From addb63c18a0d52a9ce2611d039f981f7b6148d2b Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 19 Jun 2017 08:02:28 +0200 Subject: [PATCH] KVM: s390: gaccess: fix real-space designation asce handling for gmap shadows For real-space designation asces the asce origin part is only a token. The asce token origin must not be used to generate an effective address for storage references. This however is erroneously done within kvm_s390_shadow_tables(). Furthermore within the same function the wrong parts of virtual addresses are used to generate a corresponding real address (e.g. the region second index is used as region first index). Both of the above can result in incorrect address translations. Only for real space designations with a token origin of zero and addresses below one megabyte the translation was correct. Furthermore replace a "!asce.r" statement with a "!*fake" statement to make it more obvious that a specific condition has nothing to do with the architecture, but with the fake handling of real space designations. Fixes: 3218f7094b6b ("s390/mm: support real-space for gmap shadows") Cc: David Hildenbrand Cc: stable@vger.kernel.org Signed-off-by: Heiko Carstens Reviewed-by: Martin Schwidefsky Signed-off-by: Christian Borntraeger --- arch/s390/kvm/gaccess.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 9da243d94cc3..3b297fa3aa67 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -977,11 +977,12 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, ptr = asce.origin * 4096; if (asce.r) { *fake = 1; + ptr = 0; asce.dt = ASCE_TYPE_REGION1; } switch (asce.dt) { case ASCE_TYPE_REGION1: - if (vaddr.rfx01 > asce.tl && !asce.r) + if (vaddr.rfx01 > asce.tl && !*fake) return PGM_REGION_FIRST_TRANS; break; case ASCE_TYPE_REGION2: @@ -1009,8 +1010,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, union region1_table_entry rfte; if (*fake) { - /* offset in 16EB guest memory block */ - ptr = ptr + ((unsigned long) vaddr.rsx << 53UL); + ptr += (unsigned long) vaddr.rfx << 53; rfte.val = ptr; goto shadow_r2t; } @@ -1036,8 +1036,7 @@ shadow_r2t: union region2_table_entry rste; if (*fake) { - /* offset in 8PB guest memory block */ - ptr = ptr + ((unsigned long) vaddr.rtx << 42UL); + ptr += (unsigned long) vaddr.rsx << 42; rste.val = ptr; goto shadow_r3t; } @@ -1064,8 +1063,7 @@ shadow_r3t: union region3_table_entry rtte; if (*fake) { - /* offset in 4TB guest memory block */ - ptr = ptr + ((unsigned long) vaddr.sx << 31UL); + ptr += (unsigned long) vaddr.rtx << 31; rtte.val = ptr; goto shadow_sgt; } @@ -1101,8 +1099,7 @@ shadow_sgt: union segment_table_entry ste; if (*fake) { - /* offset in 2G guest memory block */ - ptr = ptr + ((unsigned long) vaddr.sx << 20UL); + ptr += (unsigned long) vaddr.sx << 20; ste.val = ptr; goto shadow_pgt; }