[PATCH 0/1] sparc64: Fix tick/stick comparator equal-compare hazard
Tony Rodriguez <[email protected]> Mon, 18 May 2026 16:56:02 -0700
| Newsgroups | org.kernel.vger.sparclinux,dev.linux.lists.regressions,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
sparc64: avoid missed timer interrupts when comparator equals counter This patch fixes an equal‑compare hazard in the SPARC64 tick/stick comparator logic that can cause missed timer interrupts and stalled hrtimers. Full dmesg and crash dumps: https://github.com/unixpro1970/Sparc64-Kernel-Debugging-Dumps/blob/main/s7-2-05122026-dump.tar.gz Debugging discussion: https://lore.kernel.org/all/87tssb6olo.ffs@tglx/ https://lore.kernel.org/all/871pfcznw0.ffs@tglx/ Short dmesg excerpt: [ 48.632215] rcu: INFO: rcu_sched detected stalls on CPUs/tasks: [ 48.676018] rcu: rcu_sched kthread timer wakeup didn't happen for 5259 jiffies! [ 48.743621] rcu: Possible timer handling issue on cpu=100 timer-softirq=15 Test summary: After applying this patch, S7-2 and T7-1 systems no longer hang on v7 and v7.1 kernels. Tony Rodriguez (1): sparc64: Fix tick/stick comparator equal-compare hazard arch/sparc/kernel/time_64.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- 2.53.0