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-rw-r--r--arch/x86/kernel/cpu/amd.c10
-rw-r--r--arch/x86/kernel/cpu/bugs.c92
-rw-r--r--arch/x86/kernel/cpu/common.c38
-rw-r--r--arch/x86/kernel/cpu/resctrl/core.c10
-rw-r--r--arch/x86/kernel/cpu/resctrl/internal.h8
-rw-r--r--arch/x86/kernel/cpu/resctrl/monitor.c48
-rw-r--r--arch/x86/kernel/cpu/resctrl/rdtgroup.c14
7 files changed, 158 insertions, 62 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 2055fb308f..77a1ceb717 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1002,11 +1002,11 @@ static bool cpu_has_zenbleed_microcode(void)
u32 good_rev = 0;
switch (boot_cpu_data.x86_model) {
- case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
- case 0x60 ... 0x67: good_rev = 0x0860010b; break;
- case 0x68 ... 0x6f: good_rev = 0x08608105; break;
- case 0x70 ... 0x7f: good_rev = 0x08701032; break;
- case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
+ case 0x30 ... 0x3f: good_rev = 0x0830107b; break;
+ case 0x60 ... 0x67: good_rev = 0x0860010c; break;
+ case 0x68 ... 0x6f: good_rev = 0x08608107; break;
+ case 0x70 ... 0x7f: good_rev = 0x08701033; break;
+ case 0xa0 ... 0xaf: good_rev = 0x08a00009; break;
default:
return false;
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 48d049cd74..01ac18f561 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -422,6 +422,13 @@ static void __init mmio_select_mitigation(void)
if (boot_cpu_has_bug(X86_BUG_MDS) || (boot_cpu_has_bug(X86_BUG_TAA) &&
boot_cpu_has(X86_FEATURE_RTM)))
setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF);
+
+ /*
+ * X86_FEATURE_CLEAR_CPU_BUF could be enabled by other VERW based
+ * mitigations, disable KVM-only mitigation in that case.
+ */
+ if (boot_cpu_has(X86_FEATURE_CLEAR_CPU_BUF))
+ static_branch_disable(&mmio_stale_data_clear);
else
static_branch_enable(&mmio_stale_data_clear);
@@ -474,6 +481,57 @@ static int __init mmio_stale_data_parse_cmdline(char *str)
early_param("mmio_stale_data", mmio_stale_data_parse_cmdline);
#undef pr_fmt
+#define pr_fmt(fmt) "Register File Data Sampling: " fmt
+
+enum rfds_mitigations {
+ RFDS_MITIGATION_OFF,
+ RFDS_MITIGATION_VERW,
+ RFDS_MITIGATION_UCODE_NEEDED,
+};
+
+/* Default mitigation for Register File Data Sampling */
+static enum rfds_mitigations rfds_mitigation __ro_after_init =
+ IS_ENABLED(CONFIG_MITIGATION_RFDS) ? RFDS_MITIGATION_VERW : RFDS_MITIGATION_OFF;
+
+static const char * const rfds_strings[] = {
+ [RFDS_MITIGATION_OFF] = "Vulnerable",
+ [RFDS_MITIGATION_VERW] = "Mitigation: Clear Register File",
+ [RFDS_MITIGATION_UCODE_NEEDED] = "Vulnerable: No microcode",
+};
+
+static void __init rfds_select_mitigation(void)
+{
+ if (!boot_cpu_has_bug(X86_BUG_RFDS) || cpu_mitigations_off()) {
+ rfds_mitigation = RFDS_MITIGATION_OFF;
+ return;
+ }
+ if (rfds_mitigation == RFDS_MITIGATION_OFF)
+ return;
+
+ if (x86_read_arch_cap_msr() & ARCH_CAP_RFDS_CLEAR)
+ setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF);
+ else
+ rfds_mitigation = RFDS_MITIGATION_UCODE_NEEDED;
+}
+
+static __init int rfds_parse_cmdline(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!boot_cpu_has_bug(X86_BUG_RFDS))
+ return 0;
+
+ if (!strcmp(str, "off"))
+ rfds_mitigation = RFDS_MITIGATION_OFF;
+ else if (!strcmp(str, "on"))
+ rfds_mitigation = RFDS_MITIGATION_VERW;
+
+ return 0;
+}
+early_param("reg_file_data_sampling", rfds_parse_cmdline);
+
+#undef pr_fmt
#define pr_fmt(fmt) "" fmt
static void __init md_clear_update_mitigation(void)
@@ -498,11 +556,19 @@ static void __init md_clear_update_mitigation(void)
taa_mitigation = TAA_MITIGATION_VERW;
taa_select_mitigation();
}
- if (mmio_mitigation == MMIO_MITIGATION_OFF &&
- boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) {
+ /*
+ * MMIO_MITIGATION_OFF is not checked here so that mmio_stale_data_clear
+ * gets updated correctly as per X86_FEATURE_CLEAR_CPU_BUF state.
+ */
+ if (boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) {
mmio_mitigation = MMIO_MITIGATION_VERW;
mmio_select_mitigation();
}
+ if (rfds_mitigation == RFDS_MITIGATION_OFF &&
+ boot_cpu_has_bug(X86_BUG_RFDS)) {
+ rfds_mitigation = RFDS_MITIGATION_VERW;
+ rfds_select_mitigation();
+ }
out:
if (boot_cpu_has_bug(X86_BUG_MDS))
pr_info("MDS: %s\n", mds_strings[mds_mitigation]);
@@ -512,6 +578,8 @@ out:
pr_info("MMIO Stale Data: %s\n", mmio_strings[mmio_mitigation]);
else if (boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN))
pr_info("MMIO Stale Data: Unknown: No mitigations\n");
+ if (boot_cpu_has_bug(X86_BUG_RFDS))
+ pr_info("Register File Data Sampling: %s\n", rfds_strings[rfds_mitigation]);
}
static void __init md_clear_select_mitigation(void)
@@ -519,11 +587,12 @@ static void __init md_clear_select_mitigation(void)
mds_select_mitigation();
taa_select_mitigation();
mmio_select_mitigation();
+ rfds_select_mitigation();
/*
- * As MDS, TAA and MMIO Stale Data mitigations are inter-related, update
- * and print their mitigation after MDS, TAA and MMIO Stale Data
- * mitigation selection is done.
+ * As these mitigations are inter-related and rely on VERW instruction
+ * to clear the microarchitural buffers, update and print their status
+ * after mitigation selection is done for each of these vulnerabilities.
*/
md_clear_update_mitigation();
}
@@ -2612,6 +2681,11 @@ static ssize_t mmio_stale_data_show_state(char *buf)
sched_smt_active() ? "vulnerable" : "disabled");
}
+static ssize_t rfds_show_state(char *buf)
+{
+ return sysfs_emit(buf, "%s\n", rfds_strings[rfds_mitigation]);
+}
+
static char *stibp_state(void)
{
if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
@@ -2771,6 +2845,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
case X86_BUG_GDS:
return gds_show_state(buf);
+ case X86_BUG_RFDS:
+ return rfds_show_state(buf);
+
default:
break;
}
@@ -2845,4 +2922,9 @@ ssize_t cpu_show_gds(struct device *dev, struct device_attribute *attr, char *bu
{
return cpu_show_common(dev, attr, buf, X86_BUG_GDS);
}
+
+ssize_t cpu_show_reg_file_data_sampling(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ return cpu_show_common(dev, attr, buf, X86_BUG_RFDS);
+}
#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 34cac9ea19..97ea52a4e8 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1274,6 +1274,8 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
#define SRSO BIT(5)
/* CPU is affected by GDS */
#define GDS BIT(6)
+/* CPU is affected by Register File Data Sampling */
+#define RFDS BIT(7)
static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS),
@@ -1301,9 +1303,18 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(TIGERLAKE, X86_STEPPING_ANY, GDS),
VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED | GDS),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
+ VULNBL_INTEL_STEPPINGS(ALDERLAKE, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ALDERLAKE_L, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE_P, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE_S, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GRACEMONT, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT_D, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT_PLUS, X86_STEPPING_ANY, RFDS),
VULNBL_AMD(0x15, RETBLEED),
VULNBL_AMD(0x16, RETBLEED),
@@ -1337,6 +1348,24 @@ static bool arch_cap_mmio_immune(u64 ia32_cap)
ia32_cap & ARCH_CAP_SBDR_SSDP_NO);
}
+static bool __init vulnerable_to_rfds(u64 ia32_cap)
+{
+ /* The "immunity" bit trumps everything else: */
+ if (ia32_cap & ARCH_CAP_RFDS_NO)
+ return false;
+
+ /*
+ * VMMs set ARCH_CAP_RFDS_CLEAR for processors not in the blacklist to
+ * indicate that mitigation is needed because guest is running on a
+ * vulnerable hardware or may migrate to such hardware:
+ */
+ if (ia32_cap & ARCH_CAP_RFDS_CLEAR)
+ return true;
+
+ /* Only consult the blacklist when there is no enumeration: */
+ return cpu_matches(cpu_vuln_blacklist, RFDS);
+}
+
static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
{
u64 ia32_cap = x86_read_arch_cap_msr();
@@ -1448,6 +1477,9 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
boot_cpu_has(X86_FEATURE_AVX))
setup_force_cpu_bug(X86_BUG_GDS);
+ if (vulnerable_to_rfds(ia32_cap))
+ setup_force_cpu_bug(X86_BUG_RFDS);
+
if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
return;
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 19e0681f04..d04371e851 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -231,9 +231,7 @@ static bool __get_mem_config_intel(struct rdt_resource *r)
static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
{
struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
- union cpuid_0x10_3_eax eax;
- union cpuid_0x10_x_edx edx;
- u32 ebx, ecx, subleaf;
+ u32 eax, ebx, ecx, edx, subleaf;
/*
* Query CPUID_Fn80000020_EDX_x01 for MBA and
@@ -241,9 +239,9 @@ static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
*/
subleaf = (r->rid == RDT_RESOURCE_SMBA) ? 2 : 1;
- cpuid_count(0x80000020, subleaf, &eax.full, &ebx, &ecx, &edx.full);
- hw_res->num_closid = edx.split.cos_max + 1;
- r->default_ctrl = MAX_MBA_BW_AMD;
+ cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
+ hw_res->num_closid = edx + 1;
+ r->default_ctrl = 1 << eax;
/* AMD does not use delay */
r->membw.delay_linear = false;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index a4f1aa15f0..52e7e7deee 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -18,7 +18,6 @@
#define MBM_OVERFLOW_INTERVAL 1000
#define MAX_MBA_BW 100u
#define MBA_IS_LINEAR 0x4
-#define MAX_MBA_BW_AMD 0x800
#define MBM_CNTR_WIDTH_OFFSET_AMD 20
#define RMID_VAL_ERROR BIT_ULL(63)
@@ -296,14 +295,10 @@ struct rftype {
* struct mbm_state - status for each MBM counter in each domain
* @prev_bw_bytes: Previous bytes value read for bandwidth calculation
* @prev_bw: The most recent bandwidth in MBps
- * @delta_bw: Difference between the current and previous bandwidth
- * @delta_comp: Indicates whether to compute the delta_bw
*/
struct mbm_state {
u64 prev_bw_bytes;
u32 prev_bw;
- u32 delta_bw;
- bool delta_comp;
};
/**
@@ -395,6 +390,8 @@ struct rdt_parse_data {
* @msr_update: Function pointer to update QOS MSRs
* @mon_scale: cqm counter * mon_scale = occupancy in bytes
* @mbm_width: Monitor width, to detect and correct for overflow.
+ * @mbm_cfg_mask: Bandwidth sources that can be tracked when Bandwidth
+ * Monitoring Event Configuration (BMEC) is supported.
* @cdp_enabled: CDP state of this resource
*
* Members of this structure are either private to the architecture
@@ -409,6 +406,7 @@ struct rdt_hw_resource {
struct rdt_resource *r);
unsigned int mon_scale;
unsigned int mbm_width;
+ unsigned int mbm_cfg_mask;
bool cdp_enabled;
};
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index f136ac0468..3a6c069614 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -440,9 +440,6 @@ static void mbm_bw_count(u32 rmid, struct rmid_read *rr)
cur_bw = bytes / SZ_1M;
- if (m->delta_comp)
- m->delta_bw = abs(cur_bw - m->prev_bw);
- m->delta_comp = false;
m->prev_bw = cur_bw;
}
@@ -520,11 +517,11 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
{
u32 closid, rmid, cur_msr_val, new_msr_val;
struct mbm_state *pmbm_data, *cmbm_data;
- u32 cur_bw, delta_bw, user_bw;
struct rdt_resource *r_mba;
struct rdt_domain *dom_mba;
struct list_head *head;
struct rdtgroup *entry;
+ u32 cur_bw, user_bw;
if (!is_mbm_local_enabled())
return;
@@ -543,7 +540,6 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
cur_bw = pmbm_data->prev_bw;
user_bw = dom_mba->mbps_val[closid];
- delta_bw = pmbm_data->delta_bw;
/* MBA resource doesn't support CDP */
cur_msr_val = resctrl_arch_get_config(r_mba, dom_mba, closid, CDP_NONE);
@@ -555,49 +551,31 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm)
list_for_each_entry(entry, head, mon.crdtgrp_list) {
cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
cur_bw += cmbm_data->prev_bw;
- delta_bw += cmbm_data->delta_bw;
}
/*
* Scale up/down the bandwidth linearly for the ctrl group. The
* bandwidth step is the bandwidth granularity specified by the
* hardware.
- *
- * The delta_bw is used when increasing the bandwidth so that we
- * dont alternately increase and decrease the control values
- * continuously.
- *
- * For ex: consider cur_bw = 90MBps, user_bw = 100MBps and if
- * bandwidth step is 20MBps(> user_bw - cur_bw), we would keep
- * switching between 90 and 110 continuously if we only check
- * cur_bw < user_bw.
+ * Always increase throttling if current bandwidth is above the
+ * target set by user.
+ * But avoid thrashing up and down on every poll by checking
+ * whether a decrease in throttling is likely to push the group
+ * back over target. E.g. if currently throttling to 30% of bandwidth
+ * on a system with 10% granularity steps, check whether moving to
+ * 40% would go past the limit by multiplying current bandwidth by
+ * "(30 + 10) / 30".
*/
if (cur_msr_val > r_mba->membw.min_bw && user_bw < cur_bw) {
new_msr_val = cur_msr_val - r_mba->membw.bw_gran;
} else if (cur_msr_val < MAX_MBA_BW &&
- (user_bw > (cur_bw + delta_bw))) {
+ (user_bw > (cur_bw * (cur_msr_val + r_mba->membw.min_bw) / cur_msr_val))) {
new_msr_val = cur_msr_val + r_mba->membw.bw_gran;
} else {
return;
}
resctrl_arch_update_one(r_mba, dom_mba, closid, CDP_NONE, new_msr_val);
-
- /*
- * Delta values are updated dynamically package wise for each
- * rdtgrp every time the throttle MSR changes value.
- *
- * This is because (1)the increase in bandwidth is not perfectly
- * linear and only "approximately" linear even when the hardware
- * says it is linear.(2)Also since MBA is a core specific
- * mechanism, the delta values vary based on number of cores used
- * by the rdtgrp.
- */
- pmbm_data->delta_comp = true;
- list_for_each_entry(entry, head, mon.crdtgrp_list) {
- cmbm_data = &dom_mbm->mbm_local[entry->mon.rmid];
- cmbm_data->delta_comp = true;
- }
}
static void mbm_update(struct rdt_resource *r, struct rdt_domain *d, int rmid)
@@ -813,6 +791,12 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
return ret;
if (rdt_cpu_has(X86_FEATURE_BMEC)) {
+ u32 eax, ebx, ecx, edx;
+
+ /* Detect list of bandwidth sources that can be tracked */
+ cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
+ hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
+
if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
mbm_total_event.configurable = true;
mbm_config_rftype_init("mbm_total_bytes_config");
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 69a1de9238..2b69e560b0 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1620,12 +1620,6 @@ static int mbm_config_write_domain(struct rdt_resource *r,
struct mon_config_info mon_info = {0};
int ret = 0;
- /* mon_config cannot be more than the supported set of events */
- if (val > MAX_EVT_CONFIG_BITS) {
- rdt_last_cmd_puts("Invalid event configuration\n");
- return -EINVAL;
- }
-
/*
* Read the current config value first. If both are the same then
* no need to write it again.
@@ -1663,6 +1657,7 @@ out:
static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
{
+ struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
char *dom_str = NULL, *id_str;
unsigned long dom_id, val;
struct rdt_domain *d;
@@ -1686,6 +1681,13 @@ next:
return -EINVAL;
}
+ /* Value from user cannot be more than the supported set of events */
+ if ((val & hw_res->mbm_cfg_mask) != val) {
+ rdt_last_cmd_printf("Invalid event configuration: max valid mask is 0x%02x\n",
+ hw_res->mbm_cfg_mask);
+ return -EINVAL;
+ }
+
list_for_each_entry(d, &r->domains, list) {
if (d->id == dom_id) {
ret = mbm_config_write_domain(r, d, evtid, val);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-30 16:32:29 +0000