On 2012-03-29 at 23:39:57 +0200, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Thu, Mar 29, 2012 at 04:02:07PM -0400, Yuriy Kozlov wrote: > > On Thursday, March 29, 2012 12:47:11 Greg Kroah-Hartman wrote: > > > On Thu, Mar 29, 2012 at 09:38:55PM +0200, Tobias Klauser wrote: > > > > On 2012-03-29 at 18:13:37 +0200, Greg Kroah-Hartman > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > On Thu, Mar 29, 2012 at 09:55:27AM +0200, Tobias Klauser wrote: > > > > > > From: Yuriy Kozlov <ykozlov@xxxxxxxxxx> > > > > > > > > > > > > Follow altera_jtag_uart. This fixes a crash if there is a mistake in > > > > > > the DTS.> > > > > > > Is this something you have seen in the wild? Is this something to be > > > > > backported to stable kernels? > > > > > > > > Not that I know of. But nevertheless it might be worthwhile. Shall I > > > > send the patch again with Cc: stable@xxxxxxxxxx? > > > > > > Nope, I can add it. > > > > > > But, if this isn't something that you have seen, why is it needed to be > > > checked for? What is this making work properly that isn't working > > > properly now? > > > > > > thanks, > > > > > > greg k-h > > > > The driver is designed to use Device Tree to get hardware information, so > > platp (platform_data) is usually NULL. platform_data is still used as a > > fallback mechanism. The problem arises when the device is in the DT, but is > > missing a required property (address or irq). The driver falls back to > > looking for it in the null platp and panics. The function actually already > > checks platp for other properties later on, but under this condition it tried > > to dereference it before the null checks. > > And again, does this happen today in the 3.4-rc1 kernel? 3.3? 3.2? > 3.0? Something else? It's present in all of them, since 2.6.37 when devicetree support for the driver was added. So it could potentially be triggered in all of them. > If not, then why make this change? If so, it needs to go to older > kernels, right? If Yuriy has seen this in the wild, I'd suggest it should got in then. Please let me know if I should redo the patch against the older version. Thanks a lot Tobias -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
