Skip to contentSkip to conversation

vhost: fix dirty page handling

PATCH In review Michael S. Tsirkin 3 participants 3 messages Mar 16, 2011

lore
Share & tools
lore

Michael S. Tsirkin

author
#0 lore raw

PATCH 1/1 vhost: fix dirty page handling

vhost was passing a physical address to cpu_physical_memory_set_dirty, which is wrong: we need to translate to ram address first.

Signed-off-by Michael S. Tsirkin <[email protected]>

Note: this lead to crashes during migration, so the patch is needed on the stable branch too.

---
 hw/vhost.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
hw/vhost.c +3 -1
index aaa34e4..97a1299 100644
@@ -49,8 +49,10 @@ static void vhost_dev_sync_region(struct vhost_dev *dev,
         log = __sync_fetch_and_and(from, 0);
         while ((bit = sizeof(log) > sizeof(int) ?
                 ffsll(log) : ffs(log))) {
+            ram_addr_t ram_addr;
             bit -= 1;
-            cpu_physical_memory_set_dirty(addr + bit * VHOST_LOG_PAGE);
+            ram_addr = cpu_get_physical_page_desc(addr + bit * VHOST_LOG_PAGE);
+            cpu_physical_memory_set_dirty(ram_addr);
             log &= ~(0x1ull << bit);
         }
         addr += VHOST_LOG_CHUNK;
Signature · 1 line
1.7.3.2.91.g446ac
Reviewed-by on v1 1/1
#1 lore raw
Quoted 7 lines · Michael S. Tsirkin

vhost was passing a physical address to cpu_physical_memory_set_dirty, which is wrong: we need to translate to ram address first.

Signed-off-by Michael S. Tsirkin <[email protected]>

Note: this lead to crashes during migration, so the patch is needed on the stable branch too.

Reviewed-by Juan Quintela <[email protected]>

We have been having strange migration corruptions for some time, this can explain what was going on.

Quoted 10 lines
---
 hw/vhost.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
hw/vhost.c +0 -0
index aaa34e4..97a1299 100644
@@ -49,8 +49,10 @@ static void vhost_dev_sync_region(struct vhost_dev *dev,
         log = __sync_fetch_and_and(from, 0);

hw/vhost.c static void vhost_dev_sync_region(struct vhost_dev *dev, · line 58

Quoted 10 lines
hw/vhost.c +3 -1
         while ((bit = sizeof(log) > sizeof(int) ?
                 ffsll(log) : ffs(log))) {
+            ram_addr_t ram_addr;
             bit -= 1;
-            cpu_physical_memory_set_dirty(addr + bit * VHOST_LOG_PAGE);
+            ram_addr = cpu_get_physical_page_desc(addr + bit * VHOST_LOG_PAGE);
+            cpu_physical_memory_set_dirty(ram_addr);
             log &= ~(0x1ull << bit);
         }
         addr += VHOST_LOG_CHUNK;

<#secure method=pgpmime mode=sign>

Reviewed-by on v1 1/1
#2 lore raw
In reply to Michael S. Tsirkin
Quoted 18 lines · Michael S. Tsirkin

vhost was passing a physical address to cpu_physical_memory_set_dirty, which is wrong: we need to translate to ram address first.

Signed-off-by Michael S. Tsirkin <[email protected]>

Note: this lead to crashes during migration, so the patch is needed on the stable branch too.

---
 hw/vhost.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
hw/vhost.c +0 -0
index aaa34e4..97a1299 100644
@@ -49,8 +49,10 @@ static void vhost_dev_sync_region(struct vhost_dev *dev,
         log = __sync_fetch_and_and(from, 0);

hw/vhost.c static void vhost_dev_sync_region(struct vhost_dev *dev, · line 58

Quoted 10 lines
hw/vhost.c +3 -1
         while ((bit = sizeof(log) > sizeof(int) ?
                 ffsll(log) : ffs(log))) {
+            ram_addr_t ram_addr;
             bit -= 1;
-            cpu_physical_memory_set_dirty(addr + bit * VHOST_LOG_PAGE);
+            ram_addr = cpu_get_physical_page_desc(addr + bit * VHOST_LOG_PAGE);
+            cpu_physical_memory_set_dirty(ram_addr);
             log &= ~(0x1ull << bit);
         }
         addr += VHOST_LOG_CHUNK;
Reviewed-by Alex Williamson <[email protected]>