From 0e861fbb5bda79b871341ef2a9a8059765cbe8a4 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 2 Apr 2016 07:01:34 -0700 Subject: x86/head: Move early exception panic code into early_fixup_exception() This removes a bunch of assembly and adds some C code instead. It changes the actual printouts on both 32-bit and 64-bit kernels, but they still seem okay. Tested-by: Boris Ostrovsky Signed-off-by: Andy Lutomirski Acked-by: Linus Torvalds Cc: Andrew Morton Cc: Arjan van de Ven Cc: Borislav Petkov Cc: KVM list Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: xen-devel Link: http://lkml.kernel.org/r/4085070316fc3ab29538d3fcfe282648d1d4ee2e.1459605520.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/head_64.S | 45 ++------------------------------------------- 1 file changed, 2 insertions(+), 43 deletions(-) (limited to 'arch/x86/kernel/head_64.S') diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 2308437..3de91a7 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -351,8 +351,6 @@ early_idt_handler_common: */ cld - cmpl $2,early_recursion_flag(%rip) - jz 1f incl early_recursion_flag(%rip) /* The vector number is currently in the pt_regs->di slot. */ @@ -373,9 +371,6 @@ early_idt_handler_common: pushq %r14 /* pt_regs->r14 */ pushq %r15 /* pt_regs->r15 */ - cmpl $__KERNEL_CS,CS(%rsp) - jne 11f - cmpq $14,%rsi /* Page fault? */ jnz 10f GET_CR2_INTO(%rdi) /* Can clobber any volatile register if pv */ @@ -386,37 +381,8 @@ early_idt_handler_common: 10: movq %rsp,%rdi /* RDI = pt_regs; RSI is already trapnr */ call early_fixup_exception - andl %eax,%eax - jnz 20f # Found an exception entry - -11: -#ifdef CONFIG_EARLY_PRINTK - /* - * On paravirt kernels, GET_CR2_INTO clobbers callee-clobbered regs. - * We only care about RSI, so we need to save it. - */ - movq %rsi,%rbx /* Save vector number */ - GET_CR2_INTO(%r9) - movq ORIG_RAX(%rsp),%r8 /* error code */ - movq %rbx,%rsi /* vector number */ - movq CS(%rsp),%rdx - movq RIP(%rsp),%rcx - xorl %eax,%eax - leaq early_idt_msg(%rip),%rdi - call early_printk - cmpl $2,early_recursion_flag(%rip) - jz 1f - call dump_stack -#ifdef CONFIG_KALLSYMS - leaq early_idt_ripmsg(%rip),%rdi - movq RIP(%rsp),%rsi # %rip again - call __print_symbol -#endif -#endif /* EARLY_PRINTK */ -1: hlt - jmp 1b -20: /* Exception table entry found or page table generated */ +20: decl early_recursion_flag(%rip) jmp restore_regs_and_iret ENDPROC(early_idt_handler_common) @@ -424,16 +390,9 @@ ENDPROC(early_idt_handler_common) __INITDATA .balign 4 -early_recursion_flag: +GLOBAL(early_recursion_flag) .long 0 -#ifdef CONFIG_EARLY_PRINTK -early_idt_msg: - .asciz "PANIC: early exception %02lx rip %lx:%lx error %lx cr2 %lx\n" -early_idt_ripmsg: - .asciz "RIP %s\n" -#endif /* CONFIG_EARLY_PRINTK */ - #define NEXT_PAGE(name) \ .balign PAGE_SIZE; \ GLOBAL(name) -- cgit v1.1