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.

[akpm@linux-foundation.org: replace macro with C function]

Link: https://lkml.kernel.org/r/20210114231517.1854379-1-f.fainelli@gmail.com
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Barret Rhoden <brho@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Florian Fainelli 2021-02-25 17:22:46 -08:00 committed by Linus Torvalds
parent 6aaa31aeb9
commit dd23e8098f

View File

@ -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 +46,16 @@ static void __init error(char *x)
message = x;
}
static void panic_show_mem(const char *fmt, ...)
{
va_list args;
show_mem(0, NULL);
va_start(args, fmt);
panic(fmt, args);
va_end(args);
}
/* link hash */
#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
@ -80,7 +91,7 @@ static char __init *find_link(int major, int minor, int ino,
}
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 +136,7 @@ static void __init dir_add(const char *name, time64_t mtime)
{
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 +471,7 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
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 +618,7 @@ 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;