On Wed, Jan 20, 2016 at 12:16 PM, Dan Williams <dan.j.willi...@intel.com> wrote: > On Wed, Jan 20, 2016 at 12:08 PM, Dan Williams <dan.j.willi...@intel.com> > wrote: >> On Wed, Jan 20, 2016 at 12:01 PM, Larry Finger >> <larry.fin...@lwfinger.net> wrote: >>> My PowerBook G4 Aluminum with a 32-bit PPC processor fails to boot for the >>> 4.4-git series. The problem was bisected to commit 21266be. It took a while >>> to figure out why a commit that only rearranges the Kconfig files could >>> cause the problem. >>> >>> The answer came when I read the commit message for 90a545e98126 and saw that >>> "Recompiling with CONFIG_IO_STRICT_DEVMEM=n" might be necessary. After I >>> made that change, the system boots. >>> >>> If it is the graphics hardware driver at fault, the VGA controller is listed >>> as an ATI RV350 [Mobility Radeon 9600 M10] with PCI ID 1002:4350. It uses >>> radeon as the driver. >>> >>> I'm not sure if this is a bug in the configuration, but I know that >>> selecting the default answer to all the new configuration parameters leaves >>> me with a machine that is unbootable. >> >> I agree that the default configuration should remain bootable. I'll >> send a change that does not force that default. >> >> Thanks for the report and sorry for the inconvenience. > > Are you sure that the bisect is pointing to "21266be9ed54 arch: > consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug" and not > "90a545e98126 restrict /dev/mem to idle io memory ranges"? The > default for CONFIG_STRICT_DEVM should be unchanged in 21266be9ed54, > it's not until 90a545e98126 that I would expect a behavior change.
Sorry for the mail flurry... if you can verify that the following change resolves this problem I'll send it up: diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index f75a33f29f6e..7d0b49c536c5 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1919,7 +1919,6 @@ config STRICT_DEVMEM config IO_STRICT_DEVMEM bool "Filter I/O access to /dev/mem" depends on STRICT_DEVMEM - default STRICT_DEVMEM ---help--- If this option is disabled, you allow userspace (root) access to all io-memory regardless of whether a driver is actively using that