nfit: disable vendor specific commands

Module option to limit userspace to the publicly defined command set.
For cases where private DIMM commands may be interfering with the
kernel's handling of DIMM state this option can be set to block vendor
specific commands.

Cc: Jerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index b85a46873228eb13a02839be029e8b18a2336354..ad4fc869fbb70f83a9c8796ee917573eb60e5cca 100644 (file)
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -45,6 +45,11 @@ module_param(scrub_overflow_abort, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(scrub_overflow_abort,
                "Number of times we overflow ARS results before abort");
 
+static bool disable_vendor_specific;
+module_param(disable_vendor_specific, bool, S_IRUGO);
+MODULE_PARM_DESC(disable_vendor_specific,
+               "Limit commands to the publicly specified set\n");
+
 static struct workqueue_struct *nfit_wq;
 
 struct nfit_table_prev {
@@ -989,13 +994,17 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
 
        /* limit the supported commands to those that are publicly documented */
        nfit_mem->family = i;
-       if (nfit_mem->family == NVDIMM_FAMILY_INTEL)
+       if (nfit_mem->family == NVDIMM_FAMILY_INTEL) {
                dsm_mask = 0x3fe;
-       else if (nfit_mem->family == NVDIMM_FAMILY_HPE1)
+               if (disable_vendor_specific)
+                       dsm_mask &= ~(1 << ND_CMD_VENDOR);
+       } else if (nfit_mem->family == NVDIMM_FAMILY_HPE1)
                dsm_mask = 0x1c3c76;
-       else if (nfit_mem->family == NVDIMM_FAMILY_HPE2)
+       else if (nfit_mem->family == NVDIMM_FAMILY_HPE2) {
                dsm_mask = 0x1fe;
-       else {
+               if (disable_vendor_specific)
+                       dsm_mask &= ~(1 << 8);
+       } else {
                dev_err(dev, "unknown dimm command family\n");
                nfit_mem->family = -1;
                return force_enable_dimms ? 0 : -ENODEV;