> "As I mentioned earlier": where? > Otherwise this description will be of > little relevance in 5 years from now in our history.
I explained the motivation on the first revision of the patch On Wed, May 7, 2025, 14:58 Philippe Mathieu-Daudé <phi...@linaro.org> wrote: > Hi Elisha, > > On 6/5/25 18:44, Elisha Hollander wrote: > > > As I mentioned earlier, let's say you don't initialize the vertical > > "As I mentioned earlier": where? Otherwise this description will be of > little relevance in 5 years from now in our history. > > > display end registers, and set the minimum scanline register, the > > emulation will then have to allocate some display buffer, but because > > the vertical display end is initilized as 0 the buffer will be empty and > > Typo "initialized". > > > the program break. > > > > Signed-off-by: donno2048 <just4now666...@gmail.com > > <mailto:just4now666...@gmail.com>> > > > > --- > > util/memfd.c | 10 ++++++---- > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > diff --git a/util/memfd.c b/util/memfd.c > > index 8a2e906..e96e5af 100644 > > --- a/util/memfd.c > > +++ b/util/memfd.c > > @@ -108,7 +108,7 @@ err: > > void *qemu_memfd_alloc(const char *name, size_t size, unsigned int > seals, > > int *fd, Error **errp) > > { > > - void *ptr; > > + void *ptr = NULL; > > int mfd = qemu_memfd_create(name, size, false, 0, seals, NULL); > > > > /* some systems have memfd without sealing */ > > @@ -131,9 +131,11 @@ void *qemu_memfd_alloc(const char *name, size_t > > size, unsigned int seals, > > } > > } > > > > - ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > > - if (ptr == MAP_FAILED) { > > - goto err; > > + if (size != 0) { > > + ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > > + if (ptr == MAP_FAILED) { > > + goto err; > > + } > > } > > > > *fd = mfd; > > -- > > 2.30.2 > > Alternatively always set *fd, removing the @err label: > > -- >8 -- > @@ -132,0 +133 @@ void *qemu_memfd_alloc(const char *name, size_t size, > unsigned int seals, > + *fd = mfd; > @@ -134,3 +135,2 @@ void *qemu_memfd_alloc(const char *name, size_t > size, unsigned int seals, > - ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > - if (ptr == MAP_FAILED) { > - goto err; > + if (!size) { > + return NULL; > @@ -139,2 +139,4 @@ void *qemu_memfd_alloc(const char *name, size_t > size, unsigned int seals, > - *fd = mfd; > - return ptr; > + ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > + if (ptr != MAP_FAILED) { > + return ptr; > + } > @@ -142 +143,0 @@ void *qemu_memfd_alloc(const char *name, size_t size, > unsigned int seals, > -err: > --- > > Or more similar to your approach: > > -- >8 -- > @@ -111 +111 @@ void *qemu_memfd_alloc(const char *name, size_t size, > unsigned int seals, > - void *ptr; > + void *ptr = NULL; > @@ -134,5 +133,0 @@ void *qemu_memfd_alloc(const char *name, size_t > size, unsigned int seals, > - ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > - if (ptr == MAP_FAILED) { > - goto err; > - } > - > @@ -140 +134,0 @@ void *qemu_memfd_alloc(const char *name, size_t size, > unsigned int seals, > - return ptr; > @@ -142,4 +136,2 @@ void *qemu_memfd_alloc(const char *name, size_t > size, unsigned int seals, > -err: > - error_setg_errno(errp, errno, "failed to allocate shared memory"); > - if (mfd >= 0) { > - close(mfd); > + if (!size) { > + return NULL; > @@ -147 +139,11 @@ err: > - return NULL; > + > + if (size) { > + ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0); > + if (ptr == MAP_FAILED) { > + error_setg_errno(errp, errno, "failed to allocate shared > memory"); > + if (mfd >= 0) { > + close(mfd); > + } > + } > + } > + return ptr; > --- >
