| Message ID | 20160609155617.6650-1-anthony.perard@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/06/2016 17:56, Anthony PERARD wrote: > Since f615f39 (exec: remove ram_addr argument from > qemu_ram_block_from_host), migration under Xen is likely to fail, with a > SEGV of QEMU. But the commit only reveal a bug with the calculation of > the offset value in qemu_ram_block_from_host(). > > This patch calculates the offset from the ram_addr as > qemu_ram_addr_from_host() will later calculate the ram_addr from the > offset. > > Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> > --- > exec.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/exec.c b/exec.c > index f2c9e37..f13106d 100644 > --- a/exec.c > +++ b/exec.c > @@ -1935,7 +1935,7 @@ RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset, > ram_addr = xen_ram_addr_from_mapcache(ptr); > block = qemu_get_ram_block(ram_addr); > if (block) { > - *offset = (host - block->host); > + *offset = ram_addr - block->offset; > } > rcu_read_unlock(); > return block; > Acked-by: Paolo Bonzini <pbonzini@redhat.com> Feel free to send a pull request yourself! Thanks, and sorry for the breakage. Indeed the broken code comes from commit 422148d3e56c3c9a07c0cf36c1e0a0b76f09c357. Paolo
diff --git a/exec.c b/exec.c index f2c9e37..f13106d 100644 --- a/exec.c +++ b/exec.c @@ -1935,7 +1935,7 @@ RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset, ram_addr = xen_ram_addr_from_mapcache(ptr); block = qemu_get_ram_block(ram_addr); if (block) { - *offset = (host - block->host); + *offset = ram_addr - block->offset; } rcu_read_unlock(); return block;
Since f615f39 (exec: remove ram_addr argument from qemu_ram_block_from_host), migration under Xen is likely to fail, with a SEGV of QEMU. But the commit only reveal a bug with the calculation of the offset value in qemu_ram_block_from_host(). This patch calculates the offset from the ram_addr as qemu_ram_addr_from_host() will later calculate the ram_addr from the offset. Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> --- exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)