| Message ID | 20171208074515.1553-5-lprosek@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Ladi Prosek <lprosek@redhat.com> writes: > The effects of ivshmem_enable_irqfd() was not undone on device reset. > > This manifested as: > ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. > > when irqfd was enabled before reset and then enabled again after reset, making > ivshmem_enable_irqfd() run for the second time. > > To reproduce, run: > > ivshmem-server > > and QEMU with: > > -device ivshmem-doorbell,chardev=iv > -chardev socket,path=/tmp/ivshmem_socket,id=iv > > then install the Windows driver, at the time of writing available at: > > https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem > > and crash-reboot the guest by inducing a BSOD. > > Signed-off-by: Ladi Prosek <lprosek@redhat.com> > --- > hw/misc/ivshmem.c | 24 +++++++++++++----------- > 1 file changed, 13 insertions(+), 11 deletions(-) > > diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c > index d1bb246d12..4be0d2627b 100644 > --- a/hw/misc/ivshmem.c > +++ b/hw/misc/ivshmem.c > @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) > } > } > > -static void ivshmem_reset(DeviceState *d) > -{ > - IVShmemState *s = IVSHMEM_COMMON(d); > - > - s->intrstatus = 0; > - s->intrmask = 0; > - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { > - ivshmem_msix_vector_use(s); > - } > -} > - > static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) > { > /* allocate QEMU callback data for receiving interrupts */ > @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) > > } > > +static void ivshmem_reset(DeviceState *d) > +{ > + IVShmemState *s = IVSHMEM_COMMON(d); > + > + ivshmem_disable_irqfd(s); > + > + s->intrstatus = 0; > + s->intrmask = 0; > + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { > + ivshmem_msix_vector_use(s); > + } > +} > + > static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, > uint32_t val, int len) > { Why are you moving ivshmem_reset()? Makes the actual change harder to see than necessary.
On Fri, Dec 8, 2017 at 2:36 PM, Markus Armbruster <armbru@redhat.com> wrote: > Ladi Prosek <lprosek@redhat.com> writes: > >> The effects of ivshmem_enable_irqfd() was not undone on device reset. >> >> This manifested as: >> ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. >> >> when irqfd was enabled before reset and then enabled again after reset, making >> ivshmem_enable_irqfd() run for the second time. >> >> To reproduce, run: >> >> ivshmem-server >> >> and QEMU with: >> >> -device ivshmem-doorbell,chardev=iv >> -chardev socket,path=/tmp/ivshmem_socket,id=iv >> >> then install the Windows driver, at the time of writing available at: >> >> https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem >> >> and crash-reboot the guest by inducing a BSOD. >> >> Signed-off-by: Ladi Prosek <lprosek@redhat.com> >> --- >> hw/misc/ivshmem.c | 24 +++++++++++++----------- >> 1 file changed, 13 insertions(+), 11 deletions(-) >> >> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >> index d1bb246d12..4be0d2627b 100644 >> --- a/hw/misc/ivshmem.c >> +++ b/hw/misc/ivshmem.c >> @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) >> } >> } >> >> -static void ivshmem_reset(DeviceState *d) >> -{ >> - IVShmemState *s = IVSHMEM_COMMON(d); >> - >> - s->intrstatus = 0; >> - s->intrmask = 0; >> - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >> - ivshmem_msix_vector_use(s); >> - } >> -} >> - >> static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) >> { >> /* allocate QEMU callback data for receiving interrupts */ >> @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) >> >> } >> >> +static void ivshmem_reset(DeviceState *d) >> +{ >> + IVShmemState *s = IVSHMEM_COMMON(d); >> + >> + ivshmem_disable_irqfd(s); >> + >> + s->intrstatus = 0; >> + s->intrmask = 0; >> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >> + ivshmem_msix_vector_use(s); >> + } >> +} >> + >> static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, >> uint32_t val, int len) >> { > > Why are you moving ivshmem_reset()? Makes the actual change harder to > see than necessary. ivshmem_disable_irqfd() is declared after ivshmem_reset() in the source file. I generally prefer to order static functions topologically if possible. If you'd prefer adding a forward decl instead (fewer lines touched, easier to bisect?) I can certainly do that. Thanks!
On 12/08/2017 07:44 AM, Ladi Prosek wrote: >>> static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, >>> uint32_t val, int len) >>> { >> >> Why are you moving ivshmem_reset()? Makes the actual change harder to >> see than necessary. > > ivshmem_disable_irqfd() is declared after ivshmem_reset() in the > source file. I generally prefer to order static functions > topologically if possible. If you'd prefer adding a forward decl > instead (fewer lines touched, easier to bisect?) I can certainly do > that. Thanks! That, or split it into two patches (one doing just the code motion, the other making the semantic change).
Ladi Prosek <lprosek@redhat.com> writes: > On Fri, Dec 8, 2017 at 2:36 PM, Markus Armbruster <armbru@redhat.com> wrote: >> Ladi Prosek <lprosek@redhat.com> writes: >> >>> The effects of ivshmem_enable_irqfd() was not undone on device reset. >>> >>> This manifested as: >>> ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. >>> >>> when irqfd was enabled before reset and then enabled again after reset, making >>> ivshmem_enable_irqfd() run for the second time. >>> >>> To reproduce, run: >>> >>> ivshmem-server >>> >>> and QEMU with: >>> >>> -device ivshmem-doorbell,chardev=iv >>> -chardev socket,path=/tmp/ivshmem_socket,id=iv >>> >>> then install the Windows driver, at the time of writing available at: >>> >>> https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem >>> >>> and crash-reboot the guest by inducing a BSOD. >>> >>> Signed-off-by: Ladi Prosek <lprosek@redhat.com> >>> --- >>> hw/misc/ivshmem.c | 24 +++++++++++++----------- >>> 1 file changed, 13 insertions(+), 11 deletions(-) >>> >>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >>> index d1bb246d12..4be0d2627b 100644 >>> --- a/hw/misc/ivshmem.c >>> +++ b/hw/misc/ivshmem.c >>> @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) >>> } >>> } >>> >>> -static void ivshmem_reset(DeviceState *d) >>> -{ >>> - IVShmemState *s = IVSHMEM_COMMON(d); >>> - >>> - s->intrstatus = 0; >>> - s->intrmask = 0; >>> - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>> - ivshmem_msix_vector_use(s); >>> - } >>> -} >>> - >>> static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) >>> { >>> /* allocate QEMU callback data for receiving interrupts */ >>> @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) >>> >>> } >>> >>> +static void ivshmem_reset(DeviceState *d) >>> +{ >>> + IVShmemState *s = IVSHMEM_COMMON(d); >>> + >>> + ivshmem_disable_irqfd(s); >>> + >>> + s->intrstatus = 0; >>> + s->intrmask = 0; >>> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>> + ivshmem_msix_vector_use(s); >>> + } >>> +} >>> + >>> static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, >>> uint32_t val, int len) >>> { >> >> Why are you moving ivshmem_reset()? Makes the actual change harder to >> see than necessary. > > ivshmem_disable_irqfd() is declared after ivshmem_reset() in the > source file. I generally prefer to order static functions > topologically if possible. If you'd prefer adding a forward decl > instead (fewer lines touched, easier to bisect?) I can certainly do > that. Thanks! Well, it compiles before your patch, your patch doesn't add any calls, so I can't quite see why a forward declaration would be needed.
On Fri, Dec 8, 2017 at 6:28 PM, Markus Armbruster <armbru@redhat.com> wrote: > Ladi Prosek <lprosek@redhat.com> writes: > >> On Fri, Dec 8, 2017 at 2:36 PM, Markus Armbruster <armbru@redhat.com> wrote: >>> Ladi Prosek <lprosek@redhat.com> writes: >>> >>>> The effects of ivshmem_enable_irqfd() was not undone on device reset. >>>> >>>> This manifested as: >>>> ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. >>>> >>>> when irqfd was enabled before reset and then enabled again after reset, making >>>> ivshmem_enable_irqfd() run for the second time. >>>> >>>> To reproduce, run: >>>> >>>> ivshmem-server >>>> >>>> and QEMU with: >>>> >>>> -device ivshmem-doorbell,chardev=iv >>>> -chardev socket,path=/tmp/ivshmem_socket,id=iv >>>> >>>> then install the Windows driver, at the time of writing available at: >>>> >>>> https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem >>>> >>>> and crash-reboot the guest by inducing a BSOD. >>>> >>>> Signed-off-by: Ladi Prosek <lprosek@redhat.com> >>>> --- >>>> hw/misc/ivshmem.c | 24 +++++++++++++----------- >>>> 1 file changed, 13 insertions(+), 11 deletions(-) >>>> >>>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >>>> index d1bb246d12..4be0d2627b 100644 >>>> --- a/hw/misc/ivshmem.c >>>> +++ b/hw/misc/ivshmem.c >>>> @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) >>>> } >>>> } >>>> >>>> -static void ivshmem_reset(DeviceState *d) >>>> -{ >>>> - IVShmemState *s = IVSHMEM_COMMON(d); >>>> - >>>> - s->intrstatus = 0; >>>> - s->intrmask = 0; >>>> - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>>> - ivshmem_msix_vector_use(s); >>>> - } >>>> -} >>>> - >>>> static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) >>>> { >>>> /* allocate QEMU callback data for receiving interrupts */ >>>> @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) >>>> >>>> } >>>> >>>> +static void ivshmem_reset(DeviceState *d) >>>> +{ >>>> + IVShmemState *s = IVSHMEM_COMMON(d); >>>> + >>>> + ivshmem_disable_irqfd(s); >>>> + >>>> + s->intrstatus = 0; >>>> + s->intrmask = 0; >>>> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>>> + ivshmem_msix_vector_use(s); >>>> + } >>>> +} >>>> + >>>> static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, >>>> uint32_t val, int len) >>>> { >>> >>> Why are you moving ivshmem_reset()? Makes the actual change harder to >>> see than necessary. >> >> ivshmem_disable_irqfd() is declared after ivshmem_reset() in the >> source file. I generally prefer to order static functions >> topologically if possible. If you'd prefer adding a forward decl >> instead (fewer lines touched, easier to bisect?) I can certainly do >> that. Thanks! > > Well, it compiles before your patch, your patch doesn't add any calls, > so I can't quite see why a forward declaration would be needed. It adds a call to ivshmem_disable_irqfd().
Ladi Prosek <lprosek@redhat.com> writes: > On Fri, Dec 8, 2017 at 6:28 PM, Markus Armbruster <armbru@redhat.com> wrote: >> Ladi Prosek <lprosek@redhat.com> writes: >> >>> On Fri, Dec 8, 2017 at 2:36 PM, Markus Armbruster <armbru@redhat.com> wrote: >>>> Ladi Prosek <lprosek@redhat.com> writes: >>>> >>>>> The effects of ivshmem_enable_irqfd() was not undone on device reset. >>>>> >>>>> This manifested as: >>>>> ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. >>>>> >>>>> when irqfd was enabled before reset and then enabled again after reset, making >>>>> ivshmem_enable_irqfd() run for the second time. >>>>> >>>>> To reproduce, run: >>>>> >>>>> ivshmem-server >>>>> >>>>> and QEMU with: >>>>> >>>>> -device ivshmem-doorbell,chardev=iv >>>>> -chardev socket,path=/tmp/ivshmem_socket,id=iv >>>>> >>>>> then install the Windows driver, at the time of writing available at: >>>>> >>>>> https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem >>>>> >>>>> and crash-reboot the guest by inducing a BSOD. >>>>> >>>>> Signed-off-by: Ladi Prosek <lprosek@redhat.com> >>>>> --- >>>>> hw/misc/ivshmem.c | 24 +++++++++++++----------- >>>>> 1 file changed, 13 insertions(+), 11 deletions(-) >>>>> >>>>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c >>>>> index d1bb246d12..4be0d2627b 100644 >>>>> --- a/hw/misc/ivshmem.c >>>>> +++ b/hw/misc/ivshmem.c >>>>> @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) >>>>> } >>>>> } >>>>> >>>>> -static void ivshmem_reset(DeviceState *d) >>>>> -{ >>>>> - IVShmemState *s = IVSHMEM_COMMON(d); >>>>> - >>>>> - s->intrstatus = 0; >>>>> - s->intrmask = 0; >>>>> - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>>>> - ivshmem_msix_vector_use(s); >>>>> - } >>>>> -} >>>>> - >>>>> static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) >>>>> { >>>>> /* allocate QEMU callback data for receiving interrupts */ >>>>> @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) >>>>> >>>>> } >>>>> >>>>> +static void ivshmem_reset(DeviceState *d) >>>>> +{ >>>>> + IVShmemState *s = IVSHMEM_COMMON(d); >>>>> + >>>>> + ivshmem_disable_irqfd(s); >>>>> + >>>>> + s->intrstatus = 0; >>>>> + s->intrmask = 0; >>>>> + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { >>>>> + ivshmem_msix_vector_use(s); >>>>> + } >>>>> +} >>>>> + >>>>> static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, >>>>> uint32_t val, int len) >>>>> { >>>> >>>> Why are you moving ivshmem_reset()? Makes the actual change harder to >>>> see than necessary. >>> >>> ivshmem_disable_irqfd() is declared after ivshmem_reset() in the >>> source file. I generally prefer to order static functions >>> topologically if possible. If you'd prefer adding a forward decl >>> instead (fewer lines touched, easier to bisect?) I can certainly do >>> that. Thanks! >> >> Well, it compiles before your patch, your patch doesn't add any calls, >> so I can't quite see why a forward declaration would be needed. > > It adds a call to ivshmem_disable_irqfd(). Note to self: patch review on Friday late afternoon is a bad idea. I'd prefer the forward declaration. Thanks!
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index d1bb246d12..4be0d2627b 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -758,17 +758,6 @@ static void ivshmem_msix_vector_use(IVShmemState *s) } } -static void ivshmem_reset(DeviceState *d) -{ - IVShmemState *s = IVSHMEM_COMMON(d); - - s->intrstatus = 0; - s->intrmask = 0; - if (ivshmem_has_feature(s, IVSHMEM_MSI)) { - ivshmem_msix_vector_use(s); - } -} - static int ivshmem_setup_interrupts(IVShmemState *s, Error **errp) { /* allocate QEMU callback data for receiving interrupts */ @@ -855,6 +844,19 @@ static void ivshmem_disable_irqfd(IVShmemState *s) } +static void ivshmem_reset(DeviceState *d) +{ + IVShmemState *s = IVSHMEM_COMMON(d); + + ivshmem_disable_irqfd(s); + + s->intrstatus = 0; + s->intrmask = 0; + if (ivshmem_has_feature(s, IVSHMEM_MSI)) { + ivshmem_msix_vector_use(s); + } +} + static void ivshmem_write_config(PCIDevice *pdev, uint32_t address, uint32_t val, int len) {
The effects of ivshmem_enable_irqfd() was not undone on device reset. This manifested as: ivshmem_add_kvm_msi_virq: Assertion `!s->msi_vectors[vector].pdev' failed. when irqfd was enabled before reset and then enabled again after reset, making ivshmem_enable_irqfd() run for the second time. To reproduce, run: ivshmem-server and QEMU with: -device ivshmem-doorbell,chardev=iv -chardev socket,path=/tmp/ivshmem_socket,id=iv then install the Windows driver, at the time of writing available at: https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/ivshmem and crash-reboot the guest by inducing a BSOD. Signed-off-by: Ladi Prosek <lprosek@redhat.com> --- hw/misc/ivshmem.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-)