The patch titled
Subject: initramfs: panic with memory information
has been added to the -mm tree. Its filename is
initramfs-panic-with-memory-information.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/initramfs-panic-with-memory-information.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/initramfs-panic-with-memory-information.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Florian Fainelli <f.fainelli@xxxxxxxxx>
Subject: initramfs: panic with memory information
On systems with large amounts of reserved memory we may fail to
successfully complete unpack_to_rootfs() and be left with:
Kernel panic - not syncing: write error
this is not too helpful to understand what happened, so let's wrap the
panic() calls with a surrounding show_mem() such that we have a chance of
understanding the memory conditions leading to these allocation failures.
Link: https://lkml.kernel.org/r/20210114231517.1854379-1-f.fainelli@xxxxxxxxx
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Cc: Barret Rhoden <brho@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
init/initramfs.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
--- a/init/initramfs.c~initramfs-panic-with-memory-information
+++ a/init/initramfs.c
@@ -11,6 +11,7 @@
#include <linux/utime.h>
#include <linux/file.h>
#include <linux/memblock.h>
+#include <linux/mm.h>
#include <linux/namei.h>
#include <linux/init_syscalls.h>
@@ -45,6 +46,11 @@ static void __init error(char *x)
message = x;
}
+#define panic_show_mem(...) { \
+ show_mem(0, NULL); \
+ panic(__VA_ARGS__); \
+}
+
/* link hash */
#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
@@ -80,7 +86,7 @@ static char __init *find_link(int major,
}
q = kmalloc(sizeof(struct hash), GFP_KERNEL);
if (!q)
- panic("can't allocate link hash entry");
+ panic_show_mem("can't allocate link hash entry");
q->major = major;
q->minor = minor;
q->ino = ino;
@@ -125,7 +131,7 @@ static void __init dir_add(const char *n
{
struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
if (!de)
- panic("can't allocate dir_entry buffer");
+ panic_show_mem("can't allocate dir_entry buffer");
INIT_LIST_HEAD(&de->list);
de->name = kstrdup(name, GFP_KERNEL);
de->mtime = mtime;
@@ -460,7 +466,7 @@ static char * __init unpack_to_rootfs(ch
name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
if (!header_buf || !symlink_buf || !name_buf)
- panic("can't allocate buffers");
+ panic_show_mem("can't allocate buffers");
state = Start;
this_header = 0;
@@ -607,7 +613,7 @@ static int __init populate_rootfs(void)
/* Load the built in initramfs */
char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
if (err)
- panic("%s", err); /* Failed to decompress INTERNAL initramfs */
+ panic_show_mem("%s", err); /* Failed to decompress INTERNAL initramfs */
if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
goto done;
_
Patches currently in -mm which might be from f.fainelli@xxxxxxxxx are
initramfs-panic-with-memory-information.patch
