From: Linus Torvalds Date: Fri, 20 Jun 2008 19:19:28 +0000 (-0700) Subject: [watchdog] hpwdt: fix use of inline assembly X-Git-Tag: v2.6.26-rc7~11 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=1f6ef2342972dc7fd623f360f84006e2304eb935;p=linux-2.6-omap-h63xx.git [watchdog] hpwdt: fix use of inline assembly The inline assembly in drivers/watchdog/hpwdt.c was incredibly broken, and included all the function prologue and epilogue stuff, even though it was itself then inside a C function where the compiler would add its own prologue and epilogue on top of it all. This then just _happened_ to work if you had exactly the right compiler version and exactly the right compiler flags, so that gcc just happened to not create any prologue at all (the gcc-generated epilogue wouldn't matter, since it would never be reached). But the more proper way to fix it is to simply not do this. Move the inline asm to the top level, with no surrounding function at all (the better alternative would be to remove the prologue and make it actually use proper description of the arguments to the inline asm, but that's a bigger change than the one I'm willing to make right now). Tested-by: S.Çağlar Onur Acked-by: Thomas Mingarelli Signed-off-by: Linus Torvalds --- diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c index 2686f3eaeed..eaa3f2a79ff 100644 --- a/drivers/watchdog/hpwdt.c +++ b/drivers/watchdog/hpwdt.c @@ -140,49 +140,53 @@ static struct pci_device_id hpwdt_devices[] = { }; MODULE_DEVICE_TABLE(pci, hpwdt_devices); +extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry); + #ifndef CONFIG_X86_64 /* --32 Bit Bios------------------------------------------------------------ */ #define HPWDT_ARCH 32 -asmlinkage void asminline_call(struct cmn_registers *pi86Regs, - unsigned long *pRomEntry) -{ - asm("pushl %ebp \n\t" - "movl %esp, %ebp \n\t" - "pusha \n\t" - "pushf \n\t" - "push %es \n\t" - "push %ds \n\t" - "pop %es \n\t" - "movl 8(%ebp),%eax \n\t" - "movl 4(%eax),%ebx \n\t" - "movl 8(%eax),%ecx \n\t" - "movl 12(%eax),%edx \n\t" - "movl 16(%eax),%esi \n\t" - "movl 20(%eax),%edi \n\t" - "movl (%eax),%eax \n\t" - "push %cs \n\t" - "call *12(%ebp) \n\t" - "pushf \n\t" - "pushl %eax \n\t" - "movl 8(%ebp),%eax \n\t" - "movl %ebx,4(%eax) \n\t" - "movl %ecx,8(%eax) \n\t" - "movl %edx,12(%eax) \n\t" - "movl %esi,16(%eax) \n\t" - "movl %edi,20(%eax) \n\t" - "movw %ds,24(%eax) \n\t" - "movw %es,26(%eax) \n\t" - "popl %ebx \n\t" - "movl %ebx,(%eax) \n\t" - "popl %ebx \n\t" - "movl %ebx,28(%eax) \n\t" - "pop %es \n\t" - "popf \n\t" - "popa \n\t" - "leave \n\t" "ret"); -} +asm(".text \n\t" + ".align 4 \n" + "asminline_call: \n\t" + "pushl %ebp \n\t" + "movl %esp, %ebp \n\t" + "pusha \n\t" + "pushf \n\t" + "push %es \n\t" + "push %ds \n\t" + "pop %es \n\t" + "movl 8(%ebp),%eax \n\t" + "movl 4(%eax),%ebx \n\t" + "movl 8(%eax),%ecx \n\t" + "movl 12(%eax),%edx \n\t" + "movl 16(%eax),%esi \n\t" + "movl 20(%eax),%edi \n\t" + "movl (%eax),%eax \n\t" + "push %cs \n\t" + "call *12(%ebp) \n\t" + "pushf \n\t" + "pushl %eax \n\t" + "movl 8(%ebp),%eax \n\t" + "movl %ebx,4(%eax) \n\t" + "movl %ecx,8(%eax) \n\t" + "movl %edx,12(%eax) \n\t" + "movl %esi,16(%eax) \n\t" + "movl %edi,20(%eax) \n\t" + "movw %ds,24(%eax) \n\t" + "movw %es,26(%eax) \n\t" + "popl %ebx \n\t" + "movl %ebx,(%eax) \n\t" + "popl %ebx \n\t" + "movl %ebx,28(%eax) \n\t" + "pop %es \n\t" + "popf \n\t" + "popa \n\t" + "leave \n\t" + "ret \n\t" + ".previous"); + /* * cru_detect @@ -333,43 +337,44 @@ static int __devinit detect_cru_service(void) #define HPWDT_ARCH 64 -asmlinkage void asminline_call(struct cmn_registers *pi86Regs, - unsigned long *pRomEntry) -{ - asm("pushq %rbp \n\t" - "movq %rsp, %rbp \n\t" - "pushq %rax \n\t" - "pushq %rbx \n\t" - "pushq %rdx \n\t" - "pushq %r12 \n\t" - "pushq %r9 \n\t" - "movq %rsi, %r12 \n\t" - "movq %rdi, %r9 \n\t" - "movl 4(%r9),%ebx \n\t" - "movl 8(%r9),%ecx \n\t" - "movl 12(%r9),%edx \n\t" - "movl 16(%r9),%esi \n\t" - "movl 20(%r9),%edi \n\t" - "movl (%r9),%eax \n\t" - "call *%r12 \n\t" - "pushfq \n\t" - "popq %r12 \n\t" - "popfq \n\t" - "movl %eax, (%r9) \n\t" - "movl %ebx, 4(%r9) \n\t" - "movl %ecx, 8(%r9) \n\t" - "movl %edx, 12(%r9) \n\t" - "movl %esi, 16(%r9) \n\t" - "movl %edi, 20(%r9) \n\t" - "movq %r12, %rax \n\t" - "movl %eax, 28(%r9) \n\t" - "popq %r9 \n\t" - "popq %r12 \n\t" - "popq %rdx \n\t" - "popq %rbx \n\t" - "popq %rax \n\t" - "leave \n\t" "ret"); -} +asm(".text \n\t" + ".align 4 \n" + "asminline_call: \n\t" + "pushq %rbp \n\t" + "movq %rsp, %rbp \n\t" + "pushq %rax \n\t" + "pushq %rbx \n\t" + "pushq %rdx \n\t" + "pushq %r12 \n\t" + "pushq %r9 \n\t" + "movq %rsi, %r12 \n\t" + "movq %rdi, %r9 \n\t" + "movl 4(%r9),%ebx \n\t" + "movl 8(%r9),%ecx \n\t" + "movl 12(%r9),%edx \n\t" + "movl 16(%r9),%esi \n\t" + "movl 20(%r9),%edi \n\t" + "movl (%r9),%eax \n\t" + "call *%r12 \n\t" + "pushfq \n\t" + "popq %r12 \n\t" + "popfq \n\t" + "movl %eax, (%r9) \n\t" + "movl %ebx, 4(%r9) \n\t" + "movl %ecx, 8(%r9) \n\t" + "movl %edx, 12(%r9) \n\t" + "movl %esi, 16(%r9) \n\t" + "movl %edi, 20(%r9) \n\t" + "movq %r12, %rax \n\t" + "movl %eax, 28(%r9) \n\t" + "popq %r9 \n\t" + "popq %r12 \n\t" + "popq %rdx \n\t" + "popq %rbx \n\t" + "popq %rax \n\t" + "leave \n\t" + "ret \n\t" + ".previous"); /* * dmi_find_cru