[Crash-utility] Re: [PATCH v2] memory: Handle crash failure in linux-next caused by struct kmem_cache changes

LGTM, ack. Thanks, Tao Liu On Tue, Feb 17, 2026 at 8:39 AM Mikhail Zaslonko <zaslonko(a)linux.ibm.com&gt; wrote: > > Since kernel commit cf338283652f ("slab: remove struct kmem_cache_cpu") > in linux-next there is no more 'cpu_slab' member in struct kmem_cache. > Pick 'cpu_sheaves' as an alternative kmem_cache member for kernel-next to > identify the SLUB case. > > Without the patch, crash fails to start on kernel-next with the error > message: > > crash: invalid structure member offset: kmem_cache_s_num > FILE: memory.c LINE: 9988 FUNCTION: kmem_cache_init() > > This fix: > - allows the crash to start with no errors for kernel-next. > - make the 'kmap -s' command working again for kernel-next. > - throws an error message on 'kmem -S' command if no 'cpu_slab' member > presents in struct kmem_cache: > kmem: -S not supported for this kernel > > Signed-off-by: Mikhail Zaslonko <zaslonko(a)linux.ibm.com&gt; > --- > memory.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/memory.c b/memory.c > index cbc8d2f..17423a5 100644 > --- a/memory.c > +++ b/memory.c > @@ -672,6 +672,7 @@ vm_init(void) > } else if (!VALID_STRUCT(kmem_slab_s) && > !VALID_STRUCT(slab_s) && > !MEMBER_EXISTS("kmem_cache", "cpu_slab") && > + !MEMBER_EXISTS("kmem_cache", "cpu_sheaves") && > (VALID_STRUCT(slab) || (vt->flags & SLAB_OVERLOAD_PAGE))) { > vt->flags |= PERCPU_KMALLOC_V2; > > @@ -816,7 +817,7 @@ vm_init(void) > if (INVALID_MEMBER(page_first_page)) > ANON_MEMBER_OFFSET_INIT(page_first_page, "page", "first_page"); > > - } else if (MEMBER_EXISTS("kmem_cache", "cpu_slab") && > + } else if ((MEMBER_EXISTS("kmem_cache", "cpu_slab") || MEMBER_EXISTS("kmem_cache", "cpu_sheaves")) && > STRUCT_EXISTS("kmem_cache_node")) { > vt->flags |= KMALLOC_SLUB; > > @@ -5270,6 +5271,9 @@ cmd_kmem(void) > if (sflag || Sflag || rflag || !(vt->flags & KMEM_CACHE_INIT)) > kmem_cache_init(); > > + if (Sflag && !MEMBER_EXISTS("kmem_cache", "cpu_slab")) > + error(FATAL, "-S not supported for this kernel\n"); > + > while (args[optind]) { > if (hexadecimal(args[optind], 0)) { > value[spec_addr++] = > @@ -20401,7 +20405,6 @@ get_cpu_slab_ptr(struct meminfo *si, int cpu, ulong *cpu_freelist) > > default: > cpu_slab_ptr = 0; > - error(FATAL, "cannot determine location of kmem_cache.cpu_slab page\n"); > } > > return cpu_slab_ptr; > -- > 2.52.0 >