Re: [Qemu-devel] [PATCH 6/7] address_space_map: address_space_to_flatview needs RCU lock
On 05/03/18 19:36, Paolo Bonzini wrote: > address_space_map is calling address_space_to_flatview but it can > be called outside the RCU lock. The function itself is calling > rcu_read_lock/rcu_read_unlock, just in the wrong place, so the > fix is easy. > > Cc: qemu-sta...@nongnu.org > Signed-off-by: Paolo BonziniReviewed-by: Alexey Kardashevskiy > --- > exec.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/exec.c b/exec.c > index 177583c2ee..070eaff3e7 100644 > --- a/exec.c > +++ b/exec.c > @@ -3464,7 +3464,7 @@ void *address_space_map(AddressSpace *as, > hwaddr l, xlat; > MemoryRegion *mr; > void *ptr; > -FlatView *fv = address_space_to_flatview(as); > +FlatView *fv; > > if (len == 0) { > return NULL; > @@ -3472,6 +3472,7 @@ void *address_space_map(AddressSpace *as, > > l = len; > rcu_read_lock(); > +fv = address_space_to_flatview(as); > mr = flatview_translate(fv, addr, , , is_write); > > if (!memory_access_is_direct(mr, is_write)) { > -- Alexey
[Qemu-devel] [PATCH 6/7] address_space_map: address_space_to_flatview needs RCU lock
address_space_map is calling address_space_to_flatview but it can be called outside the RCU lock. The function itself is calling rcu_read_lock/rcu_read_unlock, just in the wrong place, so the fix is easy. Cc: qemu-sta...@nongnu.org Signed-off-by: Paolo Bonzini--- exec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/exec.c b/exec.c index 177583c2ee..070eaff3e7 100644 --- a/exec.c +++ b/exec.c @@ -3464,7 +3464,7 @@ void *address_space_map(AddressSpace *as, hwaddr l, xlat; MemoryRegion *mr; void *ptr; -FlatView *fv = address_space_to_flatview(as); +FlatView *fv; if (len == 0) { return NULL; @@ -3472,6 +3472,7 @@ void *address_space_map(AddressSpace *as, l = len; rcu_read_lock(); +fv = address_space_to_flatview(as); mr = flatview_translate(fv, addr, , , is_write); if (!memory_access_is_direct(mr, is_write)) { -- 2.14.3