| Message ID | 1347557866-7256-2-git-send-email-sw@weilnetz.de |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, Sep 13, 2012 at 07:37:43PM +0200, Stefan Weil wrote: > TCG uses 6 registers for function arguments on 64 bit Linux hosts, > but only 4 registers on W64 hosts. > > Commit 2999a0b20074a7e4a58f56572bb1436749368f59 increased the number > of arguments for some important helper functions from 4 to 5 > which triggered a bug for W64 hosts: QEMU aborts when executing > helper_lcall_real in the guest's BIOS because function > tcg_target_get_call_iarg_regs_count always returned 6. > > As W64 has only 4 registers for arguments, the 5th argument must be > passed on the stack using a correct stack offset. > > Signed-off-by: Stefan Weil <sw@weilnetz.de> > --- > tcg/i386/tcg-target.c | 2 +- > tcg/i386/tcg-target.h | 4 ++++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c > index da17bba..43b5572 100644 > --- a/tcg/i386/tcg-target.c > +++ b/tcg/i386/tcg-target.c > @@ -118,7 +118,7 @@ static void patch_reloc(uint8_t *code_ptr, int type, > static inline int tcg_target_get_call_iarg_regs_count(int flags) > { > if (TCG_TARGET_REG_BITS == 64) { > - return 6; > + return ARRAY_SIZE(tcg_target_call_iarg_regs); > } > > return 0; > diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h > index c3cfe05..87417d0 100644 > --- a/tcg/i386/tcg-target.h > +++ b/tcg/i386/tcg-target.h > @@ -67,7 +67,11 @@ typedef enum { > /* used for function call generation */ > #define TCG_REG_CALL_STACK TCG_REG_ESP > #define TCG_TARGET_STACK_ALIGN 16 > +#if defined(_WIN64) > +#define TCG_TARGET_CALL_STACK_OFFSET 32 > +#else > #define TCG_TARGET_CALL_STACK_OFFSET 0 > +#endif > > /* optional instructions */ > #define TCG_TARGET_HAS_div2_i32 1 > -- > 1.7.10 > > Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
On Thu, Sep 13, 2012 at 07:37:43PM +0200, Stefan Weil wrote: > TCG uses 6 registers for function arguments on 64 bit Linux hosts, > but only 4 registers on W64 hosts. > > Commit 2999a0b20074a7e4a58f56572bb1436749368f59 increased the number > of arguments for some important helper functions from 4 to 5 > which triggered a bug for W64 hosts: QEMU aborts when executing > helper_lcall_real in the guest's BIOS because function > tcg_target_get_call_iarg_regs_count always returned 6. > > As W64 has only 4 registers for arguments, the 5th argument must be > passed on the stack using a correct stack offset. > > Signed-off-by: Stefan Weil <sw@weilnetz.de> > --- > tcg/i386/tcg-target.c | 2 +- > tcg/i386/tcg-target.h | 4 ++++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c > index da17bba..43b5572 100644 > --- a/tcg/i386/tcg-target.c > +++ b/tcg/i386/tcg-target.c > @@ -118,7 +118,7 @@ static void patch_reloc(uint8_t *code_ptr, int type, > static inline int tcg_target_get_call_iarg_regs_count(int flags) > { > if (TCG_TARGET_REG_BITS == 64) { > - return 6; > + return ARRAY_SIZE(tcg_target_call_iarg_regs); > } > > return 0; > diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h > index c3cfe05..87417d0 100644 > --- a/tcg/i386/tcg-target.h > +++ b/tcg/i386/tcg-target.h > @@ -67,7 +67,11 @@ typedef enum { > /* used for function call generation */ > #define TCG_REG_CALL_STACK TCG_REG_ESP > #define TCG_TARGET_STACK_ALIGN 16 > +#if defined(_WIN64) > +#define TCG_TARGET_CALL_STACK_OFFSET 32 > +#else > #define TCG_TARGET_CALL_STACK_OFFSET 0 > +#endif > > /* optional instructions */ > #define TCG_TARGET_HAS_div2_i32 1 > -- > 1.7.10 > > Thanks, applied.
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c index da17bba..43b5572 100644 --- a/tcg/i386/tcg-target.c +++ b/tcg/i386/tcg-target.c @@ -118,7 +118,7 @@ static void patch_reloc(uint8_t *code_ptr, int type, static inline int tcg_target_get_call_iarg_regs_count(int flags) { if (TCG_TARGET_REG_BITS == 64) { - return 6; + return ARRAY_SIZE(tcg_target_call_iarg_regs); } return 0; diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h index c3cfe05..87417d0 100644 --- a/tcg/i386/tcg-target.h +++ b/tcg/i386/tcg-target.h @@ -67,7 +67,11 @@ typedef enum { /* used for function call generation */ #define TCG_REG_CALL_STACK TCG_REG_ESP #define TCG_TARGET_STACK_ALIGN 16 +#if defined(_WIN64) +#define TCG_TARGET_CALL_STACK_OFFSET 32 +#else #define TCG_TARGET_CALL_STACK_OFFSET 0 +#endif /* optional instructions */ #define TCG_TARGET_HAS_div2_i32 1
TCG uses 6 registers for function arguments on 64 bit Linux hosts, but only 4 registers on W64 hosts. Commit 2999a0b20074a7e4a58f56572bb1436749368f59 increased the number of arguments for some important helper functions from 4 to 5 which triggered a bug for W64 hosts: QEMU aborts when executing helper_lcall_real in the guest's BIOS because function tcg_target_get_call_iarg_regs_count always returned 6. As W64 has only 4 registers for arguments, the 5th argument must be passed on the stack using a correct stack offset. Signed-off-by: Stefan Weil <sw@weilnetz.de> --- tcg/i386/tcg-target.c | 2 +- tcg/i386/tcg-target.h | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-)