Re: [PATCH 1/2] libnvdimm: fix clear length of nvdimm_forget_poison()

From: Dan Williams
Date: Fri Apr 28 2017 - 18:39:11 EST


On Fri, Apr 28, 2017 at 3:29 PM, Kani, Toshimitsu <toshi.kani@xxxxxxx> wrote:
> On Fri, 2017-04-28 at 14:48 -0700, Dan Williams wrote:
>> On Thu, Apr 27, 2017 at 3:57 PM, Toshi Kani <toshi.kani@xxxxxxx>
>> wrote:
>> > ND_CMD_CLEAR_ERROR command returns 'clear_err.cleared', the length
>> > of error actually cleared, which may be smaller than its requested
>> > 'len'.
>> >
>> > Change nvdimm_clear_poison() to call nvdimm_forget_poison() with
>> > 'clear_err.cleared' when this value is valid.
>> >
>> > Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx>
>> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
>> > Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
>> > Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
>> > ---
>> > Based on 'libnvdimm-for-next'.
>> > ---
>> > drivers/nvdimm/bus.c | 4 +++-
>> > 1 file changed, 3 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
>> > index d214ac44..43ddfd4 100644
>> > --- a/drivers/nvdimm/bus.c
>> > +++ b/drivers/nvdimm/bus.c
>> > @@ -219,7 +219,9 @@ long nvdimm_clear_poison(struct device *dev,
>> > phys_addr_t phys,
>> > if (cmd_rc < 0)
>> > return cmd_rc;
>> >
>> > - nvdimm_forget_poison(nvdimm_bus, phys, len);
>> > + if (clear_err.cleared > 0)
>> > + nvdimm_forget_poison(nvdimm_bus, phys,
>> > clear_err.cleared);
>> > +
>> > return clear_err.cleared;
>>
>> Looks, good we need to mark this for -stable since the bug is also
>> present in current mainline.
>>
>> Fixes: e046114af5fc ("libnvdimm: clear the internal poison_list when
>> clearing badblocks")
>
> Shall I send a patch based on the current mainline with cc to -stable?
> The func name is nvdimm_clear_from_poison_list() in the mainline.

I thinks it's too late to get a fix into 4.11, especially when this
went in broken and not a regression. I'll just tag this for -stable
and handle the backport manually.