| Subject | Re: [ 045/262] ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores | From | Ben Hutchings <> | Date | Sat, 29 Sep 2012 14:25:50 +0200 |
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On Fri, 2012-09-28 at 11:49 -0700, Greg Kroah-Hartman wrote: > From: Greg KH <gregkh@linuxfoundation.org> > > 3.5-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Will Deacon <will.deacon@arm.com> > > commit dbece45894d3ab1baac15a96dc4e1e8e23f64a93 upstream. > > When enabling the MMU for ARMv7 CPUs, the decompressor does not touch > the ttbcr register, assuming that it will be zeroed (N == 0, EAE == 0). > Given that only EAE is defined as 0 for non-secure copies of the > register (and a bootloader such as kexec may leave it set to 1 anyway), > we should ensure that we reset the register ourselves before turning on > the MMU. > > This patch zeroes TTBCR.EAE and TTBCR.N prior to enabling the MMU for > ARMv7 cores in the decompressor, configuring us exclusively for 32-bit > translation tables via TTBR0. > > Acked-by: Nicolas Pitre <nico@linaro.org> > Signed-off-by: Matthew Leach <matthew.leach@arm.com> > Signed-off-by: Will Deacon <will.deacon@arm.com> > Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [...]
Is this also needed for earlier kernel versions? If so, can you provide a backported version?
Ben.
-- Ben Hutchings Usenet is essentially a HUGE group of people passing notes in class. - Rachel Kadel, `A Quick Guide to Newsgroup Etiquette' [unhandled content-type:application/pgp-signature] |