| Message ID | 20130508171519.26724.63307.stgit@grignak.americas.hpqcorp.net (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Wed, May 08, 2013 at 11:15:19AM -0600, Lance Ortiz wrote: > The following warning was seen on 3.9 when a corrected PCIe error was being > handled by the AER subsystem. > > WARNING: at .../drivers/pci/search.c:214 pci_get_dev_by_id+0x8a/0x90() > > This occurred because code was added to the function cper_print_pcie() that > calls the pci_get_domain_bus_and_slot() function. cper_print_pcie() is called > in an interrupt context and pci_get* functions are not supposed to be called > in that context hence the warning. > > The solution is to move the call to cper_print_aer() out of the interrupt > context and into aer_recover_queue() to avoid any warnings when calling > pci_get* functions. > > Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Looks good. Acked-by: Borislav Petkov <bp@suse.de>
On Wednesday, May 08, 2013 11:15:19 AM Lance Ortiz wrote: > The following warning was seen on 3.9 when a corrected PCIe error was being > handled by the AER subsystem. > > WARNING: at .../drivers/pci/search.c:214 pci_get_dev_by_id+0x8a/0x90() > > This occurred because code was added to the function cper_print_pcie() that > calls the pci_get_domain_bus_and_slot() function. Do you know which commit added that code? > cper_print_pcie() is called > in an interrupt context and pci_get* functions are not supposed to be called > in that context hence the warning. > > The solution is to move the call to cper_print_aer() out of the interrupt > context and into aer_recover_queue() to avoid any warnings when calling > pci_get* functions. The way the changes are described here isn't particularly clear to me. I'd say something like If cper_print_aer() is called by aer_recover_work_func(), there won't be any reason to call it from cper_print_pcie() any more, in which case all of the problematic code needed only to prepare for the cper_print_aer() call, including the invocation of pci_get_domain_bus_and_slot() causing the warning to be printed, may be removed from there. Make that happen." Also, since aer_recover_work_func() is going to be the only existing caller of cper_print_aer() after this change, as far as I can say, and it doesn't use the function's first argument, that argument should be dropped entirely. Thanks, Rafael > Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> > --- > > drivers/acpi/apei/cper.c | 18 ------------------ > drivers/acpi/apei/ghes.c | 3 ++- > drivers/pci/pcie/aer/aerdrv_core.c | 6 +++++- > include/linux/aer.h | 2 +- > 4 files changed, 8 insertions(+), 21 deletions(-) > > diff --git a/drivers/acpi/apei/cper.c b/drivers/acpi/apei/cper.c > index 1e5d8a4..8713229 100644 > --- a/drivers/acpi/apei/cper.c > +++ b/drivers/acpi/apei/cper.c > @@ -250,10 +250,6 @@ static const char *cper_pcie_port_type_strs[] = { > static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie, > const struct acpi_hest_generic_data *gdata) > { > -#ifdef CONFIG_ACPI_APEI_PCIEAER > - struct pci_dev *dev; > -#endif > - > if (pcie->validation_bits & CPER_PCIE_VALID_PORT_TYPE) > printk("%s""port_type: %d, %s\n", pfx, pcie->port_type, > pcie->port_type < ARRAY_SIZE(cper_pcie_port_type_strs) ? > @@ -285,20 +281,6 @@ static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie, > printk( > "%s""bridge: secondary_status: 0x%04x, control: 0x%04x\n", > pfx, pcie->bridge.secondary_status, pcie->bridge.control); > -#ifdef CONFIG_ACPI_APEI_PCIEAER > - dev = pci_get_domain_bus_and_slot(pcie->device_id.segment, > - pcie->device_id.bus, pcie->device_id.function); > - if (!dev) { > - pr_err("PCI AER Cannot get PCI device %04x:%02x:%02x.%d\n", > - pcie->device_id.segment, pcie->device_id.bus, > - pcie->device_id.slot, pcie->device_id.function); > - return; > - } > - if (pcie->validation_bits & CPER_PCIE_VALID_AER_INFO) > - cper_print_aer(pfx, dev, gdata->error_severity, > - (struct aer_capability_regs *) pcie->aer_info); > - pci_dev_put(dev); > -#endif > } > > static const char *apei_estatus_section_flag_strs[] = { > diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c > index d668a8a..f2084b5 100644 > --- a/drivers/acpi/apei/ghes.c > +++ b/drivers/acpi/apei/ghes.c > @@ -454,7 +454,8 @@ static void ghes_do_proc(struct ghes *ghes, > aer_severity = cper_severity_to_aer(sev); > aer_recover_queue(pcie_err->device_id.segment, > pcie_err->device_id.bus, > - devfn, aer_severity); > + devfn, aer_severity, > + pcie_err->aer_info); > } > > } > diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c > index 564d97f..26aec0f 100644 > --- a/drivers/pci/pcie/aer/aerdrv_core.c > +++ b/drivers/pci/pcie/aer/aerdrv_core.c > @@ -582,6 +582,7 @@ struct aer_recover_entry > u8 devfn; > u16 domain; > int severity; > + u8 *regs; > }; > > static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry, > @@ -595,7 +596,7 @@ static DEFINE_SPINLOCK(aer_recover_ring_lock); > static DECLARE_WORK(aer_recover_work, aer_recover_work_func); > > void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, > - int severity) > + int severity, u8 *aer_regs) > { > unsigned long flags; > struct aer_recover_entry entry = { > @@ -603,6 +604,7 @@ void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, > .devfn = devfn, > .domain = domain, > .severity = severity, > + .regs = aer_regs, > }; > > spin_lock_irqsave(&aer_recover_ring_lock, flags); > @@ -629,6 +631,8 @@ static void aer_recover_work_func(struct work_struct *work) > PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn)); > continue; > } > + cper_print_aer("", pdev, entry.severity, > + (struct aer_capability_regs *)entry.regs); > do_recovery(pdev, entry.severity); > pci_dev_put(pdev); > } > diff --git a/include/linux/aer.h b/include/linux/aer.h > index ec10e1b..a5c1583 100644 > --- a/include/linux/aer.h > +++ b/include/linux/aer.h > @@ -53,6 +53,6 @@ extern void cper_print_aer(const char *prefix, struct pci_dev *dev, > int cper_severity, struct aer_capability_regs *aer); > extern int cper_severity_to_aer(int cper_severity); > extern void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, > - int severity); > + int severity, u8 *aer_regs); > #endif //_AER_H_ > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 09, 2013 at 12:01:21AM +0200, Rafael J. Wysocki wrote: > On Wednesday, May 08, 2013 11:15:19 AM Lance Ortiz wrote: > > The following warning was seen on 3.9 when a corrected PCIe error was being > > handled by the AER subsystem. > > > > WARNING: at .../drivers/pci/search.c:214 pci_get_dev_by_id+0x8a/0x90() > > > > This occurred because code was added to the function cper_print_pcie() that > > calls the pci_get_domain_bus_and_slot() function. > > Do you know which commit added that code? 1d5210008bd3a26daf4b06aed9d6c330dd4c83e2 > > cper_print_pcie() is called > > in an interrupt context and pci_get* functions are not supposed to be called > > in that context hence the warning. > > > > The solution is to move the call to cper_print_aer() out of the interrupt > > context and into aer_recover_queue() to avoid any warnings when calling > > pci_get* functions. > > The way the changes are described here isn't particularly clear to me. I'd say > something like > > If cper_print_aer() is called by aer_recover_work_func(), there won't be any > reason to call it from cper_print_pcie() any more, in which case all of the > problematic code needed only to prepare for the cper_print_aer() call, > including the invocation of pci_get_domain_bus_and_slot() causing the warning > to be printed, may be removed from there. Make that happen." > > Also, since aer_recover_work_func() is going to be the only existing caller of > cper_print_aer() after this change, as far as I can say, and it doesn't use the > function's first argument, that argument should be dropped entirely. Hmm, that needs more diddling: AFAICT __ghes_print_estatus() figures out what the prefix is depending on the ->error_severity coming from the acpi_hest_generic_status thing so it probably needs to be handed down or similar... Fun.
Rafael, Thanks for your feedback. > The way the changes are described here isn't particularly clear to me. I will try to make it a little more clear. > Also, since aer_recover_work_func() is going to be the only existing > caller of > cper_print_aer() after this change, as far as I can say, and it doesn't > use the > function's first argument, that argument should be dropped entirely. The truth is, the function cper_print_aer() really needs to be re-written so it is consistent with aer_print_error() in how it outputs information. Right now, the output is formatted very differently. I was planning on doing that at a later date, but fix the warning now. I might add a TODO comment in the code for this. The reason I did not remove the argument in cper_print_aer() is because 'prefix' is used in the call to cper_print_bits(), and I passed through an empty string to make sure that function worked correctly. I can try to clean it up. Lance
On Thursday, May 09, 2013 07:10:36 PM Ortiz, Lance E wrote: > Rafael, > > Thanks for your feedback. > > > The way the changes are described here isn't particularly clear to me. > > I will try to make it a little more clear. Cool, thanks! > > Also, since aer_recover_work_func() is going to be the only existing > > caller of > > cper_print_aer() after this change, as far as I can say, and it doesn't > > use the > > function's first argument, that argument should be dropped entirely. > > The truth is, the function cper_print_aer() really needs to be re-written so > it is consistent with aer_print_error() in how it outputs information. > Right now, the output is formatted very differently. I was planning on doing > that at a later date, but fix the warning now. I might add a TODO comment in > the code for this. Yes, I think that would be OK, depending on the amount of changes actually needed to rework it (if that's not too much, I'd just go straight for the rework, honestly). > The reason I did not remove the argument in cper_print_aer() is because > 'prefix' is used in the call to cper_print_bits(), and I passed through an > empty string to make sure that function worked correctly. I can try to clean > it up. Please do. Thanks, Rafael
diff --git a/drivers/acpi/apei/cper.c b/drivers/acpi/apei/cper.c index 1e5d8a4..8713229 100644 --- a/drivers/acpi/apei/cper.c +++ b/drivers/acpi/apei/cper.c @@ -250,10 +250,6 @@ static const char *cper_pcie_port_type_strs[] = { static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie, const struct acpi_hest_generic_data *gdata) { -#ifdef CONFIG_ACPI_APEI_PCIEAER - struct pci_dev *dev; -#endif - if (pcie->validation_bits & CPER_PCIE_VALID_PORT_TYPE) printk("%s""port_type: %d, %s\n", pfx, pcie->port_type, pcie->port_type < ARRAY_SIZE(cper_pcie_port_type_strs) ? @@ -285,20 +281,6 @@ static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie, printk( "%s""bridge: secondary_status: 0x%04x, control: 0x%04x\n", pfx, pcie->bridge.secondary_status, pcie->bridge.control); -#ifdef CONFIG_ACPI_APEI_PCIEAER - dev = pci_get_domain_bus_and_slot(pcie->device_id.segment, - pcie->device_id.bus, pcie->device_id.function); - if (!dev) { - pr_err("PCI AER Cannot get PCI device %04x:%02x:%02x.%d\n", - pcie->device_id.segment, pcie->device_id.bus, - pcie->device_id.slot, pcie->device_id.function); - return; - } - if (pcie->validation_bits & CPER_PCIE_VALID_AER_INFO) - cper_print_aer(pfx, dev, gdata->error_severity, - (struct aer_capability_regs *) pcie->aer_info); - pci_dev_put(dev); -#endif } static const char *apei_estatus_section_flag_strs[] = { diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index d668a8a..f2084b5 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -454,7 +454,8 @@ static void ghes_do_proc(struct ghes *ghes, aer_severity = cper_severity_to_aer(sev); aer_recover_queue(pcie_err->device_id.segment, pcie_err->device_id.bus, - devfn, aer_severity); + devfn, aer_severity, + pcie_err->aer_info); } } diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c index 564d97f..26aec0f 100644 --- a/drivers/pci/pcie/aer/aerdrv_core.c +++ b/drivers/pci/pcie/aer/aerdrv_core.c @@ -582,6 +582,7 @@ struct aer_recover_entry u8 devfn; u16 domain; int severity; + u8 *regs; }; static DEFINE_KFIFO(aer_recover_ring, struct aer_recover_entry, @@ -595,7 +596,7 @@ static DEFINE_SPINLOCK(aer_recover_ring_lock); static DECLARE_WORK(aer_recover_work, aer_recover_work_func); void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, - int severity) + int severity, u8 *aer_regs) { unsigned long flags; struct aer_recover_entry entry = { @@ -603,6 +604,7 @@ void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, .devfn = devfn, .domain = domain, .severity = severity, + .regs = aer_regs, }; spin_lock_irqsave(&aer_recover_ring_lock, flags); @@ -629,6 +631,8 @@ static void aer_recover_work_func(struct work_struct *work) PCI_SLOT(entry.devfn), PCI_FUNC(entry.devfn)); continue; } + cper_print_aer("", pdev, entry.severity, + (struct aer_capability_regs *)entry.regs); do_recovery(pdev, entry.severity); pci_dev_put(pdev); } diff --git a/include/linux/aer.h b/include/linux/aer.h index ec10e1b..a5c1583 100644 --- a/include/linux/aer.h +++ b/include/linux/aer.h @@ -53,6 +53,6 @@ extern void cper_print_aer(const char *prefix, struct pci_dev *dev, int cper_severity, struct aer_capability_regs *aer); extern int cper_severity_to_aer(int cper_severity); extern void aer_recover_queue(int domain, unsigned int bus, unsigned int devfn, - int severity); + int severity, u8 *aer_regs); #endif //_AER_H_
The following warning was seen on 3.9 when a corrected PCIe error was being handled by the AER subsystem. WARNING: at .../drivers/pci/search.c:214 pci_get_dev_by_id+0x8a/0x90() This occurred because code was added to the function cper_print_pcie() that calls the pci_get_domain_bus_and_slot() function. cper_print_pcie() is called in an interrupt context and pci_get* functions are not supposed to be called in that context hence the warning. The solution is to move the call to cper_print_aer() out of the interrupt context and into aer_recover_queue() to avoid any warnings when calling pci_get* functions. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> --- drivers/acpi/apei/cper.c | 18 ------------------ drivers/acpi/apei/ghes.c | 3 ++- drivers/pci/pcie/aer/aerdrv_core.c | 6 +++++- include/linux/aer.h | 2 +- 4 files changed, 8 insertions(+), 21 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html