| Message ID | 20201005061957.13509-1-jgross@suse.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | xen/events: don't use chip_data for legacy IRQs | expand |
Any reason this has not made it into 5.4.y and older by now? This patch is fixing a real problem... Juergen On 05.10.20 08:19, Juergen Gross wrote: > Since commit c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") > Xen is using the chip_data pointer for storing IRQ specific data. When > running as a HVM domain this can result in problems for legacy IRQs, as > those might use chip_data for their own purposes. > > Use a local array for this purpose in case of legacy IRQs, avoiding the > double use. > > Fixes: c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") > Signed-off-by: Juergen Gross <jgross@suse.com> > Tested-by: Stefan Bader <stefan.bader@canonical.com> > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> > Link: https://lore.kernel.org/r/20200930091614.13660-1-jgross@suse.com > --- > This is a backport for stable kernel 5.4.y and older > --- > drivers/xen/events/events_base.c | 29 +++++++++++++++++++++-------- > 1 file changed, 21 insertions(+), 8 deletions(-) > > diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c > index 55f2b834cf13..e402620b8920 100644 > --- a/drivers/xen/events/events_base.c > +++ b/drivers/xen/events/events_base.c > @@ -91,6 +91,8 @@ static bool (*pirq_needs_eoi)(unsigned irq); > /* Xen will never allocate port zero for any purpose. */ > #define VALID_EVTCHN(chn) ((chn) != 0) > > +static struct irq_info *legacy_info_ptrs[NR_IRQS_LEGACY]; > + > static struct irq_chip xen_dynamic_chip; > static struct irq_chip xen_percpu_chip; > static struct irq_chip xen_pirq_chip; > @@ -155,7 +157,18 @@ int get_evtchn_to_irq(unsigned evtchn) > /* Get info for IRQ */ > struct irq_info *info_for_irq(unsigned irq) > { > - return irq_get_chip_data(irq); > + if (irq < nr_legacy_irqs()) > + return legacy_info_ptrs[irq]; > + else > + return irq_get_chip_data(irq); > +} > + > +static void set_info_for_irq(unsigned int irq, struct irq_info *info) > +{ > + if (irq < nr_legacy_irqs()) > + legacy_info_ptrs[irq] = info; > + else > + irq_set_chip_data(irq, info); > } > > /* Constructors for packed IRQ information. */ > @@ -376,7 +389,7 @@ static void xen_irq_init(unsigned irq) > info->type = IRQT_UNBOUND; > info->refcnt = -1; > > - irq_set_chip_data(irq, info); > + set_info_for_irq(irq, info); > > list_add_tail(&info->list, &xen_irq_list_head); > } > @@ -425,14 +438,14 @@ static int __must_check xen_allocate_irq_gsi(unsigned gsi) > > static void xen_free_irq(unsigned irq) > { > - struct irq_info *info = irq_get_chip_data(irq); > + struct irq_info *info = info_for_irq(irq); > > if (WARN_ON(!info)) > return; > > list_del(&info->list); > > - irq_set_chip_data(irq, NULL); > + set_info_for_irq(irq, NULL); > > WARN_ON(info->refcnt > 0); > > @@ -602,7 +615,7 @@ EXPORT_SYMBOL_GPL(xen_irq_from_gsi); > static void __unbind_from_irq(unsigned int irq) > { > int evtchn = evtchn_from_irq(irq); > - struct irq_info *info = irq_get_chip_data(irq); > + struct irq_info *info = info_for_irq(irq); > > if (info->refcnt > 0) { > info->refcnt--; > @@ -1106,7 +1119,7 @@ int bind_ipi_to_irqhandler(enum ipi_vector ipi, > > void unbind_from_irqhandler(unsigned int irq, void *dev_id) > { > - struct irq_info *info = irq_get_chip_data(irq); > + struct irq_info *info = info_for_irq(irq); > > if (WARN_ON(!info)) > return; > @@ -1140,7 +1153,7 @@ int evtchn_make_refcounted(unsigned int evtchn) > if (irq == -1) > return -ENOENT; > > - info = irq_get_chip_data(irq); > + info = info_for_irq(irq); > > if (!info) > return -ENOENT; > @@ -1168,7 +1181,7 @@ int evtchn_get(unsigned int evtchn) > if (irq == -1) > goto done; > > - info = irq_get_chip_data(irq); > + info = info_for_irq(irq); > > if (!info) > goto done; >
On Wed, Oct 14, 2020 at 11:31:33AM +0200, Jürgen Groß wrote: > Any reason this has not made it into 5.4.y and older by now? > > This patch is fixing a real problem... What is the git commit id of this patch in Linus's tree? thanks, greg k-h
On 14.10.20 11:51, Greg KH wrote: > On Wed, Oct 14, 2020 at 11:31:33AM +0200, Jürgen Groß wrote: >> Any reason this has not made it into 5.4.y and older by now? >> >> This patch is fixing a real problem... > > What is the git commit id of this patch in Linus's tree? 0891fb39ba67bd7ae023ea0d367297ffff010781 Juergen
On Wed, Oct 14, 2020 at 12:44:39PM +0200, Jürgen Groß wrote: > On 14.10.20 11:51, Greg KH wrote: > > On Wed, Oct 14, 2020 at 11:31:33AM +0200, Jürgen Groß wrote: > > > Any reason this has not made it into 5.4.y and older by now? > > > > > > This patch is fixing a real problem... > > > > What is the git commit id of this patch in Linus's tree? > > 0891fb39ba67bd7ae023ea0d367297ffff010781 Thank you, now queued up. Always try to remember that next time, as it's required. thanks, greg k-h
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 55f2b834cf13..e402620b8920 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -91,6 +91,8 @@ static bool (*pirq_needs_eoi)(unsigned irq); /* Xen will never allocate port zero for any purpose. */ #define VALID_EVTCHN(chn) ((chn) != 0) +static struct irq_info *legacy_info_ptrs[NR_IRQS_LEGACY]; + static struct irq_chip xen_dynamic_chip; static struct irq_chip xen_percpu_chip; static struct irq_chip xen_pirq_chip; @@ -155,7 +157,18 @@ int get_evtchn_to_irq(unsigned evtchn) /* Get info for IRQ */ struct irq_info *info_for_irq(unsigned irq) { - return irq_get_chip_data(irq); + if (irq < nr_legacy_irqs()) + return legacy_info_ptrs[irq]; + else + return irq_get_chip_data(irq); +} + +static void set_info_for_irq(unsigned int irq, struct irq_info *info) +{ + if (irq < nr_legacy_irqs()) + legacy_info_ptrs[irq] = info; + else + irq_set_chip_data(irq, info); } /* Constructors for packed IRQ information. */ @@ -376,7 +389,7 @@ static void xen_irq_init(unsigned irq) info->type = IRQT_UNBOUND; info->refcnt = -1; - irq_set_chip_data(irq, info); + set_info_for_irq(irq, info); list_add_tail(&info->list, &xen_irq_list_head); } @@ -425,14 +438,14 @@ static int __must_check xen_allocate_irq_gsi(unsigned gsi) static void xen_free_irq(unsigned irq) { - struct irq_info *info = irq_get_chip_data(irq); + struct irq_info *info = info_for_irq(irq); if (WARN_ON(!info)) return; list_del(&info->list); - irq_set_chip_data(irq, NULL); + set_info_for_irq(irq, NULL); WARN_ON(info->refcnt > 0); @@ -602,7 +615,7 @@ EXPORT_SYMBOL_GPL(xen_irq_from_gsi); static void __unbind_from_irq(unsigned int irq) { int evtchn = evtchn_from_irq(irq); - struct irq_info *info = irq_get_chip_data(irq); + struct irq_info *info = info_for_irq(irq); if (info->refcnt > 0) { info->refcnt--; @@ -1106,7 +1119,7 @@ int bind_ipi_to_irqhandler(enum ipi_vector ipi, void unbind_from_irqhandler(unsigned int irq, void *dev_id) { - struct irq_info *info = irq_get_chip_data(irq); + struct irq_info *info = info_for_irq(irq); if (WARN_ON(!info)) return; @@ -1140,7 +1153,7 @@ int evtchn_make_refcounted(unsigned int evtchn) if (irq == -1) return -ENOENT; - info = irq_get_chip_data(irq); + info = info_for_irq(irq); if (!info) return -ENOENT; @@ -1168,7 +1181,7 @@ int evtchn_get(unsigned int evtchn) if (irq == -1) goto done; - info = irq_get_chip_data(irq); + info = info_for_irq(irq); if (!info) goto done;
Since commit c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") Xen is using the chip_data pointer for storing IRQ specific data. When running as a HVM domain this can result in problems for legacy IRQs, as those might use chip_data for their own purposes. Use a local array for this purpose in case of legacy IRQs, avoiding the double use. Fixes: c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Stefan Bader <stefan.bader@canonical.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20200930091614.13660-1-jgross@suse.com --- This is a backport for stable kernel 5.4.y and older --- drivers/xen/events/events_base.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)