| Message ID | e520030f750b29d14486aa1e99c271a0fa18f19e.1453759363.git.luto@kernel.org |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
From: Andy Lutomirski <luto@kernel.org> Date: Mon, 25 Jan 2016 14:24:16 -0800 > On sparc64 compat-enabled kernels, any task can make 32-bit and > 64-bit syscalls. is_compat_task returns true in 32-bit tasks, which > does not necessarily imply that the current syscall is 32-bit. > > Provide an in_compat_syscall implementation that checks whether the > current syscall is compat. > > As far as I know, sparc is the only architecture on which > is_compat_task checks the compat status of the task and on which the > compat status of a syscall can differ from the compat status of the > task. On x86, is_compat_task checks the syscall type, not the task > type. > > Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Jan 25, 2016 at 02:24:16PM -0800, Andy Lutomirski wrote: > On sparc64 compat-enabled kernels, any task can make 32-bit and > 64-bit syscalls. is_compat_task returns true in 32-bit tasks, which > does not necessarily imply that the current syscall is 32-bit. > > Provide an in_compat_syscall implementation that checks whether the > current syscall is compat. > > As far as I know, sparc is the only architecture on which > is_compat_task checks the compat status of the task and on which the > compat status of a syscall can differ from the compat status of the > task. On x86, is_compat_task checks the syscall type, not the task > type. > > Signed-off-by: Andy Lutomirski <luto@kernel.org> > --- > arch/sparc/include/asm/compat.h | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h > index 830502fe62b4..5467404857fc 100644 > --- a/arch/sparc/include/asm/compat.h > +++ b/arch/sparc/include/asm/compat.h > @@ -307,4 +307,10 @@ static inline int is_compat_task(void) > return test_thread_flag(TIF_32BIT); > } > > +static inline bool in_compat_syscall(void) > +{ > + return pt_regs_trap_type(current_pt_regs()) == 0x110; Could you please add a comment about where 0x110 comes from. I at least failed to track this down. Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Sam Ravnborg <sam@ravnborg.org> Date: Tue, 26 Jan 2016 07:29:51 +0100 > Could you please add a comment about where 0x110 comes from. > I at least failed to track this down. Frankly I'm fine with this. Someone who understands sparc64 can look at the trap table around entry 0x110 and see: tl0_resv10e: BTRAP(0x10e) BTRAP(0x10f) tl0_linux32: LINUX_32BIT_SYSCALL_TRAP tl0_oldlinux64: LINUX_64BIT_SYSCALL_TRAP -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Jan 25, 2016 at 10:51:00PM -0800, David Miller wrote: > From: Sam Ravnborg <sam@ravnborg.org> > Date: Tue, 26 Jan 2016 07:29:51 +0100 > > > Could you please add a comment about where 0x110 comes from. > > I at least failed to track this down. > > Frankly I'm fine with this. Someone who understands sparc64 can look > at the trap table around entry 0x110 and see: > > tl0_resv10e: BTRAP(0x10e) BTRAP(0x10f) > tl0_linux32: LINUX_32BIT_SYSCALL_TRAP > tl0_oldlinux64: LINUX_64BIT_SYSCALL_TRAP If one realise to look in the trap table in the first place - yes. Adding a short: /* Check if this is LINUX_32BIT_SYSCALL_TRAP */ Would make wonders to readability. Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jan 26, 2016 at 9:44 AM, Sam Ravnborg <sam@ravnborg.org> wrote: > On Mon, Jan 25, 2016 at 10:51:00PM -0800, David Miller wrote: >> From: Sam Ravnborg <sam@ravnborg.org> >> Date: Tue, 26 Jan 2016 07:29:51 +0100 >> >> > Could you please add a comment about where 0x110 comes from. >> > I at least failed to track this down. >> >> Frankly I'm fine with this. Someone who understands sparc64 can look >> at the trap table around entry 0x110 and see: >> >> tl0_resv10e: BTRAP(0x10e) BTRAP(0x10f) >> tl0_linux32: LINUX_32BIT_SYSCALL_TRAP >> tl0_oldlinux64: LINUX_64BIT_SYSCALL_TRAP > > If one realise to look in the trap table in the first place - yes. > > Adding a short: > > /* Check if this is LINUX_32BIT_SYSCALL_TRAP */ > Would make wonders to readability. I'll add a comment in v2. --Andy
From: Sam Ravnborg <sam@ravnborg.org> Date: Tue, 26 Jan 2016 18:44:41 +0100 > On Mon, Jan 25, 2016 at 10:51:00PM -0800, David Miller wrote: >> From: Sam Ravnborg <sam@ravnborg.org> >> Date: Tue, 26 Jan 2016 07:29:51 +0100 >> >> > Could you please add a comment about where 0x110 comes from. >> > I at least failed to track this down. >> >> Frankly I'm fine with this. Someone who understands sparc64 can look >> at the trap table around entry 0x110 and see: >> >> tl0_resv10e: BTRAP(0x10e) BTRAP(0x10f) >> tl0_linux32: LINUX_32BIT_SYSCALL_TRAP >> tl0_oldlinux64: LINUX_64BIT_SYSCALL_TRAP > > If one realise to look in the trap table in the first place - yes. > > Adding a short: > > /* Check if this is LINUX_32BIT_SYSCALL_TRAP */ > Would make wonders to readability. Fair enough. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h index 830502fe62b4..5467404857fc 100644 --- a/arch/sparc/include/asm/compat.h +++ b/arch/sparc/include/asm/compat.h @@ -307,4 +307,10 @@ static inline int is_compat_task(void) return test_thread_flag(TIF_32BIT); } +static inline bool in_compat_syscall(void) +{ + return pt_regs_trap_type(current_pt_regs()) == 0x110; +} +#define in_compat_syscall in_compat_syscall + #endif /* _ASM_SPARC64_COMPAT_H */
On sparc64 compat-enabled kernels, any task can make 32-bit and 64-bit syscalls. is_compat_task returns true in 32-bit tasks, which does not necessarily imply that the current syscall is 32-bit. Provide an in_compat_syscall implementation that checks whether the current syscall is compat. As far as I know, sparc is the only architecture on which is_compat_task checks the compat status of the task and on which the compat status of a syscall can differ from the compat status of the task. On x86, is_compat_task checks the syscall type, not the task type. Signed-off-by: Andy Lutomirski <luto@kernel.org> --- arch/sparc/include/asm/compat.h | 6 ++++++ 1 file changed, 6 insertions(+)