KVM: PPC: Book3S PR: Rework SLB switching code

On LPAR guest systems Linux enables the shadow SLB to indicate to the
hypervisor a number of SLB entries that always have to be available.

Today we go through this shadow SLB and disable all ESID's valid bits.
However, pHyp doesn't like this approach very much and honors us with
fancy machine checks.

Fortunately the shadow SLB descriptor also has an entry that indicates
the number of valid entries following. During the lifetime of a guest
we can just swap that value to 0 and don't have to worry about the
SLB restoration magic.

While we're touching the code, let's also make it more readable (get
rid of rldicl), allow it to deal with a dynamic number of bolted
SLB entries and only do shadow SLB swizzling on LPAR systems.

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 9d1d33cd2be5..964a5f61488a 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -97,7 +97,7 @@ static inline void create_shadowed_slbe(unsigned long ea, int ssize,
 static void __slb_flush_and_rebolt(void)
 {
 	/* If you change this make sure you change SLB_NUM_BOLTED
-	 * appropriately too. */
+	 * and PR KVM appropriately too. */
 	unsigned long linear_llp, vmalloc_llp, lflags, vflags;
 	unsigned long ksp_esid_data, ksp_vsid_data;