Re: [libvirt RFC] qemu_saveimage: only use wrapper when using --bypass-cache

On Tue, Apr 12, 2022 at 2:48 PM Claudio Fontana <cfontana(a)suse.de&gt; wrote: > > align the "save" with the "restore" code, > by only using the wrapper when using --bypass-cache. > > This avoids a copy, resulting in better performance. > > Signed-off-by: Claudio Fontana <cfontana(a)suse.de&gt; > --- > src/qemu/qemu_saveimage.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c > index 4fd4c5cfcd..5ea1b2fbcc 100644 > --- a/src/qemu/qemu_saveimage.c > +++ b/src/qemu/qemu_saveimage.c > @@ -289,8 +289,10 @@ qemuSaveImageCreate(virQEMUDriver *driver, > if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, fd) < 0) > goto cleanup; > > - if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags))) > - goto cleanup; > + if ((flags & VIR_DOMAIN_SAVE_BYPASS_CACHE)) { > + if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags))) > + goto cleanup; > + } There is an obvious issue with this code. We are trying to close and free a file descriptor that we have not opened when VIR_DOMAIN_SAVE_BYPASS_CACHE is set in flags.

> > if (virQEMUSaveDataWrite(data, fd, path) < 0) > goto cleanup; > -- > 2.34.1 >