Commit 45c4d015 authored Apr 07, 2010 by Mark Lord Committed by Jeff Garzik Apr 08, 2010

libata: Fix accesses at LBA28 boundary (old bug, but nasty) (v2)



Most drives from Seagate, Hitachi, and possibly other brands,
do not allow LBA28 access to sector number 0x0fffffff (2^28 - 1).
So instead use LBA48 for such accesses.

This bug could bite a lot of systems, especially when the user has
taken care to align partitions to 4KB boundaries. On misaligned systems,
it is less likely to be encountered, since a 4KB read would end at
0x10000000 rather than at 0x0fffffff.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

parent cf90bfe2

include/linux/ata.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -1025,8 +1025,8 @@ static inline int ata_ok(u8 status)

		static inline int lba_28_ok(u64 block, u32 n_block)
		{
		/* check the ending block number */
		return ((block + n_block) < ((u64)1 << 28)) && (n_block <= 256);
		/* check the ending block number: must be LESS THAN 0x0fffffff */
		return ((block + n_block) < ((1 << 28) - 1)) && (n_block <= 256);
		}

		static inline int lba_48_ok(u64 block, u32 n_block)

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