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| author | Dan Williams <dan.j.williams@intel.com> | 2019-02-03 22:17:27 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2019-02-13 07:14:15 +0300 |
| commit | 0171b6b78131110a6870d4b7296bc9dfc392116a (patch) | |
| tree | c2286a77005b66fe1895a0ba885ada2864a6b05a /drivers/acpi | |
| parent | d5d30d5a5c60628de5e77e3f292a8f9012d51350 (diff) | |
| download | linux-0171b6b78131110a6870d4b7296bc9dfc392116a.tar.xz | |
acpi/nfit: Require opt-in for read-only label configurations
Recent fixes to command handling enabled Linux to read label
configurations that it could not before. Unfortunately that means that
configurations that were operating in label-less mode will be broken as
the kernel ignores the existing namespace configuration and tries to
honor the new found labels.
Fortunately this seems limited to a case where Linux can quirk the
behavior and maintain the existing label-less semantics by default.
When the platform does not emit an _LSW method, disable all label access
methods. Provide a 'force_labels' module parameter to allow read-only
label operation.
Fixes: 11189c1089da ("acpi/nfit: Fix command-supported detection")
Reported-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/nfit/core.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 811c399a3a76..5b5e802de7b8 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -56,6 +56,10 @@ static bool no_init_ars; module_param(no_init_ars, bool, 0644); MODULE_PARM_DESC(no_init_ars, "Skip ARS run at nfit init time"); +static bool force_labels; +module_param(force_labels, bool, 0444); +MODULE_PARM_DESC(force_labels, "Opt-in to labels despite missing methods"); + LIST_HEAD(acpi_descs); DEFINE_MUTEX(acpi_desc_lock); @@ -1916,6 +1920,19 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc, dev_dbg(dev, "%s: has _LSW\n", dev_name(&adev_dimm->dev)); set_bit(NFIT_MEM_LSW, &nfit_mem->flags); } + + /* + * Quirk read-only label configurations to preserve + * access to label-less namespaces by default. + */ + if (!test_bit(NFIT_MEM_LSW, &nfit_mem->flags) + && !force_labels) { + dev_dbg(dev, "%s: No _LSW, disable labels\n", + dev_name(&adev_dimm->dev)); + clear_bit(NFIT_MEM_LSR, &nfit_mem->flags); + } else + dev_dbg(dev, "%s: Force enable labels\n", + dev_name(&adev_dimm->dev)); } populate_shutdown_status(nfit_mem); |