On 08/07/15 13:37, Scott Wood wrote: > On Wed, 2015-07-08 at 13:29 +1000, Samuel Mendoza-Jonas wrote: >> Older big-endian ppc64 kernels don't include the FIXUP_ENDIAN check, >> meaning if we kexec from a little-endian kernel the target kernel will >> fail to boot. >> Returning to big-endian before we enter the target kernel ensures that >> the target kernel can boot whether or not it includes FIXUP_ENDIAN. >> >> Signed-off-by: Samuel Mendoza-Jonas <sam...@au1.ibm.com> >> --- >> V2: As suggested by Anton take advantage of the rfid call and switch off >> MSR_LE and branch to the target kernel in the same step. >> >> kexec_trampoline.S | 11 +++++++++-- >> 1 file changed, 9 insertions(+), 2 deletions(-) >> >> diff --git a/kexec_trampoline.S b/kexec_trampoline.S >> index a3eb314..3751112 100644 >> --- a/kexec_trampoline.S >> +++ b/kexec_trampoline.S >> @@ -88,8 +88,15 @@ start: >> >> li r5,0 >> >> - mtctr r4 >> - bctr >> + mtsrr0 r4 >> + >> + mfmsr r5 >> + clrrdi r5,r5,1 /* Clear MSR_LE */ >> + mtsrr1 r5 >> + >> + li r5,0 >> + >> + rfid > > Is kexec-lite meant to be specific to book3s-64? The README just says "A > simple kexec for flattened device tree platforms" and I see a __powerpc64__ > ifdef in kexec_trampoline.S (but not in the above patch)... > > -Scott >
I believe that particular ifdef is to check if we're little-endian when reading the device tree, but that's still a good point - I'll check with Anton. -- ----------- LTC Ozlabs IBM _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
