Hi David, Firstly, thank you for you review. And then for your review, I worry that a memory leak will occur if QEMU exits after saves vmsd. So, we free it in post_save func.
Jinhao Gao -----Original Message----- From: David Gibson [mailto:da...@gibson.dropbear.id.au] Sent: 2020-12-28 14:58 To: gaojinhao <gaojin...@huawei.com> Cc: qemu-devel@nongnu.org; qemu-...@nongnu.org; Marc-André Lureau <marcandre.lur...@redhat.com>; Stefan Berger <stef...@linux.vnet.ibm.com>; Michael S . Tsirkin <m...@redhat.com>; Jason Wang <jasow...@redhat.com>; Greg Kurz <gr...@kaod.org>; Juan Quintela <quint...@redhat.com>; Dr . David Alan Gilbert <dgilb...@redhat.com>; Wanghaibin (D) <wanghaibin.w...@huawei.com>; zhukeqian <zhukeqi...@huawei.com> Subject: Re: [PATCH 4/8] spapr_pci: Fix memory leak of vmstate_spapr_pci On Sat, Dec 26, 2020 at 06:33:43PM +0800, g00517791 wrote: > From: Jinhao Gao <gaojin...@huawei.com> > > When VM migrate VMState of spapr_pci, the field(msi_devs) of spapr_pci > having a flag of VMS_ALLOC need to allocate memory. If the src doesn't > free memory of msi_devs in SaveStateEntry of spapr_pci after QEMUFile > save VMState of spapr_pci, it may result in memory leak of msi_devs. > We add the post_save func to free memory, which prevents memory leak. > > Signed-off-by: Jinhao Gao <gaojin...@huawei.com> Not really a memory leak, since it will get freed on the next pre_save. But, we might as well free it earlier if we can ,so Acked-by: David Gibson <da...@gibson.dropbear.id.au> > --- > hw/ppc/spapr_pci.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c index > 76d7c91e9c..1b2b940606 100644 > --- a/hw/ppc/spapr_pci.c > +++ b/hw/ppc/spapr_pci.c > @@ -2173,6 +2173,16 @@ static int spapr_pci_pre_save(void *opaque) > return 0; > } > > +static int spapr_pci_post_save(void *opaque) { > + SpaprPhbState *sphb = opaque; > + > + g_free(sphb->msi_devs); > + sphb->msi_devs = NULL; > + sphb->msi_devs_num = 0; > + return 0; > +} > + > static int spapr_pci_post_load(void *opaque, int version_id) { > SpaprPhbState *sphb = opaque; > @@ -2205,6 +2215,7 @@ static const VMStateDescription vmstate_spapr_pci = { > .version_id = 2, > .minimum_version_id = 2, > .pre_save = spapr_pci_pre_save, > + .post_save = spapr_pci_post_save, > .post_load = spapr_pci_post_load, > .fields = (VMStateField[]) { > VMSTATE_UINT64_EQUAL(buid, SpaprPhbState, NULL), -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson