On Fri, Dec 08, 2017 at 09:09:06AM -0500, Marcel Apfelbaum wrote: > > > ----- Original Message ----- > > From: "Ladi Prosek" <lpro...@redhat.com> > > To: qemu-devel@nongnu.org > > Cc: mar...@redhat.com, ge...@hostfission.com, m...@redhat.com, "alex > > williamson" <alex.william...@redhat.com> > > Sent: Friday, December 8, 2017 8:31:13 AM > > Subject: [PATCH v2] msix: don't mask already masked vectors on reset > > > > msix_mask_all() is supposed to invoke the release vector notifier if the > > state of the > > respective vector changed from unmasked to masked. The way it's currently > > called from > > msix_reset(), though, may result in calling the release notifier even if the > > vector > > is already masked. > > > > 1) msix_reset() clears out the msix_cap field and the msix_table. > > 2) msix_mask_all() runs with was_masked=false for all vectors because of 1), > > which > > results in calling the release notifier on all vectors. > > 3) if msix_reset() is subsequently called again, it goes through the same > > steps and > > calls the release notifier on all vectors again. > > > > This commit moves msix_mask_all() up so it runs before the device state is > > lost. And > > it adds an assignment to msix_function_masked so that the device remembers > > that > > MSI-X is masked. > > > > This is likely a low impact issue, found while debugging an already broken > > device. It > > is however easy to fix and the expectation that the use and release notifier > > invocations > > are always balanced is very natural. > > > > Signed-off-by: Ladi Prosek <lpro...@redhat.com> > > --- > > > > v1->v2: > > * fixed typo in commit message "or" -> "to" (Marcel) > > * directly set msix_function_masked to true instead of calling > > msix_update_function_masked() (Marcel) > > > > > > hw/pci/msix.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/hw/pci/msix.c b/hw/pci/msix.c > > index c944c02135..d6a4dbdb6b 100644 > > --- a/hw/pci/msix.c > > +++ b/hw/pci/msix.c > > @@ -500,11 +500,12 @@ void msix_reset(PCIDevice *dev) > > return; > > } > > msix_clear_all_vectors(dev); > > + msix_mask_all(dev, dev->msix_entries_nr); > > dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] &= > > ~dev->wmask[dev->msix_cap + MSIX_CONTROL_OFFSET]; > > memset(dev->msix_table, 0, dev->msix_entries_nr * PCI_MSIX_ENTRY_SIZE); > > memset(dev->msix_pba, 0, QEMU_ALIGN_UP(dev->msix_entries_nr, 64) / 8); > > - msix_mask_all(dev, dev->msix_entries_nr); > > + dev->msix_function_masked = true; > > } > > > > /* PCI spec suggests that devices make it possible for software to > > configure > > -- > > 2.13.6 > > > > > > Thanks Ladi! > > Reviewed-by: Marcel Apfelbaum <mar...@redhat.com>
This breaks make check though. Marcel - could you take a look please? -- MST
