Mark Nelson e423b9ecd6 powerpc: Fix 64bit memcpy() regression ... This fixes a regression introduced by commit 25d6e2d7c5 ("powerpc: Update 64bit memcpy() using CPU_FTR_UNALIGNED_LD_STD"). This commit allowed CPUs that have the CPU_FTR_UNALIGNED_LD_STD CPU feature bit present to do the memcpy() with unaligned load doubles. But, along with this came a bug where our final load double would read bytes beyond a page boundary and into the next (unmapped) page. This was caught by enabling CONFIG_DEBUG_PAGEALLOC, The fix was to read only the number of bytes that we need to store rather than reading a full 8-byte doubleword and storing only a portion of that. In order to minimise the amount of existing code touched we use the original do_tail for the src_unaligned case. Below is an example of the regression, as reported by Sachin Sant: Unable to handle kernel paging request for data at address 0xc00000003f380000 Faulting instruction address: 0xc000000000039574 cpu 0x1: Vector: 300 (Data Access) at [c00000003baf3020] pc: c000000000039574: .memcpy+0x74/0x244 lr: d00000000244916c: .ext3_xattr_get+0x288/0x2f4 [ext3] sp: c00000003baf32a0 msr: 8000000000009032 dar: c00000003f380000 dsisr: 40000000 current = 0xc00000003e54b010 paca = 0xc000000000a53680 pid = 1840, comm = readahead enter ? for help [link register ] d00000000244916c .ext3_xattr_get+0x288/0x2f4 [ext3] [c00000003baf32a0] d000000002449104 .ext3_xattr_get+0x220/0x2f4 [ext3] (unreliab le) [c00000003baf3390] d00000000244a6e8 .ext3_xattr_security_get+0x40/0x5c [ext3] [c00000003baf3400] c000000000148154 .generic_getxattr+0x74/0x9c [c00000003baf34a0] c000000000333400 .inode_doinit_with_dentry+0x1c4/0x678 [c00000003baf3560] c00000000032c6b0 .security_d_instantiate+0x50/0x68 [c00000003baf35e0] c00000000013c818 .d_instantiate+0x78/0x9c [c00000003baf3680] c00000000013ced0 .d_splice_alias+0xf0/0x120 [c00000003baf3720] d00000000243e05c .ext3_lookup+0xec/0x134 [ext3] [c00000003baf37c0] c000000000131e74 .do_lookup+0x110/0x260 [c00000003baf3880] c000000000134ed0 .__link_path_walk+0xa98/0x1010 [c00000003baf3970] c0000000001354a0 .path_walk+0x58/0xc4 [c00000003baf3a20] c000000000135720 .do_path_lookup+0x138/0x1e4 [c00000003baf3ad0] c00000000013645c .path_lookup_open+0x6c/0xc8 [c00000003baf3b70] c000000000136780 .do_filp_open+0xcc/0x874 [c00000003baf3d10] c0000000001251e0 .do_sys_open+0x80/0x140 [c00000003baf3dc0] c00000000016aaec .compat_sys_open+0x24/0x38 [c00000003baf3e30] c00000000000855c syscall_exit+0x0/0x40 Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>		2009-02-26 14:02:53 +11:00
..
alloc.c
checksum_32.S
checksum_64.S
code-patching.c	PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures	2008-07-24 10:47:21 -07:00
copy_32.S
copypage_64.S	powerpc: New copy_4K_page()	2008-09-15 11:07:42 -07:00
copyuser_64.S	powerpc: Update 64bit __copy_tofrom_user() using CPU_FTR_UNALIGNED_LD_STD	2008-11-19 16:04:54 +11:00
crtsavres.S	[POWERPC] Fix -Os kernel builds with newer gcc versions	2008-06-16 15:00:54 +10:00
devres.c	[POWERPC] devres: Add devm_ioremap_prot()	2008-05-05 16:47:14 +10:00
div64.S
dma-noncoherent.c	powerpc: Rename struct vm_region to avoid conflict with NOMMU	2008-12-21 14:21:14 +11:00
feature-fixups-test.S	powerpc: Fixup lwsync at runtime	2008-07-03 16:58:10 +10:00
feature-fixups.c	powerpc: Use WARN_ON(1) instead of __WARN()	2008-07-22 10:39:34 +10:00
locks.c
Makefile	powerpc/ppc32: static ftrace fixes for PPC32	2008-11-28 14:08:07 +01:00
mem_64.S
memcpy_64.S	powerpc: Fix 64bit memcpy() regression	2009-02-26 14:02:53 +11:00
rheap.c	powerpc: Fix corruption error in rh_alloc_fixed()	2008-12-17 10:06:14 -06:00
sstep.c	powerpc: Don't emulate mr. instructions	2009-02-10 14:39:07 +11:00
string.S	powerpc: Use PPC_LONG and PPC_LONG_ALIGN in lib/string.S	2008-07-22 10:39:35 +10:00
usercopy_64.c