On 7/1/2026 9:43 PM, Masami Hiramatsu wrote: > On Wed, 1 Jul 2026 12:14:54 +0000 > Pu Hu <[email protected]> wrote: > >> From: hupu <[email protected]> >> >> This series fixes two arm64 kprobes issues observed when running >> simpleperf with preemptirq tracepoints and dwarf callchains while a >> kprobe is active on a frequently executed kernel function. >> >> The crash happens in the kprobe debug exception path. While a kprobe is >> preparing or executing its XOL single-step instruction, perf/trace code >> can run in the same window. That code may either take a fault of its own >> or hit another kprobe. >> >> Patch 1 makes kprobe_fault_handler() handle a fault in >> KPROBE_HIT_SS/KPROBE_REENTER only when the faulting PC points at the >> current kprobe's XOL instruction. Otherwise the fault is left to the >> normal fault handling path. >> >> Patch 2 allows a kprobe hit in KPROBE_HIT_SS to be handled as a >> recoverable one-level reentry. Only a hit while already in >> KPROBE_REENTER remains unrecoverable. >> >> This follows the same logic as the existing x86 fixes: >> 6381c24cd6d5 ("kprobes/x86: Fix page-fault handling logic") >> 6a5022a56ac3 ("kprobes/x86: Allow to handle reentered kprobe on >> single-stepping") > > Good catch!! > The series looks good to me. > > Acked-by: Masami Hiramatsu (Google) <[email protected]> > > But it should be reviewed by arm64 maintainers too. > > BTW, if you are "Pu Hu", the Signed-off-by tag should be > "Pu Hu <...>" instead of "hupu <...>". >
Hi Masami, Thank you for your reply and Acked-by. Yes, thanks for pointing this out. I will fix the author name and the Signed-off-by tags to use a consistent name in the next version of the patchset. Thanks, hupu
