| Message ID | 1829835.4TBEQGhjkq@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
On Thu, Nov 29, 2012 at 4:10 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > During resume from system suspend the 'data' field of > struct pnp_dev in pnpacpi_set_resources() may be a stale pointer, > due to removal of the associated ACPI device node object in the > previous suspend-resume cycle. This happens, for example, if a > dockable machine is booted in the docking station and then suspended > and resumed and suspended again. If that happens, > pnpacpi_build_resource_template() called from pnpacpi_set_resources() > attempts to use that pointer and crashes. > > However, pnpacpi_set_resources() actually checks the device's ACPI > handle, attempts to find the ACPI device node object attached to it > and returns an error code if that fails, so in fact it knows what the > correct value of dev->data should be. Use this observation to update > dev->data with the correct value if necessary and dump a call trace > if that's the case (once). > > We still need to fix the root cause of this issue, but preventing > systems from crashing because of it is an improvement too. > > Reported-and-tested-by: Zdenek Kabelac <zdenek.kabelac@gmail.com> > References: https://bugzilla.kernel.org/show_bug.cgi?id=51071 > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Any reason why this shouldn't go into stable releases? -- Shuah -- 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, Nov 29, 2012 at 4:51 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > On Thursday, November 29, 2012 04:25:20 PM Shuah Khan wrote: >> On Thu, Nov 29, 2012 at 4:10 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote: >> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> > >> > During resume from system suspend the 'data' field of >> > struct pnp_dev in pnpacpi_set_resources() may be a stale pointer, >> > due to removal of the associated ACPI device node object in the >> > previous suspend-resume cycle. This happens, for example, if a >> > dockable machine is booted in the docking station and then suspended >> > and resumed and suspended again. If that happens, >> > pnpacpi_build_resource_template() called from pnpacpi_set_resources() >> > attempts to use that pointer and crashes. >> > >> > However, pnpacpi_set_resources() actually checks the device's ACPI >> > handle, attempts to find the ACPI device node object attached to it >> > and returns an error code if that fails, so in fact it knows what the >> > correct value of dev->data should be. Use this observation to update >> > dev->data with the correct value if necessary and dump a call trace >> > if that's the case (once). >> > >> > We still need to fix the root cause of this issue, but preventing >> > systems from crashing because of it is an improvement too. >> > >> > Reported-and-tested-by: Zdenek Kabelac <zdenek.kabelac@gmail.com> >> > References: https://bugzilla.kernel.org/show_bug.cgi?id=51071 >> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >> >> Any reason why this shouldn't go into stable releases? > > Yes, it can go to -stable. This is just a patch, not a git commit. I can > still add the "stable" tag to it when it goes to git. :-) > Good. This patch applies just fine to 3.0.x, 3.4.x and 3.6.x for what its worth. That's how far I have gotten so far and getting ready to do compile tests on these. -- Shuah -- 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 Thursday, November 29, 2012 04:25:20 PM Shuah Khan wrote: > On Thu, Nov 29, 2012 at 4:10 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote: > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > During resume from system suspend the 'data' field of > > struct pnp_dev in pnpacpi_set_resources() may be a stale pointer, > > due to removal of the associated ACPI device node object in the > > previous suspend-resume cycle. This happens, for example, if a > > dockable machine is booted in the docking station and then suspended > > and resumed and suspended again. If that happens, > > pnpacpi_build_resource_template() called from pnpacpi_set_resources() > > attempts to use that pointer and crashes. > > > > However, pnpacpi_set_resources() actually checks the device's ACPI > > handle, attempts to find the ACPI device node object attached to it > > and returns an error code if that fails, so in fact it knows what the > > correct value of dev->data should be. Use this observation to update > > dev->data with the correct value if necessary and dump a call trace > > if that's the case (once). > > > > We still need to fix the root cause of this issue, but preventing > > systems from crashing because of it is an improvement too. > > > > Reported-and-tested-by: Zdenek Kabelac <zdenek.kabelac@gmail.com> > > References: https://bugzilla.kernel.org/show_bug.cgi?id=51071 > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Any reason why this shouldn't go into stable releases? Yes, it can go to -stable. This is just a patch, not a git commit. I can still add the "stable" tag to it when it goes to git. :-) Thanks, Rafael
Index: linux/drivers/pnp/pnpacpi/core.c =================================================================== --- linux.orig/drivers/pnp/pnpacpi/core.c +++ linux/drivers/pnp/pnpacpi/core.c @@ -95,6 +95,9 @@ static int pnpacpi_set_resources(struct return -ENODEV; } + if (WARN_ON_ONCE(acpi_dev != dev->data)) + dev->data = acpi_dev; + ret = pnpacpi_build_resource_template(dev, &buffer); if (ret) return ret;