Comment 13 for bug 1830872

Revision history for this message
Igor (imammedo) wrote : Re: [Qemu-devel] [RFC PATCH] cputlb: use uint64_t for interim values for unaligned load

On Mon, 3 Jun 2019 16:01:20 +0100
Alex Bennée <email address hidden> wrote:

> When running on 32 bit TCG backends a wide unaligned load ends up
> truncating data before returning to the guest. We specifically have
> the return type as uint64_t to avoid any premature truncation so we
> should use the same for the interim types.
>
> Hopefully fixes #1830872
>
> Signed-off-by: Alex Bennée <email address hidden>

Fixes arm/virt bios-tables-test for me, so

Tested-by: Igor Mammedov <email address hidden>

> ---
> accel/tcg/cputlb.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
> index cdcc3771020..b796ab1cbea 100644
> --- a/accel/tcg/cputlb.c
> +++ b/accel/tcg/cputlb.c
> @@ -1303,7 +1303,7 @@ load_helper(CPUArchState *env, target_ulong addr, TCGMemOpIdx oi,
> && unlikely((addr & ~TARGET_PAGE_MASK) + size - 1
> >= TARGET_PAGE_SIZE)) {
> target_ulong addr1, addr2;
> - tcg_target_ulong r1, r2;
> + uint64_t r1, r2;
> unsigned shift;
> do_unaligned_access:
> addr1 = addr & ~(size - 1);