Mailing List Archive

commit 37c853a0bcb214f3de66cc44622287ef89cb51d1
Author: Roger Pau Monné <roger.pau@citrix.com>
AuthorDate: Tue Jul 7 15:23:26 2020 +0200
Commit: Jan Beulich <jbeulich@suse.com>
CommitDate: Tue Jul 7 15:23:26 2020 +0200

vtd: don't assume addresses are aligned in sync_cache

Current code in sync_cache assume that the address passed in is
aligned to a cache line size. Fix the code to support passing in
arbitrary addresses not necessarily aligned to a cache line size.

This is part of XSA-321.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: b6d9398144f21718d25daaf8d72669a75592abc5
master date: 2020-07-07 14:39:05 +0200
---
xen/drivers/passthrough/vtd/iommu.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index facd84ffc8..270eb1c31a 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -161,8 +161,8 @@ static int iommus_incoherent;

static void sync_cache(const void *addr, unsigned int size)
{
- int i;
- static unsigned int clflush_size = 0;
+ static unsigned long clflush_size = 0;
+ const void *end = addr + size;

if ( !iommus_incoherent )
return;
@@ -170,8 +170,9 @@ static void sync_cache(const void *addr, unsigned int size)
if ( clflush_size == 0 )
clflush_size = get_cache_line_size();

- for ( i = 0; i < size; i += clflush_size )
- cacheline_flush((char *)addr + i);
+ addr -= (unsigned long)addr & (clflush_size - 1);
+ for ( ; addr < end; addr += clflush_size )
+ cacheline_flush((char *)addr);
}

/* Allocate page table, return its machine address */
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.11