diff options
| author | Pnina Feder <pnina.feder@mobileye.com> | 2025-12-16 15:28:01 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-20 19:44:20 -0800 |
| commit | b5bfcc1ffe512c7879cb90befdeabaa43d9f07ca (patch) | |
| tree | 5eece0f81ded891f28dbe3388626e2b0a954a51f /kernel | |
| parent | 76103d1b268e6f45735aa92d70bea5b5e8174a70 (diff) | |
kernel/crash: handle multi-page vmcoreinfo in crash kernel copy
kimage_crash_copy_vmcoreinfo() currently assumes vmcoreinfo fits in a
single page. This breaks if VMCOREINFO_BYTES exceeds PAGE_SIZE.
Allocate the required order of control pages and vmap all pages needed to
safely copy vmcoreinfo into the crash kernel image.
Link: https://lkml.kernel.org/r/20251216132801.807260-3-pnina.feder@mobileye.com
Signed-off-by: Pnina Feder <pnina.feder@mobileye.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/crash_core.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 99dac1aa972a..3952b3e102e0 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -44,9 +44,15 @@ note_buf_t __percpu *crash_notes; int kimage_crash_copy_vmcoreinfo(struct kimage *image) { - struct page *vmcoreinfo_page; + struct page *vmcoreinfo_base; + struct page *vmcoreinfo_pages[DIV_ROUND_UP(VMCOREINFO_BYTES, PAGE_SIZE)]; + unsigned int order, nr_pages; + int i; void *safecopy; + nr_pages = DIV_ROUND_UP(VMCOREINFO_BYTES, PAGE_SIZE); + order = get_order(VMCOREINFO_BYTES); + if (!IS_ENABLED(CONFIG_CRASH_DUMP)) return 0; if (image->type != KEXEC_TYPE_CRASH) @@ -61,12 +67,15 @@ int kimage_crash_copy_vmcoreinfo(struct kimage *image) * happens to generate vmcoreinfo note, hereby we rely on * vmap for this purpose. */ - vmcoreinfo_page = kimage_alloc_control_pages(image, 0); - if (!vmcoreinfo_page) { + vmcoreinfo_base = kimage_alloc_control_pages(image, order); + if (!vmcoreinfo_base) { pr_warn("Could not allocate vmcoreinfo buffer\n"); return -ENOMEM; } - safecopy = vmap(&vmcoreinfo_page, 1, VM_MAP, PAGE_KERNEL); + for (i = 0; i < nr_pages; i++) + vmcoreinfo_pages[i] = vmcoreinfo_base + i; + + safecopy = vmap(vmcoreinfo_pages, nr_pages, VM_MAP, PAGE_KERNEL); if (!safecopy) { pr_warn("Could not vmap vmcoreinfo buffer\n"); return -ENOMEM; |