[PATCH 1/2] kernel: vmcoreinfo: allocate vmcoreinfo_data based on VMCOREINFO_BYTES

Pnina Feder posted 2 patches 2 days, 10 hours ago
[PATCH 1/2] kernel: vmcoreinfo: allocate vmcoreinfo_data based on VMCOREINFO_BYTES
Posted by Pnina Feder 2 days, 10 hours ago
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.

Signed-off-by: Pnina Feder <pnina.feder@mobileye.com>
---
 kernel/vmcore_info.c | 6 ++++--
 1 file 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;
-- 
2.43.0