The branch main has been updated by andrew: URL: https://cgit.FreeBSD.org/src/commit/?id=93d3ac1daa0ef3ac54ffcd5cc64a14638d04bd60
commit 93d3ac1daa0ef3ac54ffcd5cc64a14638d04bd60 Author: Andy Carrel <[email protected]> AuthorDate: 2026-01-05 07:50:27 +0000 Commit: Andrew Turner <[email protected]> CommitDate: 2026-01-30 17:01:49 +0000 arm64: Fix kernel panic in get_arm64_sve during core dump The coredump logic calls get_arm64_sve twice: once to get the note size, and once to get the data. The note size calculation depended on the volatile `PCB_FP_SVEVALID` flag. If this flag was cleared between the two calls (e.g., due to a context switch clearing the flag to comply with the ABI), the second call would expect a smaller buffer size than the first, triggering a KASSERT panic ("invalid size"). Fix this by ensuring the SVE state is saved to the PCB before we decide whether to use SVE or VFP. PR: 292195 Reviewed by: andrew Differential Revision: https://reviews.freebsd.org/D54532 --- sys/arm64/arm64/vfp.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/sys/arm64/arm64/vfp.c b/sys/arm64/arm64/vfp.c index bcddebfaf66e..64f13458e2d9 100644 --- a/sys/arm64/arm64/vfp.c +++ b/sys/arm64/arm64/vfp.c @@ -934,6 +934,9 @@ get_arm64_sve(struct regset *rs, struct thread *td, void *buf, pcb = td->td_pcb; + if (td == curthread && (pcb->pcb_fpflags & PCB_FP_STARTED) != 0) + vfp_save_state(td, pcb); + /* If there is no SVE support in HW then we don't support NT_ARM_SVE */ if (pcb->pcb_sve_len == 0) return (false); @@ -955,9 +958,6 @@ get_arm64_sve(struct regset *rs, struct thread *td, void *buf, KASSERT(*sizep == sizeof(struct svereg_header) + buf_size, ("%s: invalid size", __func__)); - if (td == curthread && (pcb->pcb_fpflags & PCB_FP_STARTED) != 0) - vfp_save_state(td, pcb); - header = buf; memset(header, 0, sizeof(*header));
