| Message ID | 20190821142151.19995-2-sandra@codesourcery.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix bug in nios2 and m68k semihosting | expand |
On 8/21/19 4:21 PM, Sandra Loosemore wrote: > This patch fixes a bug that caused semihosted exit to always return > status 0; it was incorrectly using the value of register R_ARG0 (which > contains the HOSTED_EXIT request number) instead of register R_ARG1. > Fixes: 413a99a92c1 > Signed-off-by: Sandra Loosemore <sandra@codesourcery.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> > --- > target/nios2/nios2-semi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c > index d7a80dd..06c0861 100644 > --- a/target/nios2/nios2-semi.c > +++ b/target/nios2/nios2-semi.c > @@ -215,8 +215,8 @@ void do_nios2_semihosting(CPUNios2State *env) > args = env->regs[R_ARG1]; > switch (nr) { > case HOSTED_EXIT: > - gdb_exit(env, env->regs[R_ARG0]); > - exit(env->regs[R_ARG0]); > + gdb_exit(env, env->regs[R_ARG1]); > + exit(env->regs[R_ARG1]); > case HOSTED_OPEN: > GET_ARG(0); > GET_ARG(1); >
Le 21/08/2019 à 16:21, Sandra Loosemore a écrit : > This patch fixes a bug that caused semihosted exit to always return > status 0; it was incorrectly using the value of register R_ARG0 (which > contains the HOSTED_EXIT request number) instead of register R_ARG1. > > Signed-off-by: Sandra Loosemore <sandra@codesourcery.com> > --- > target/nios2/nios2-semi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c > index d7a80dd..06c0861 100644 > --- a/target/nios2/nios2-semi.c > +++ b/target/nios2/nios2-semi.c > @@ -215,8 +215,8 @@ void do_nios2_semihosting(CPUNios2State *env) > args = env->regs[R_ARG1]; > switch (nr) { > case HOSTED_EXIT: > - gdb_exit(env, env->regs[R_ARG0]); > - exit(env->regs[R_ARG0]); > + gdb_exit(env, env->regs[R_ARG1]); > + exit(env->regs[R_ARG1]); It's weird: in line 215, env->regs[R_ARG1] is args. Are you sure it's not something like: GET_ARG(0) gdb_exit(env, arg0); exit(arg0); same for m68k. Did you check the kernel code? Thanks, Laurent
On 8/21/19 8:41 AM, Laurent Vivier wrote: > Le 21/08/2019 à 16:21, Sandra Loosemore a écrit : >> This patch fixes a bug that caused semihosted exit to always return >> status 0; it was incorrectly using the value of register R_ARG0 (which >> contains the HOSTED_EXIT request number) instead of register R_ARG1. >> >> Signed-off-by: Sandra Loosemore <sandra@codesourcery.com> >> --- >> target/nios2/nios2-semi.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c >> index d7a80dd..06c0861 100644 >> --- a/target/nios2/nios2-semi.c >> +++ b/target/nios2/nios2-semi.c >> @@ -215,8 +215,8 @@ void do_nios2_semihosting(CPUNios2State *env) >> args = env->regs[R_ARG1]; >> switch (nr) { >> case HOSTED_EXIT: >> - gdb_exit(env, env->regs[R_ARG0]); >> - exit(env->regs[R_ARG0]); >> + gdb_exit(env, env->regs[R_ARG1]); >> + exit(env->regs[R_ARG1]); > > It's weird: in line 215, env->regs[R_ARG1] is args. > > Are you sure it's not something like: > > GET_ARG(0) > gdb_exit(env, arg0); > exit(arg0); > > same for m68k. > > Did you check the kernel code? It's not the kernel that's involved here, it's libgloss. And yes, the HOSTED_EXIT case takes an immediate argument in the register rather than a pointer to an argument block. Here's the documentation for nios2 semihosting. https://www.sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=libgloss/nios2/nios2-semi.txt;h=ded3a093c03dbae84cb95b4cd45bc3e0d751eda2;hb=HEAD And m68k: https://www.sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=libgloss/m68k/m68k-semi.txt;h=50520c15292aa7edf7eef28e09fd9202ce75b153;hb=HEAD Again, a lot of cutting and pasting involved here. ;-) -Sandra
Le 21/08/2019 à 17:27, Sandra Loosemore a écrit : > On 8/21/19 8:41 AM, Laurent Vivier wrote: >> Le 21/08/2019 à 16:21, Sandra Loosemore a écrit : >>> This patch fixes a bug that caused semihosted exit to always return >>> status 0; it was incorrectly using the value of register R_ARG0 (which >>> contains the HOSTED_EXIT request number) instead of register R_ARG1. >>> >>> Signed-off-by: Sandra Loosemore <sandra@codesourcery.com> >>> --- >>> target/nios2/nios2-semi.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c >>> index d7a80dd..06c0861 100644 >>> --- a/target/nios2/nios2-semi.c >>> +++ b/target/nios2/nios2-semi.c >>> @@ -215,8 +215,8 @@ void do_nios2_semihosting(CPUNios2State *env) >>> args = env->regs[R_ARG1]; >>> switch (nr) { >>> case HOSTED_EXIT: >>> - gdb_exit(env, env->regs[R_ARG0]); >>> - exit(env->regs[R_ARG0]); >>> + gdb_exit(env, env->regs[R_ARG1]); >>> + exit(env->regs[R_ARG1]); >> >> It's weird: in line 215, env->regs[R_ARG1] is args. >> >> Are you sure it's not something like: >> >> GET_ARG(0) >> gdb_exit(env, arg0); >> exit(arg0); >> >> same for m68k. >> >> Did you check the kernel code? > > It's not the kernel that's involved here, it's libgloss. And yes, the > HOSTED_EXIT case takes an immediate argument in the register rather than > a pointer to an argument block. > > Here's the documentation for nios2 semihosting. > > https://www.sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=libgloss/nios2/nios2-semi.txt;h=ded3a093c03dbae84cb95b4cd45bc3e0d751eda2;hb=HEAD > > > And m68k: > > https://www.sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;a=blob;f=libgloss/m68k/m68k-semi.txt;h=50520c15292aa7edf7eef28e09fd9202ce75b153;hb=HEAD > > > Again, a lot of cutting and pasting involved here. ;-) > > -Sandra Thank you for the details. Could add this information in the commit messages of each patch? Reviewed-by: Laurent Vivier <laurent@vivier.eu>
On 8/21/19 9:41 AM, Laurent Vivier wrote:
> Could add this information in the commit messages of each patch?
Sure. V2 of the patches coming up shortly.
-Sandra
diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c index d7a80dd..06c0861 100644 --- a/target/nios2/nios2-semi.c +++ b/target/nios2/nios2-semi.c @@ -215,8 +215,8 @@ void do_nios2_semihosting(CPUNios2State *env) args = env->regs[R_ARG1]; switch (nr) { case HOSTED_EXIT: - gdb_exit(env, env->regs[R_ARG0]); - exit(env->regs[R_ARG0]); + gdb_exit(env, env->regs[R_ARG1]); + exit(env->regs[R_ARG1]); case HOSTED_OPEN: GET_ARG(0); GET_ARG(1);
This patch fixes a bug that caused semihosted exit to always return status 0; it was incorrectly using the value of register R_ARG0 (which contains the HOSTED_EXIT request number) instead of register R_ARG1. Signed-off-by: Sandra Loosemore <sandra@codesourcery.com> --- target/nios2/nios2-semi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)