| Message ID | 1320261806-13194-4-git-send-email-agraf@suse.de |
|---|---|
| State | New |
| Headers | show |
Alexander Graf wrote: > glibc's pthread_attr_getstack tries to find the stack range from > /proc/self/maps. Unfortunately, /proc is usually the host's /proc > which means linux-user guests see qemu's stack there. > > Fake the file with a constructed maps entry that exposes the guest's > stack range. > > Signed-off-by: Alexander Graf <agraf@suse.de> > --- > linux-user/syscall.c | 15 +++++++++++++++ > 1 files changed, 15 insertions(+), 0 deletions(-) > > diff --git a/linux-user/syscall.c b/linux-user/syscall.c > index 38953ba..a51b457 100644 > --- a/linux-user/syscall.c > +++ b/linux-user/syscall.c > @@ -4600,6 +4600,20 @@ int get_osversion(void) > return osversion; > } > > + > +static int open_self_maps(void *cpu_env, int fd) > +{ > + TaskState *ts = ((CPUState *)cpu_env)->opaque; > + > + dprintf(fd, "%08llx-%08llx rw-p %08llx 00:00 0 [stack]\n", > + (unsigned long long)ts->info->stack_limit, > + (unsigned long long)(ts->stack_base + (TARGET_PAGE_SIZE - 1)) > + & TARGET_PAGE_MASK, > This needs to be guarded by: #if defined(TARGET_ARM) || defined(TARGET_M68K) || defined(TARGET_UNICORE32) Any idea how to fetch the stack range from somewhere else for other archs? Alex
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 38953ba..a51b457 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -4600,6 +4600,20 @@ int get_osversion(void) return osversion; } + +static int open_self_maps(void *cpu_env, int fd) +{ + TaskState *ts = ((CPUState *)cpu_env)->opaque; + + dprintf(fd, "%08llx-%08llx rw-p %08llx 00:00 0 [stack]\n", + (unsigned long long)ts->info->stack_limit, + (unsigned long long)(ts->stack_base + (TARGET_PAGE_SIZE - 1)) + & TARGET_PAGE_MASK, + (unsigned long long)ts->stack_base); + + return 0; +} + static int do_open(void *cpu_env, const char *pathname, int flags, mode_t mode) { struct fake_open { @@ -4608,6 +4622,7 @@ static int do_open(void *cpu_env, const char *pathname, int flags, mode_t mode) }; const struct fake_open *fake_open; static const struct fake_open fakes[] = { + { "/proc/self/maps", open_self_maps }, { NULL, NULL } };
glibc's pthread_attr_getstack tries to find the stack range from /proc/self/maps. Unfortunately, /proc is usually the host's /proc which means linux-user guests see qemu's stack there. Fake the file with a constructed maps entry that exposes the guest's stack range. Signed-off-by: Alexander Graf <agraf@suse.de> --- linux-user/syscall.c | 15 +++++++++++++++ 1 files changed, 15 insertions(+), 0 deletions(-)