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| author |   Tejun Heo <tj@kernel.org> | 2009-02-09 22:17:39 +0900 |
|---|---|---|
| committer |   Ingo Molnar <mingo@elte.hu> | 2009-02-10 00:39:14 +0100 |
| commit | d315760ffa261c15ff92699ac6f514112543d7ca (patch) | |
| tree | 3f7d185cf97a06e6686521a23a1c78d1809a51c4 /arch/x86/math-emu/fpu_system.h | |
| parent | x86: math_emu info cleanup (diff) | |
| download | linux-dev-d315760ffa261c15ff92699ac6f514112543d7ca.tar.xz linux-dev-d315760ffa261c15ff92699ac6f514112543d7ca.zip | |
x86: fix math_emu register frame access
do_device_not_available() is the handler for #NM and it declares that
it takes a unsigned long and calls math_emu(), which takes a long
argument and surprisingly expects the stack frame starting at the zero
argument would match struct math_emu_info, which isn't true regardless
of configuration in the current code.
This patch makes do_device_not_available() take struct pt_regs like
other exception handlers and initialize struct math_emu_info with
pointer to it and pass pointer to the math_emu_info to math_emulate()
like normal C functions do. This way, unless gcc makes a copy of
struct pt_regs in do_device_not_available(), the register frame is
correctly accessed regardless of kernel configuration or compiler
used.
This doesn't fix all math_emu problems but it at least gets it
somewhat working.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/math-emu/fpu_system.h')
| -rw-r--r-- | arch/x86/math-emu/fpu_system.h | 16 |
1 files changed, 6 insertions, 10 deletions
diff --git a/arch/x86/math-emu/fpu_system.h b/arch/x86/math-emu/fpu_system.h index 6729c6a31348..50fa0ec2c8a5 100644 --- a/arch/x86/math-emu/fpu_system.h +++ b/arch/x86/math-emu/fpu_system.h @@ -16,10 +16,6 @@ #include <linux/kernel.h> #include <linux/mm.h> -/* This sets the pointer FPU_info to point to the argument part - of the stack frame of math_emulate() */ -#define SETUP_DATA_AREA(arg) FPU_info = (struct math_emu_info *) &arg - /* s is always from a cpu register, and the cpu does bounds checking * during register load --> no further bounds checks needed */ #define LDT_DESCRIPTOR(s) (((struct desc_struct *)current->mm->context.ldt)[(s) >> 3]) @@ -38,12 +34,12 @@ #define I387 (current->thread.xstate) #define FPU_info (I387->soft.info) -#define FPU_CS (*(unsigned short *) &(FPU_info->regs.cs)) -#define FPU_SS (*(unsigned short *) &(FPU_info->regs.ss)) -#define FPU_DS (*(unsigned short *) &(FPU_info->regs.ds)) -#define FPU_EAX (FPU_info->regs.ax) -#define FPU_EFLAGS (FPU_info->regs.flags) -#define FPU_EIP (FPU_info->regs.ip) +#define FPU_CS (*(unsigned short *) &(FPU_info->regs->cs)) +#define FPU_SS (*(unsigned short *) &(FPU_info->regs->ss)) +#define FPU_DS (*(unsigned short *) &(FPU_info->regs->ds)) +#define FPU_EAX (FPU_info->regs->ax) +#define FPU_EFLAGS (FPU_info->regs->flags) +#define FPU_EIP (FPU_info->regs->ip) #define FPU_ORIG_EIP (FPU_info->___orig_eip) #define FPU_lookahead (I387->soft.lookahead) |