Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
[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 <caglar@pardus.org.tr>
Acked-by: Thomas Mingarelli <Thomas.Mingarelli@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+80
-75
drivers/watchdog/hpwdt.c
+80
-75
drivers/watchdog/hpwdt.c
···
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};
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MODULE_DEVICE_TABLE(pci, hpwdt_devices);
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extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry);
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#ifndef CONFIG_X86_64
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/* --32 Bit Bios------------------------------------------------------------ */
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#define HPWDT_ARCH 32
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asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
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unsigned long *pRomEntry)
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{
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asm("pushl %ebp \n\t"
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-
"movl %esp, %ebp \n\t"
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-
"pusha \n\t"
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-
"pushf \n\t"
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-
"push %es \n\t"
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"push %ds \n\t"
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"pop %es \n\t"
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"movl 8(%ebp),%eax \n\t"
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-
"movl 4(%eax),%ebx \n\t"
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-
"movl 8(%eax),%ecx \n\t"
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-
"movl 12(%eax),%edx \n\t"
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-
"movl 16(%eax),%esi \n\t"
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-
"movl 20(%eax),%edi \n\t"
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-
"movl (%eax),%eax \n\t"
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-
"push %cs \n\t"
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"call *12(%ebp) \n\t"
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-
"pushf \n\t"
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"pushl %eax \n\t"
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"movl 8(%ebp),%eax \n\t"
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"movl %ebx,4(%eax) \n\t"
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"movl %ecx,8(%eax) \n\t"
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"movl %edx,12(%eax) \n\t"
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"movl %esi,16(%eax) \n\t"
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"movl %edi,20(%eax) \n\t"
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"movw %ds,24(%eax) \n\t"
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"movw %es,26(%eax) \n\t"
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"popl %ebx \n\t"
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"movl %ebx,(%eax) \n\t"
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-
"popl %ebx \n\t"
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"movl %ebx,28(%eax) \n\t"
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"pop %es \n\t"
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"popf \n\t"
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"popa \n\t"
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-
"leave \n\t" "ret");
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-
}
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asm(".text \n\t"
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".align 4 \n"
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"asminline_call: \n\t"
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"pushl %ebp \n\t"
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"movl %esp, %ebp \n\t"
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"pusha \n\t"
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"pushf \n\t"
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"push %es \n\t"
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"push %ds \n\t"
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"pop %es \n\t"
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"movl 8(%ebp),%eax \n\t"
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"movl 4(%eax),%ebx \n\t"
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"movl 8(%eax),%ecx \n\t"
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"movl 12(%eax),%edx \n\t"
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"movl 16(%eax),%esi \n\t"
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"movl 20(%eax),%edi \n\t"
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"movl (%eax),%eax \n\t"
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+
"push %cs \n\t"
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"call *12(%ebp) \n\t"
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"pushf \n\t"
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"pushl %eax \n\t"
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"movl 8(%ebp),%eax \n\t"
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"movl %ebx,4(%eax) \n\t"
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+
"movl %ecx,8(%eax) \n\t"
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"movl %edx,12(%eax) \n\t"
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"movl %esi,16(%eax) \n\t"
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"movl %edi,20(%eax) \n\t"
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"movw %ds,24(%eax) \n\t"
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"movw %es,26(%eax) \n\t"
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"popl %ebx \n\t"
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"movl %ebx,(%eax) \n\t"
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"popl %ebx \n\t"
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"movl %ebx,28(%eax) \n\t"
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"pop %es \n\t"
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"popf \n\t"
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"popa \n\t"
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+
"leave \n\t"
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"ret \n\t"
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".previous");
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/*
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* cru_detect
···
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#define HPWDT_ARCH 64
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asmlinkage void asminline_call(struct cmn_registers *pi86Regs,
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unsigned long *pRomEntry)
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{
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asm("pushq %rbp \n\t"
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"movq %rsp, %rbp \n\t"
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-
"pushq %rax \n\t"
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-
"pushq %rbx \n\t"
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"pushq %rdx \n\t"
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-
"pushq %r12 \n\t"
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"pushq %r9 \n\t"
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"movq %rsi, %r12 \n\t"
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-
"movq %rdi, %r9 \n\t"
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"movl 4(%r9),%ebx \n\t"
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-
"movl 8(%r9),%ecx \n\t"
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"movl 12(%r9),%edx \n\t"
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"movl 16(%r9),%esi \n\t"
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-
"movl 20(%r9),%edi \n\t"
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-
"movl (%r9),%eax \n\t"
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-
"call *%r12 \n\t"
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"pushfq \n\t"
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"popq %r12 \n\t"
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"popfq \n\t"
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"movl %eax, (%r9) \n\t"
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"movl %ebx, 4(%r9) \n\t"
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"movl %ecx, 8(%r9) \n\t"
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"movl %edx, 12(%r9) \n\t"
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"movl %esi, 16(%r9) \n\t"
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"movl %edi, 20(%r9) \n\t"
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"movq %r12, %rax \n\t"
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-
"movl %eax, 28(%r9) \n\t"
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"popq %r9 \n\t"
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-
"popq %r12 \n\t"
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"popq %rdx \n\t"
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-
"popq %rbx \n\t"
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-
"popq %rax \n\t"
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-
"leave \n\t" "ret");
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-
}
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asm(".text \n\t"
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".align 4 \n"
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"asminline_call: \n\t"
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"pushq %rbp \n\t"
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"movq %rsp, %rbp \n\t"
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"pushq %rax \n\t"
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"pushq %rbx \n\t"
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"pushq %rdx \n\t"
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"pushq %r12 \n\t"
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"pushq %r9 \n\t"
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"movq %rsi, %r12 \n\t"
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"movq %rdi, %r9 \n\t"
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+
"movl 4(%r9),%ebx \n\t"
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+
"movl 8(%r9),%ecx \n\t"
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+
"movl 12(%r9),%edx \n\t"
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+
"movl 16(%r9),%esi \n\t"
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+
"movl 20(%r9),%edi \n\t"
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+
"movl (%r9),%eax \n\t"
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+
"call *%r12 \n\t"
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"pushfq \n\t"
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"popq %r12 \n\t"
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"popfq \n\t"
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"movl %eax, (%r9) \n\t"
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"movl %ebx, 4(%r9) \n\t"
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+
"movl %ecx, 8(%r9) \n\t"
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"movl %edx, 12(%r9) \n\t"
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"movl %esi, 16(%r9) \n\t"
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"movl %edi, 20(%r9) \n\t"
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"movq %r12, %rax \n\t"
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"movl %eax, 28(%r9) \n\t"
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"popq %r9 \n\t"
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"popq %r12 \n\t"
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"popq %rdx \n\t"
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"popq %rbx \n\t"
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"popq %rax \n\t"
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+
"leave \n\t"
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"ret \n\t"
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".previous");
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/*
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* dmi_find_cru