under paravirt, read cr2 cannot be issued directly anymore. So wrap it in a macro, defined to the operation itself in case paravirt is off, but to something else if we have paravirt in the game Signed-off-by: Glauber de Oliveira Costa <gcosta@xxxxxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- arch/x86_64/kernel/head.S | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S index e89abcd..1bb6c55 100644 --- a/arch/x86_64/kernel/head.S +++ b/arch/x86_64/kernel/head.S @@ -18,6 +18,12 @@ #include <asm/page.h> #include <asm/msr.h> #include <asm/cache.h> +#ifdef CONFIG_PARAVIRT +#include <asm/asm-offsets.h> +#include <asm/paravirt.h> +#else +#define GET_CR2_INTO_RCX mov %cr2, %rcx +#endif /* we are not able to switch in one step to the final KERNEL ADRESS SPACE * because we need identity-mapped pages. @@ -267,7 +273,9 @@ ENTRY(early_idt_handler) xorl %eax,%eax movq 8(%rsp),%rsi # get rip movq (%rsp),%rdx - movq %cr2,%rcx + /* When PARAVIRT is on, this operation may clobber rax. It is + something safe to do, because we've just zeroed rax. */ + GET_CR2_INTO_RCX leaq early_idt_msg(%rip),%rdi call early_printk cmpl $2,early_recursion_flag(%rip) -- 1.4.4.2 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
