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authorYinghai Lu2009-05-06 21:36:16 -0700
committerIngo Molnar2009-05-11 11:40:43 +0200
commit917a0153621572e88aeb2d5df025ad2e81027287 (patch)
tree4a1f06f9820f10d714814a9fa86f2094e8eb9c4a /arch/x86/kernel
parentb74d446f1f337e3fe906169a3266cb65ffa4179e (diff)
x86: mtrr: Fix high_width computation when phys-addr is >= 44bit
found one system where cpu address line is 44bits, mtrr printout is not right: [ 0.000000] MTRR variable ranges enabled: [ 0.000000] 0 base 0 00000000 mask FF0 00000000 write-back [ 0.000000] 1 base 10 00000000 mask FFF 80000000 write-back [ 0.000000] 2 base 0 80000000 mask FFF 80000000 uncachable [ 0.000000] 3 base 0 7F800000 mask FFF FF800000 uncachable Li Zefan and Frederic pointed out the high_width could be -4 some how. It turns out when phys_addr is 44bit, size_or_mask will be ffffffff,00000000 so ffs(size_or_mask) will be 0. Try to check low 32 bit, to get correct high_width. Signed-off-by: Yinghai Lu <yinghai@kerne.org> Also-analyzed-by: Frederic Weisbecker <fweisbec@gmail.com> Also-analyzed-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Zhaolei <zhaolei@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <4A026540.8060504@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
index 0b776c09aff3..d21d4fb161f7 100644
--- a/arch/x86/kernel/cpu/mtrr/generic.c
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -275,7 +275,11 @@ static void __init print_mtrr_state(void)
}
printk(KERN_DEBUG "MTRR variable ranges %sabled:\n",
mtrr_state.enabled & 2 ? "en" : "dis");
- high_width = ((size_or_mask ? ffs(size_or_mask) - 1 : 32) - (32 - PAGE_SHIFT) + 3) / 4;
+ if (size_or_mask & 0xffffffffUL)
+ high_width = ffs(size_or_mask & 0xffffffffUL) - 1;
+ else
+ high_width = ffs(size_or_mask>>32) + 32 - 1;
+ high_width = (high_width - (32 - PAGE_SHIFT) + 3) / 4;
for (i = 0; i < num_var_ranges; ++i) {
if (mtrr_state.var_ranges[i].mask_lo & (1 << 11))
printk(KERN_DEBUG " %u base %0*X%05X000 mask %0*X%05X000 %s\n",