On 09/19/2018 11:12 AM, Dave Jiang wrote:
> During fakenuma processing in numa_emulation(), pi gets passed in and
> processed as new fake numa nodes are being split out. Once the original
> memory region is proccessed, it gets removed from the pi by
> numa_remove_memblk_from() in emu_setup_memblk(). So entry 0 gets deleted
> and the rest of the entries get moved up. Therefore we should always pass
> in entry 0 for the next entry to process.
>
> Fixes: 1f6a2c6d9f121 ("x86/numa_emulation: Introduce uniform split
> capability")
>
> Cc: Dan Williams <dan.j.willi...@intel.com>
> Signed-off-by: Dave Jiang <dave.ji...@intel.com>
> Reviewed-by: Dan Williams <dan.j.willi...@intel.com>
Ingo,
Is this ok to make 4.19-rc as a fix? Thanks!
> ---
>
> V2:
> - Add comment for the code change (Dan)
>
> arch/x86/mm/numa_emulation.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
> index b54d52a2d00a..d71d72cf6c66 100644
> --- a/arch/x86/mm/numa_emulation.c
> +++ b/arch/x86/mm/numa_emulation.c
> @@ -400,9 +400,17 @@ void __init numa_emulation(struct numa_meminfo
> *numa_meminfo, int numa_dist_cnt)
> n = simple_strtoul(emu_cmdline, &emu_cmdline, 0);
> ret = -1;
> for_each_node_mask(i, physnode_mask) {
> + /*
> + * The reason we pass in blk[0] is due to
> + * numa_remove_memblk_from() called by
> + * emu_setup_memblk() will delete entry 0
> + * and then move everything else up in the pi.blk
> + * array. Therefore we should always be looking
> + * at blk[0].
> + */
> ret = split_nodes_size_interleave_uniform(&ei, &pi,
> - pi.blk[i].start, pi.blk[i].end, 0,
> - n, &pi.blk[i], nid);
> + pi.blk[0].start, pi.blk[0].end, 0,
> + n, &pi.blk[0], nid);
> if (ret < 0)
> break;
> if (ret < n) {
>
