firmware_map: fix hang with x86/32bit
authorYinghai Lu <yinghai@kernel.org>
Tue, 16 Jun 2009 22:31:16 +0000 (15:31 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 17 Jun 2009 02:47:28 +0000 (19:47 -0700)
commit3b0fde0fac19c180317eb0601b3504083f4b9bf5
tree5458ec10f3c6759ec64c6fa27e12e692a575d07a
parent021415468c889979117b1a07b96f7e36de33e995
firmware_map: fix hang with x86/32bit

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13484

Peer reported:
| The bug is introduced from kernel 2.6.27, if E820 table reserve the memory
| above 4G in 32bit OS(BIOS-e820: 00000000fff80000 - 0000000120000000
| (reserved)), system will report Int 6 error and hang up. The bug is caused by
| the following code in drivers/firmware/memmap.c, the resource_size_t is 32bit
| variable in 32bit OS, the BUG_ON() will be invoked to result in the Int 6
| error. I try the latest 32bit Ubuntu and Fedora distributions, all hit this
| bug.
|======
|static int firmware_map_add_entry(resource_size_t start, resource_size_t end,
|                  const char *type,
|                  struct firmware_map_entry *entry)

and it only happen with CONFIG_PHYS_ADDR_T_64BIT is not set.

it turns out we need to pass u64 instead of resource_size_t for that.

[akpm@linux-foundation.org: add comment]
Reported-and-tested-by: Peer Chen <pchen@nvidia.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/firmware/memmap.c
include/linux/firmware-map.h