There is a small window whereby ARS scan requests can schedule work that userspace will miss when polling scrub_show. Hold the init_mutex lock over calls to report the status to close this potential escape. Also, make sure that requests to cancel the ARS workqueue are treated as an idle event. Cc: <stable@xxxxxxxxxxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> Fixes: 37b137ff8c83 ("nfit, libnvdimm: allow an ARS scrub...") Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- drivers/acpi/nfit/core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index ea9f3e727fef..2a1fc3817a81 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -1249,8 +1249,11 @@ static ssize_t scrub_show(struct device *dev, if (nd_desc) { struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc); + mutex_lock(&acpi_desc->init_mutex); rc = sprintf(buf, "%d%s", acpi_desc->scrub_count, - (work_busy(&acpi_desc->work)) ? "+\n" : "\n"); + work_busy(&acpi_desc->work) + && !acpi_desc->cancel ? "+\n" : "\n"); + mutex_unlock(&acpi_desc->init_mutex); } device_unlock(dev); return rc; -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html