (GNU Binutils for Ubuntu) 2.35) #1-Ubuntu SMP Thu Aug 27 19:51:38 UTC 2020 (Ubuntu 5.8.0-1.1-generic 5.8.4 18:30:06 DEBUG| [stdout] # selftests: ftrace: ftracetest^M^M 18:30:07 DEBUG| [stdout] # === Ftrace unit tests ===^M^M 18:30:10 DEBUG| [stdout] # [1] Basic trace file check [PASS]^M^M [17433.113458] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113533] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113552] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113573] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.113591] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114290] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114306] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114315] Oops [#1]^M^M [17433.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000^M^M [17433.114690] Modules linked in: virtio_rng binfmt_misc uio_pdrv_genirq uio drm sch_fq_codel drm_panel_orientation_quirks backlight ip_tables x_tables autofs4 virtio_net net_failover virtio_blk failover [last unloaded: signpost]^M^M [17433.115296] CPU: 1 PID: 15 Comm: migration/1 Tainted: G W OE 5.8.0-1-generic #1-Ubuntu^M^M [17433.115419] epc: 0000000000000000 ra : 0000000000000000 sp : ffffffe1f5c67d90^M^M [17433.115442] gp : ffffffe001722298 tp : ffffffe1f5c3ae00 t0 : 0000000000000000^M^M [17433.115459] t1 : 0000000000006000 t2 : 00000000000bbc00 s0 : 0000000000000022^M^M [17433.115475] s1 : ffffffe0002b7c12 a0 : ffffffe000963a64 a1 : 0000000000000022^M^M [17433.115491] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000^M^M [17433.115507] a5 : ffffffe1fec95580 a6 : 00000000000000ff a7 : 0000000000000001^M^M [17433.115523] s2 : 0000000000000001 s3 : ffffffe00009d580 s4 : ffffffe001724210^M^M [17433.115540] s5 : ffffffe1fec9a3b8 s6 : ffffffffffffffff s7 : 0000000000000001^M^M [17433.115556] s8 : ffffffe0016f07cb s9 : ffffffe1e909bb80 s10: ffffffe0002b7ba6^M^M [17433.115573] s11: ffffffe1e909bba8 t3 : 000000000000006c t4 : 00000000002c73ba^M^M [17433.115586] t5 : 00000000001f7fa8 t6 : ffffffe000c02d1c^M^M [17433.115603] status: 0000000000000120 badaddr: 0000000000000000 cause: 000000000000000c^M^M -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1894613 Title: risc-v 5.8 kernel oops on ftrace tests To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1894613/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs