| Message ID | 20190916141544.17540-2-peter.maydell@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | target/arm: Implement semihosting v2.0 | expand |
On 9/16/19 4:15 PM, Peter Maydell wrote: > The set_swi_errno() function is called to capture the errno > from a host system call, so that we can return -1 from the > semihosting function and later allow the guest to get a more > specific error code with the SYS_ERRNO function. It comes in > two versions, one for user-only and one for softmmu. We forgot > to capture the errno in the softmmu version; fix the error. > > (Semihosting calls directed to gdb are unaffected because > they go through a different code path that captures the > error return from the gdbstub call in arm_semi_cb() or > arm_semi_flen_cb().) > Fixes: 8e71621f784 Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > NB that a later commit will put in some cleanup of TaskState > that will let us reduce the duplication between the two > implementations of this function. > --- > target/arm/arm-semi.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c > index 90423a35deb..03e60105c05 100644 > --- a/target/arm/arm-semi.c > +++ b/target/arm/arm-semi.c > @@ -114,8 +114,13 @@ static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code) > return code; > } > #else > +static target_ulong syscall_err; > + > static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code) > { > + if (code == (uint32_t)-1) { > + syscall_err = errno; > + } > return code; > } > > @@ -124,10 +129,6 @@ static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code) > > static target_ulong arm_semi_syscall_len; > > -#if !defined(CONFIG_USER_ONLY) > -static target_ulong syscall_err; > -#endif > - > static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err) > { > ARMCPU *cpu = ARM_CPU(cs); >
On Fri, 4 Oct 2019 at 00:24, Philippe Mathieu-Daudé <philmd@redhat.com> wrote: > > On 9/16/19 4:15 PM, Peter Maydell wrote: > > The set_swi_errno() function is called to capture the errno > > from a host system call, so that we can return -1 from the > > semihosting function and later allow the guest to get a more > > specific error code with the SYS_ERRNO function. It comes in > > two versions, one for user-only and one for softmmu. We forgot > > to capture the errno in the softmmu version; fix the error. > > > > (Semihosting calls directed to gdb are unaffected because > > they go through a different code path that captures the > > error return from the gdbstub call in arm_semi_cb() or > > arm_semi_flen_cb().) > > > > Fixes: 8e71621f784 That was the commit that added support for semihosting to softmmu in 2007, so I don't think suggesting that this is a 'fix' to that makes much sense. This has just been broken forever. (It's also pretty unimportant as a bug because the semihosting 'errno' is so ill-defined as to be unused, I think.) thanks -- PMM
On 9/16/19 7:15 AM, Peter Maydell wrote: > The set_swi_errno() function is called to capture the errno > from a host system call, so that we can return -1 from the > semihosting function and later allow the guest to get a more > specific error code with the SYS_ERRNO function. It comes in > two versions, one for user-only and one for softmmu. We forgot > to capture the errno in the softmmu version; fix the error. > > (Semihosting calls directed to gdb are unaffected because > they go through a different code path that captures the > error return from the gdbstub call in arm_semi_cb() or > arm_semi_flen_cb().) > > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > NB that a later commit will put in some cleanup of TaskState > that will let us reduce the duplication between the two > implementations of this function. > --- Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c index 90423a35deb..03e60105c05 100644 --- a/target/arm/arm-semi.c +++ b/target/arm/arm-semi.c @@ -114,8 +114,13 @@ static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code) return code; } #else +static target_ulong syscall_err; + static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code) { + if (code == (uint32_t)-1) { + syscall_err = errno; + } return code; } @@ -124,10 +129,6 @@ static inline uint32_t set_swi_errno(CPUARMState *env, uint32_t code) static target_ulong arm_semi_syscall_len; -#if !defined(CONFIG_USER_ONLY) -static target_ulong syscall_err; -#endif - static void arm_semi_cb(CPUState *cs, target_ulong ret, target_ulong err) { ARMCPU *cpu = ARM_CPU(cs);
The set_swi_errno() function is called to capture the errno from a host system call, so that we can return -1 from the semihosting function and later allow the guest to get a more specific error code with the SYS_ERRNO function. It comes in two versions, one for user-only and one for softmmu. We forgot to capture the errno in the softmmu version; fix the error. (Semihosting calls directed to gdb are unaffected because they go through a different code path that captures the error return from the gdbstub call in arm_semi_cb() or arm_semi_flen_cb().) Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- NB that a later commit will put in some cleanup of TaskState that will let us reduce the duplication between the two implementations of this function. --- target/arm/arm-semi.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)