EFER varies like %cr4 depending on the cpu capabilities, and which cpu capabilities we want to make use of. So save/restore it make certain we have the same EFER value when we are done.
Signed-off-by: Eric W. Biederman <[EMAIL PROTECTED]> Signed-off-by: Vivek Goyal <[EMAIL PROTECTED]> --- arch/x86_64/kernel/suspend.c | 3 ++- include/asm-x86_64/suspend.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff -puN arch/x86_64/kernel/suspend.c~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state arch/x86_64/kernel/suspend.c --- linux-2.6.19-rc6-reloc/arch/x86_64/kernel/suspend.c~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state 2006-11-17 00:08:16.000000000 -0500 +++ linux-2.6.19-rc6-reloc-root/arch/x86_64/kernel/suspend.c 2006-11-17 00:08:16.000000000 -0500 @@ -33,7 +33,6 @@ void __save_processor_state(struct saved asm volatile ("str %0" : "=m" (ctxt->tr)); /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ - /* EFER should be constant for kernel version, no need to handle it. */ /* * segment registers */ @@ -50,6 +49,7 @@ void __save_processor_state(struct saved /* * control registers */ + rdmsrl(MSR_EFER, ctxt->efer); asm volatile ("movq %%cr0, %0" : "=r" (ctxt->cr0)); asm volatile ("movq %%cr2, %0" : "=r" (ctxt->cr2)); asm volatile ("movq %%cr3, %0" : "=r" (ctxt->cr3)); @@ -75,6 +75,7 @@ void __restore_processor_state(struct sa /* * control registers */ + wrmsrl(MSR_EFER, ctxt->efer); asm volatile ("movq %0, %%cr8" :: "r" (ctxt->cr8)); asm volatile ("movq %0, %%cr4" :: "r" (ctxt->cr4)); asm volatile ("movq %0, %%cr3" :: "r" (ctxt->cr3)); diff -puN include/asm-x86_64/suspend.h~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state include/asm-x86_64/suspend.h --- linux-2.6.19-rc6-reloc/include/asm-x86_64/suspend.h~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state 2006-11-17 00:08:16.000000000 -0500 +++ linux-2.6.19-rc6-reloc-root/include/asm-x86_64/suspend.h 2006-11-17 00:08:16.000000000 -0500 @@ -17,6 +17,7 @@ struct saved_context { u16 ds, es, fs, gs, ss; unsigned long gs_base, gs_kernel_base, fs_base; unsigned long cr0, cr2, cr3, cr4, cr8; + unsigned long efer; u16 gdt_pad; u16 gdt_limit; unsigned long gdt_base; _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/