mii/qemu
1
0
Fork 0
mirror of https://github.com/mii443/qemu.git synced 2025-12-03 11:08:25 +00:00
Code Issues Packages Projects Releases Wiki Activity

address_space_read: address_space_to_flatview needs RCU lock

Browse Source 
address_space_read is calling address_space_to_flatview but it can
be called outside the RCU lock.  To fix it, push the rcu_read_lock/unlock
pair up from flatview_read_full to address_space_read's constant size
fast path and address_space_read_full.

Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini
2018-03-05 00:19:49 +01:00
parent 4c6ebbb364
commit b2a44fcad7
2 changed files with 35 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
exec.c
View File

@@ -2616,6 +2616,8 @@ static const MemoryRegionOps watch_mem_ops = {
},
};
static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf, int len);
static MemTxResult flatview_write(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
const uint8_t *buf, int len);
static bool flatview_access_valid(FlatView *fv, hwaddr addr, int len,
@@ -3165,24 +3167,18 @@ MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
return result;
}
MemTxResult flatview_read_full(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf, int len)
/* Called from RCU critical section. */
static MemTxResult flatview_read(FlatView *fv, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf, int len)
{
hwaddr l;
hwaddr addr1;
MemoryRegion *mr;
MemTxResult result = MEMTX_OK;
if (len > 0) {
rcu_read_lock();
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false);
result = flatview_read_continue(fv, addr, attrs, buf, len,
addr1, l, mr);
rcu_read_unlock();
}
return result;
l = len;
mr = flatview_translate(fv, addr, &addr1, &l, false);
return flatview_read_continue(fv, addr, attrs, buf, len,
addr1, l, mr);
}
static MemTxResult flatview_rw(FlatView *fv, hwaddr addr, MemTxAttrs attrs,
@@ -3203,6 +3199,22 @@ MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
addr, attrs, buf, len, is_write);
}
MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs, uint8_t *buf, int len)
{
MemTxResult result = MEMTX_OK;
FlatView *fv;
if (len > 0) {
rcu_read_lock();
fv = address_space_to_flatview(as);
result = flatview_read(fv, addr, attrs, buf, len);
rcu_read_unlock();
}
return result;
}
MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
MemTxAttrs attrs,
const uint8_t *buf, int len)