| Message ID | 4d8a74a512bf55f39c5d1be115b1c52b6a632e09.1716912651.git.mprivozn@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | backends/hostmem: Round up memory size for qemu_madvise() and mbind() | expand |
Am 28.05.24 um 18:15 schrieb Michal Privoznik: > The unspoken premise of qemu_madvise() is that errno is set on > error. And it is mostly the case except for posix_madvise() which > is documented to return either zero (on success) or a positive > error number. This means, we must set errno ourselves. And while > at it, make the function return a negative value on error, just > like other error paths do. > > Signed-off-by: Michal Privoznik <mprivozn@redhat.com> > --- > util/osdep.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/util/osdep.c b/util/osdep.c > index e996c4744a..e42f4e8121 100644 > --- a/util/osdep.c > +++ b/util/osdep.c > @@ -57,7 +57,12 @@ int qemu_madvise(void *addr, size_t len, int advice) > #if defined(CONFIG_MADVISE) > return madvise(addr, len, advice); > #elif defined(CONFIG_POSIX_MADVISE) > - return posix_madvise(addr, len, advice); > + int rc = posix_madvise(addr, len, advice); > + if (rc) { > + errno = rc; > + return -1; > + } > + return 0; > #else > errno = EINVAL; > return -1; Interesting, seems to be correct Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/util/osdep.c b/util/osdep.c index e996c4744a..e42f4e8121 100644 --- a/util/osdep.c +++ b/util/osdep.c @@ -57,7 +57,12 @@ int qemu_madvise(void *addr, size_t len, int advice) #if defined(CONFIG_MADVISE) return madvise(addr, len, advice); #elif defined(CONFIG_POSIX_MADVISE) - return posix_madvise(addr, len, advice); + int rc = posix_madvise(addr, len, advice); + if (rc) { + errno = rc; + return -1; + } + return 0; #else errno = EINVAL; return -1;
The unspoken premise of qemu_madvise() is that errno is set on error. And it is mostly the case except for posix_madvise() which is documented to return either zero (on success) or a positive error number. This means, we must set errno ourselves. And while at it, make the function return a negative value on error, just like other error paths do. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- util/osdep.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)