Merge tag 'gds-for-linus-2023-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86/gds fixes from Dave Hansen:
 "Mitigate Gather Data Sampling issue:

   - Add Base GDS mitigation

   - Support GDS_NO under KVM

   - Fix a documentation typo"

* tag 'gds-for-linus-2023-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/x86: Fix backwards on/off logic about YMM support
  KVM: Add GDS_NO support to KVM
  x86/speculation: Add Kconfig option for GDS
  x86/speculation: Add force option to GDS mitigation
  x86/speculation: Add Gather Data Sampling mitigation

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index f111586d1cce..52df435eecf8 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -583,6 +583,12 @@ ssize_t __weak cpu_show_spec_rstack_overflow(struct device *dev,
 	return sysfs_emit(buf, "Not affected\n");
 }
 
+ssize_t __weak cpu_show_gds(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "Not affected\n");
+}
+
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
 static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
 static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
@@ -595,6 +601,7 @@ static DEVICE_ATTR(srbds, 0444, cpu_show_srbds, NULL);
 static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL);
 static DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL);
 static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NULL);
+static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL);
 
 static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_meltdown.attr,
@@ -609,6 +616,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_mmio_stale_data.attr,
 	&dev_attr_retbleed.attr,
 	&dev_attr_spec_rstack_overflow.attr,
+	&dev_attr_gather_data_sampling.attr,
 	NULL
 };