| Message ID | 4BBCC648.30807@teksavvy.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On Wed, 07 Apr 2010 13:52:08 -0400 Mark Lord <kernel@teksavvy.com> wrote: > 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> Acked-by: Alan Cox <alan@linux.intel.com> -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/08/2010 02:52 AM, Mark Lord wrote: > 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> Heh, yeah, killing the cast works too. Acked-by: Tejun Heo <tj@kernel.org> Thanks.
On 04/07/2010 01:52 PM, Mark Lord wrote: > 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> > --- > > Reposting with the pre-existing (u64) cast removed. > > --- linux-2.6.34-rc3/include/linux/ata.h 2010-03-30 12:24:39.000000000 > -0400 > +++ linux/include/linux/ata.h 2010-04-06 18:39:41.167702612 -0400 > @@ -1025,8 +1025,8 @@ > > 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); > } applied. Neither 'git am' nor patch(1) would apply the patch for some reason, so I applied it manually. Weird... I could not spot obvious whitespace or word-wrap corruption. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 08/04/10 01:00 PM, Jeff Garzik wrote: > On 04/07/2010 01:52 PM, Mark Lord wrote: >> 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> >> --- >> >> Reposting with the pre-existing (u64) cast removed. >> >> --- linux-2.6.34-rc3/include/linux/ata.h 2010-03-30 12:24:39.000000000 >> -0400 >> +++ linux/include/linux/ata.h 2010-04-06 18:39:41.167702612 -0400 >> @@ -1025,8 +1025,8 @@ >> >> 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); >> } > > applied. > > Neither 'git am' nor patch(1) would apply the patch for some reason, so > I applied it manually. Weird... I could not spot obvious whitespace or > word-wrap corruption. .. I figured this this out (paritially) today: Somehow, the (v2) repost ended up with MS-DOS line separators (CR-LF). I imagine those would confuse most of the tools, yet remain transparent (hidden) in editors and email programs. Dunno how they got in there, though. Cheers -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- linux-2.6.34-rc3/include/linux/ata.h 2010-03-30 12:24:39.000000000 -0400 +++ linux/include/linux/ata.h 2010-04-06 18:39:41.167702612 -0400 @@ -1025,8 +1025,8 @@ 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)
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> --- Reposting with the pre-existing (u64) cast removed. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html