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| author | Vivek Goyal <vgoyal@in.ibm.com> | 2007-05-02 21:27:08 +0400 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2007-05-02 21:27:08 +0400 |
| commit | 6a50a664ca0cfd2a487525f10cec3ff4d570b5e8 (patch) | |
| tree | cf68fae284a7b44df616a8112e9088557ad31d76 /arch/x86_64/boot/compressed/misc.c | |
| parent | 1ab60e0f72f71ec54831e525a3e1154f1c092408 (diff) | |
| download | linux-6a50a664ca0cfd2a487525f10cec3ff4d570b5e8.tar.xz | |
[PATCH] x86-64: build-time checking
o X86_64 kernel should run from 2MB aligned address for two reasons.
- Performance.
- For relocatable kernels, page tables are updated based on difference
between compile time address and load time physical address.
This difference should be multiple of 2MB as kernel text and data
is mapped using 2MB pages and PMD should be pointing to a 2MB
aligned address. Life is simpler if both compile time and load time
kernel addresses are 2MB aligned.
o Flag the error at compile time if one is trying to build a kernel which
does not meet alignment restrictions.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/x86_64/boot/compressed/misc.c')
| -rw-r--r-- | arch/x86_64/boot/compressed/misc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86_64/boot/compressed/misc.c b/arch/x86_64/boot/compressed/misc.c index fee54dbf1749..fed1167159c3 100644 --- a/arch/x86_64/boot/compressed/misc.c +++ b/arch/x86_64/boot/compressed/misc.c @@ -358,7 +358,7 @@ asmlinkage void decompress_kernel(void *rmode, unsigned long heap, insize = input_len; inptr = 0; - if ((ulg)output & 0x1fffffUL) + if ((ulg)output & (__KERNEL_ALIGN - 1)) error("Destination address not 2M aligned"); if ((ulg)output >= 0xffffffffffUL) error("Destination address too large"); |