| From | Paul Gortmaker <> | Subject | [34-longterm 139/247] x86: Use u32 instead of long to set reset vector back to 0 | Date | Thu, 23 Jun 2011 13:33:27 -0400 |
| |
From: Don Zickus <dzickus@redhat.com>
------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. -------------------
commit 299c56966a72b9109d47c71a6db52097098703dd upstream.
A customer of ours, complained that when setting the reset vector back to 0, it trashed other data and hung their box. They noticed when only 4 bytes were set to 0 instead of 8, everything worked correctly.
Mathew pointed out:
| | We're supposed to be resetting trampoline_phys_low and | trampoline_phys_high here, which are two 16-bit values. | Writing 64 bits is definitely going to overwrite space | that we're not supposed to be touching. |
So limit the area modified to u32.
Signed-off-by: Don Zickus <dzickus@redhat.com> Acked-by: Matthew Garrett <mjg@redhat.com> LKML-Reference: <1297139100-424-1-git-send-email-dzickus@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> --- arch/x86/include/asm/smpboot_hooks.h | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/x86/include/asm/smpboot_hooks.h b/arch/x86/include/asm/smpboot_hooks.h index 1def601..cfdc6c8 100644 --- a/arch/x86/include/asm/smpboot_hooks.h +++ b/arch/x86/include/asm/smpboot_hooks.h @@ -34,7 +34,7 @@ static inline void smpboot_restore_warm_reset_vector(void) */ CMOS_WRITE(0, 0xf); - *((volatile long *)phys_to_virt(apic->trampoline_phys_low)) = 0; + *((volatile u32 *)phys_to_virt(apic->trampoline_phys_low)) = 0; } static inline void __init smpboot_setup_io_apic(void) -- 1.7.4.4
|