diff options
| author | Pnina Feder <pnina.feder@mobileye.com> | 2025-12-16 15:28:00 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-20 19:44:20 -0800 |
| commit | 76103d1b268e6f45735aa92d70bea5b5e8174a70 (patch) | |
| tree | cd4022072fb58fbe4ce70fc7200f3cdf166bf49e /kernel | |
| parent | 61e9210e23921cf1176af23b426b9bad8b08ffff (diff) | |
kernel: vmcoreinfo: allocate vmcoreinfo_data based on VMCOREINFO_BYTES
Patch series "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE".
VMCOREINFO_BYTES is defined as a configurable size, but multiple
code paths implicitly assume it always fits into a single page.
This series removes that assumption by allocating and mapping
vmcoreinfo based on its actual size.
Patch 1 updates vmcoreinfo allocation to use get_order(VMCOREINFO_BYTES).
Patch 2 updates crash kernel handling to correctly allocate and map
multiple pages when copying vmcoreinfo.
This makes vmcoreinfo size consistent across the kernel and avoids
future breakage if VMCOREINFO_BYTES grows.
(No functional change when VMCOREINFO_BYTES == PAGE_SIZE.)
This patch (of 2):
VMCOREINFO_BYTES defines the size of vmcoreinfo data, but the current
implementation assumes a single page allocation.
Allocate vmcoreinfo_data using get_order(VMCOREINFO_BYTES) so that
vmcoreinfo can safely grow beyond PAGE_SIZE.
This avoids hidden assumptions and keeps vmcoreinfo size consistent across
the kernel.
Link: https://lkml.kernel.org/r/20251216132801.807260-1-pnina.feder@mobileye.com
Link: https://lkml.kernel.org/r/20251216132801.807260-2-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/vmcore_info.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/vmcore_info.c b/kernel/vmcore_info.c index fe9bf8db1922..22b3205dd4dc 100644 --- a/kernel/vmcore_info.c +++ b/kernel/vmcore_info.c @@ -137,7 +137,9 @@ EXPORT_SYMBOL_GPL(hwerr_log_error_type); static int __init crash_save_vmcoreinfo_init(void) { - vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL); + int order; + order = get_order(VMCOREINFO_BYTES); + vmcoreinfo_data = (unsigned char *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); if (!vmcoreinfo_data) { pr_warn("Memory allocation for vmcoreinfo_data failed\n"); return -ENOMEM; @@ -146,7 +148,7 @@ static int __init crash_save_vmcoreinfo_init(void) vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE, GFP_KERNEL | __GFP_ZERO); if (!vmcoreinfo_note) { - free_page((unsigned long)vmcoreinfo_data); + free_pages((unsigned long)vmcoreinfo_data, order); vmcoreinfo_data = NULL; pr_warn("Memory allocation for vmcoreinfo_note failed\n"); return -ENOMEM; |