[POWERPC] Fix boot failure on POWER6
authorPaul Mackerras <paulus@samba.org>
Tue, 15 Jan 2008 06:29:33 +0000 (17:29 +1100)
committerPaul Mackerras <paulus@samba.org>
Tue, 15 Jan 2008 06:30:58 +0000 (17:30 +1100)
commitdfbe0d3b6be52596b5694b1bb75b19562e769021
tree75e3ef05b6dd8cc7065fe77a05a9cd1b3495619a
parentd262c32a4bcc3e5fda0325a64e53c25fe1e999d7
[POWERPC] Fix boot failure on POWER6

Commit 473980a99316c0e788bca50996375a2815124ce1 added a call to clear
the SLB shadow buffer before registering it.  Unfortunately this means
that we clear out the entries that slb_initialize has previously set in
there.  On POWER6, the hypervisor uses the SLB shadow buffer when doing
partition switches, and that means that after the next partition switch,
each non-boot CPU has no SLB entries to map the kernel text and data,
which causes it to crash.

This fixes it by reverting most of 473980a9 and instead clearing the
3rd entry explicitly in slb_initialize.  This fixes the problem that
473980a9 was trying to solve, but without breaking POWER6.

Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/mm/slb.c
arch/powerpc/platforms/pseries/lpar.c
include/asm-powerpc/mmu-hash64.h