summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/powerpc/include/asm/book3s/64/kup-radix.h66
-rw-r--r--arch/powerpc/include/asm/exception-64s.h12
-rw-r--r--arch/powerpc/include/asm/feature-fixups.h19
-rw-r--r--arch/powerpc/include/asm/kup.h26
-rw-r--r--arch/powerpc/include/asm/security_features.h7
-rw-r--r--arch/powerpc/include/asm/setup.h4
-rw-r--r--arch/powerpc/kernel/exceptions-64s.S80
-rw-r--r--arch/powerpc/kernel/setup_64.c122
-rw-r--r--arch/powerpc/kernel/syscall_64.c2
-rw-r--r--arch/powerpc/kernel/vmlinux.lds.S14
-rw-r--r--arch/powerpc/lib/feature-fixups.c104
-rw-r--r--arch/powerpc/platforms/powernv/setup.c24
-rw-r--r--arch/powerpc/platforms/pseries/mobility.c4
-rw-r--r--arch/powerpc/platforms/pseries/pseries.h2
-rw-r--r--arch/powerpc/platforms/pseries/setup.c15
15 files changed, 421 insertions, 80 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/kup-radix.h b/arch/powerpc/include/asm/book3s/64/kup-radix.h
index 3ee1ec60be84..28716e2f13e3 100644
--- a/arch/powerpc/include/asm/book3s/64/kup-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/kup-radix.h
@@ -27,6 +27,7 @@
#endif
.endm
+#ifdef CONFIG_PPC_KUAP
.macro kuap_check_amr gpr1, gpr2
#ifdef CONFIG_PPC_KUAP_DEBUG
BEGIN_MMU_FTR_SECTION_NESTED(67)
@@ -38,6 +39,7 @@
END_MMU_FTR_SECTION_NESTED_IFSET(MMU_FTR_RADIX_KUAP, 67)
#endif
.endm
+#endif
.macro kuap_save_amr_and_lock gpr1, gpr2, use_cr, msr_pr_cr
#ifdef CONFIG_PPC_KUAP
@@ -61,6 +63,8 @@
#else /* !__ASSEMBLY__ */
+DECLARE_STATIC_KEY_FALSE(uaccess_flush_key);
+
#ifdef CONFIG_PPC_KUAP
#include <asm/mmu.h>
@@ -103,8 +107,16 @@ static inline void kuap_check_amr(void)
static inline unsigned long get_kuap(void)
{
+ /*
+ * We return AMR_KUAP_BLOCKED when we don't support KUAP because
+ * prevent_user_access_return needs to return AMR_KUAP_BLOCKED to
+ * cause restore_user_access to do a flush.
+ *
+ * This has no effect in terms of actually blocking things on hash,
+ * so it doesn't break anything.
+ */
if (!early_mmu_has_feature(MMU_FTR_RADIX_KUAP))
- return 0;
+ return AMR_KUAP_BLOCKED;
return mfspr(SPRN_AMR);
}
@@ -123,6 +135,29 @@ static inline void set_kuap(unsigned long value)
isync();
}
+static inline bool
+bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
+{
+ return WARN(mmu_has_feature(MMU_FTR_RADIX_KUAP) &&
+ (regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE : AMR_KUAP_BLOCK_READ)),
+ "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
+}
+#else /* CONFIG_PPC_KUAP */
+static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr) { }
+
+static inline unsigned long kuap_get_and_check_amr(void)
+{
+ return 0UL;
+}
+
+static inline unsigned long get_kuap(void)
+{
+ return AMR_KUAP_BLOCKED;
+}
+
+static inline void set_kuap(unsigned long value) { }
+#endif /* !CONFIG_PPC_KUAP */
+
static __always_inline void allow_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir)
{
@@ -142,6 +177,8 @@ static inline void prevent_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir)
{
set_kuap(AMR_KUAP_BLOCKED);
+ if (static_branch_unlikely(&uaccess_flush_key))
+ do_uaccess_flush();
}
static inline unsigned long prevent_user_access_return(void)
@@ -149,6 +186,8 @@ static inline unsigned long prevent_user_access_return(void)
unsigned long flags = get_kuap();
set_kuap(AMR_KUAP_BLOCKED);
+ if (static_branch_unlikely(&uaccess_flush_key))
+ do_uaccess_flush();
return flags;
}
@@ -156,30 +195,9 @@ static inline unsigned long prevent_user_access_return(void)
static inline void restore_user_access(unsigned long flags)
{
set_kuap(flags);
+ if (static_branch_unlikely(&uaccess_flush_key) && flags == AMR_KUAP_BLOCKED)
+ do_uaccess_flush();
}
-
-static inline bool
-bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
-{
- return WARN(mmu_has_feature(MMU_FTR_RADIX_KUAP) &&
- (regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE : AMR_KUAP_BLOCK_READ)),
- "Bug: %s fault blocked by AMR!", is_write ? "Write" : "Read");
-}
-#else /* CONFIG_PPC_KUAP */
-static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr)
-{
-}
-
-static inline void kuap_check_amr(void)
-{
-}
-
-static inline unsigned long kuap_get_and_check_amr(void)
-{
- return 0;
-}
-#endif /* CONFIG_PPC_KUAP */
-
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_BOOK3S_64_KUP_RADIX_H */
diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
index ebe95aa04d53..1d32b174ab6a 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -57,11 +57,18 @@
nop; \
nop
+#define ENTRY_FLUSH_SLOT \
+ ENTRY_FLUSH_FIXUP_SECTION; \
+ nop; \
+ nop; \
+ nop;
+
/*
* r10 must be free to use, r13 must be paca
*/
#define INTERRUPT_TO_KERNEL \
- STF_ENTRY_BARRIER_SLOT
+ STF_ENTRY_BARRIER_SLOT; \
+ ENTRY_FLUSH_SLOT
/*
* Macros for annotating the expected destination of (h)rfid
@@ -137,6 +144,9 @@
RFSCV; \
b rfscv_flush_fallback
+#else /* __ASSEMBLY__ */
+/* Prototype for function defined in exceptions-64s.S */
+void do_uaccess_flush(void);
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_EXCEPTION_H */
diff --git a/arch/powerpc/include/asm/feature-fixups.h b/arch/powerpc/include/asm/feature-fixups.h
index b0af97add751..fbd406cd6916 100644
--- a/arch/powerpc/include/asm/feature-fixups.h
+++ b/arch/powerpc/include/asm/feature-fixups.h
@@ -205,6 +205,22 @@ label##3: \
FTR_ENTRY_OFFSET 955b-956b; \
.popsection;
+#define UACCESS_FLUSH_FIXUP_SECTION \
+959: \
+ .pushsection __uaccess_flush_fixup,"a"; \
+ .align 2; \
+960: \
+ FTR_ENTRY_OFFSET 959b-960b; \
+ .popsection;
+
+#define ENTRY_FLUSH_FIXUP_SECTION \
+957: \
+ .pushsection __entry_flush_fixup,"a"; \
+ .align 2; \
+958: \
+ FTR_ENTRY_OFFSET 957b-958b; \
+ .popsection;
+
#define RFI_FLUSH_FIXUP_SECTION \
951: \
.pushsection __rfi_flush_fixup,"a"; \
@@ -237,8 +253,11 @@ label##3: \
#include <linux/types.h>
extern long stf_barrier_fallback;
+extern long entry_flush_fallback;
extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
+extern long __start___uaccess_flush_fixup, __stop___uaccess_flush_fixup;
+extern long __start___entry_flush_fixup, __stop___entry_flush_fixup;
extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
extern long __start___barrier_nospec_fixup, __stop___barrier_nospec_fixup;
extern long __start__btb_flush_fixup, __stop__btb_flush_fixup;
diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h
index 1d0f7d838b2e..0d93331d0fab 100644
--- a/arch/powerpc/include/asm/kup.h
+++ b/arch/powerpc/include/asm/kup.h
@@ -14,7 +14,7 @@
#define KUAP_CURRENT_WRITE 8
#define KUAP_CURRENT (KUAP_CURRENT_READ | KUAP_CURRENT_WRITE)
-#ifdef CONFIG_PPC64
+#ifdef CONFIG_PPC_BOOK3S_64
#include <asm/book3s/64/kup-radix.h>
#endif
#ifdef CONFIG_PPC_8xx
@@ -35,6 +35,9 @@
.macro kuap_check current, gpr
.endm
+.macro kuap_check_amr gpr1, gpr2
+.endm
+
#endif
#else /* !__ASSEMBLY__ */
@@ -53,17 +56,28 @@ static inline void setup_kuep(bool disabled) { }
void setup_kuap(bool disabled);
#else
static inline void setup_kuap(bool disabled) { }
+
+static inline bool
+bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
+{
+ return false;
+}
+
+static inline void kuap_check_amr(void) { }
+
+/*
+ * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush
+ * the L1D cache after user accesses. Only include the empty stubs for other
+ * platforms.
+ */
+#ifndef CONFIG_PPC_BOOK3S_64
static inline void allow_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir) { }
static inline void prevent_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir) { }
static inline unsigned long prevent_user_access_return(void) { return 0UL; }
static inline void restore_user_access(unsigned long flags) { }
-static inline bool
-bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
-{
- return false;
-}
+#endif /* CONFIG_PPC_BOOK3S_64 */
#endif /* CONFIG_PPC_KUAP */
static inline void allow_read_from_user(const void __user *from, unsigned long size)
diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index fbb8fa32150f..b774a4477d5f 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -86,12 +86,19 @@ static inline bool security_ftr_enabled(u64 feature)
// Software required to flush link stack on context switch
#define SEC_FTR_FLUSH_LINK_STACK 0x0000000000001000ull
+// The L1-D cache should be flushed when entering the kernel
+#define SEC_FTR_L1D_FLUSH_ENTRY 0x0000000000004000ull
+
+// The L1-D cache should be flushed after user accesses from the kernel
+#define SEC_FTR_L1D_FLUSH_UACCESS 0x0000000000008000ull
// Features enabled by default
#define SEC_FTR_DEFAULT \
(SEC_FTR_L1D_FLUSH_HV | \
SEC_FTR_L1D_FLUSH_PR | \
SEC_FTR_BNDS_CHK_SPEC_BAR | \
+ SEC_FTR_L1D_FLUSH_ENTRY | \
+ SEC_FTR_L1D_FLUSH_UACCESS | \
SEC_FTR_FAVOUR_SECURITY)
#endif /* _ASM_POWERPC_SECURITY_FEATURES_H */
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 9efbddee2bca..a466749703f1 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -52,12 +52,16 @@ enum l1d_flush_type {
};
void setup_rfi_flush(enum l1d_flush_type, bool enable);
+void setup_entry_flush(bool enable);
+void setup_uaccess_flush(bool enable);
void do_rfi_flush_fixups(enum l1d_flush_type types);
#ifdef CONFIG_PPC_BARRIER_NOSPEC
void setup_barrier_nospec(void);
#else
static inline void setup_barrier_nospec(void) { };
#endif
+void do_uaccess_flush_fixups(enum l1d_flush_type types);
+void do_entry_flush_fixups(enum l1d_flush_type types);
void do_barrier_nospec_fixups(bool enable);
extern bool barrier_nospec_enabled;
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index f7d748b88705..f63a3d3bca3d 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -2951,15 +2951,8 @@ TRAMP_REAL_BEGIN(stf_barrier_fallback)
.endr
blr
-TRAMP_REAL_BEGIN(rfi_flush_fallback)
- SET_SCRATCH0(r13);
- GET_PACA(r13);
- std r1,PACA_EXRFI+EX_R12(r13)
- ld r1,PACAKSAVE(r13)
- std r9,PACA_EXRFI+EX_R9(r13)
- std r10,PACA_EXRFI+EX_R10(r13)
- std r11,PACA_EXRFI+EX_R11(r13)
- mfctr r9
+/* Clobbers r10, r11, ctr */
+.macro L1D_DISPLACEMENT_FLUSH
ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
ld r11,PACA_L1D_FLUSH_SIZE(r13)
srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
@@ -2970,7 +2963,7 @@ TRAMP_REAL_BEGIN(rfi_flush_fallback)
sync
/*
- * The load adresses are at staggered offsets within cachelines,
+ * The load addresses are at staggered offsets within cachelines,
* which suits some pipelines better (on others it should not
* hurt).
*/
@@ -2985,7 +2978,30 @@ TRAMP_REAL_BEGIN(rfi_flush_fallback)
ld r11,(0x80 + 8)*7(r10)
addi r10,r10,0x80*8
bdnz 1b
+.endm
+
+TRAMP_REAL_BEGIN(entry_flush_fallback)
+ std r9,PACA_EXRFI+EX_R9(r13)
+ std r10,PACA_EXRFI+EX_R10(r13)
+ std r11,PACA_EXRFI+EX_R11(r13)
+ mfctr r9
+ L1D_DISPLACEMENT_FLUSH
+ mtctr r9
+ ld r9,PACA_EXRFI+EX_R9(r13)
+ ld r10,PACA_EXRFI+EX_R10(r13)
+ ld r11,PACA_EXRFI+EX_R11(r13)
+ blr
+TRAMP_REAL_BEGIN(rfi_flush_fallback)
+ SET_SCRATCH0(r13);
+ GET_PACA(r13);
+ std r1,PACA_EXRFI+EX_R12(r13)
+ ld r1,PACAKSAVE(r13)
+ std r9,PACA_EXRFI+EX_R9(r13)
+ std r10,PACA_EXRFI+EX_R10(r13)
+ std r11,PACA_EXRFI+EX_R11(r13)
+ mfctr r9
+ L1D_DISPLACEMENT_FLUSH
mtctr r9
ld r9,PACA_EXRFI+EX_R9(r13)
ld r10,PACA_EXRFI+EX_R10(r13)
@@ -3003,32 +3019,7 @@ TRAMP_REAL_BEGIN(hrfi_flush_fallback)
std r10,PACA_EXRFI+EX_R10(r13)
std r11,PACA_EXRFI+EX_R11(r13)
mfctr r9
- ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
- ld r11,PACA_L1D_FLUSH_SIZE(r13)
- srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
- mtctr r11
- DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */
-
- /* order ld/st prior to dcbt stop all streams with flushing */
- sync
-
- /*
- * The load adresses are at staggered offsets within cachelines,
- * which suits some pipelines better (on others it should not
- * hurt).
- */
-1:
- ld r11,(0x80 + 8)*0(r10)
- ld r11,(0x80 + 8)*1(r10)
- ld r11,(0x80 + 8)*2(r10)
- ld r11,(0x80 + 8)*3(r10)
- ld r11,(0x80 + 8)*4(r10)
- ld r11,(0x80 + 8)*5(r10)
- ld r11,(0x80 + 8)*6(r10)
- ld r11,(0x80 + 8)*7(r10)
- addi r10,r10,0x80*8
- bdnz 1b
-
+ L1D_DISPLACEMENT_FLUSH
mtctr r9
ld r9,PACA_EXRFI+EX_R9(r13)
ld r10,PACA_EXRFI+EX_R10(r13)
@@ -3079,8 +3070,21 @@ TRAMP_REAL_BEGIN(rfscv_flush_fallback)
RFSCV
USE_TEXT_SECTION()
- MASKED_INTERRUPT
- MASKED_INTERRUPT hsrr=1
+
+_GLOBAL(do_uaccess_flush)
+ UACCESS_FLUSH_FIXUP_SECTION
+ nop
+ nop
+ nop
+ blr
+ L1D_DISPLACEMENT_FLUSH
+ blr
+_ASM_NOKPROBE_SYMBOL(do_uaccess_flush)
+EXPORT_SYMBOL(do_uaccess_flush)
+
+
+MASKED_INTERRUPT
+MASKED_INTERRUPT hsrr=1
#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
kvmppc_skip_interrupt:
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index bb9cab3641d7..74fd47f46fa5 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -945,7 +945,13 @@ early_initcall(disable_hardlockup_detector);
static enum l1d_flush_type enabled_flush_types;
static void *l1d_flush_fallback_area;
static bool no_rfi_flush;
+static bool no_entry_flush;
+static bool no_uaccess_flush;
bool rfi_flush;
+bool entry_flush;
+bool uaccess_flush;
+DEFINE_STATIC_KEY_FALSE(uaccess_flush_key);
+EXPORT_SYMBOL(uaccess_flush_key);
static int __init handle_no_rfi_flush(char *p)
{
@@ -955,6 +961,22 @@ static int __init handle_no_rfi_flush(char *p)
}
early_param("no_rfi_flush", handle_no_rfi_flush);
+static int __init handle_no_entry_flush(char *p)
+{
+ pr_info("entry-flush: disabled on command line.");
+ no_entry_flush = true;
+ return 0;
+}
+early_param("no_entry_flush", handle_no_entry_flush);
+
+static int __init handle_no_uaccess_flush(char *p)
+{
+ pr_info("uaccess-flush: disabled on command line.");
+ no_uaccess_flush = true;
+ return 0;
+}
+early_param("no_uaccess_flush", handle_no_uaccess_flush);
+
/*
* The RFI flush is not KPTI, but because users will see doco that says to use
* nopti we hijack that option here to also disable the RFI flush.
@@ -986,6 +1008,32 @@ void rfi_flush_enable(bool enable)
rfi_flush = enable;
}
+void entry_flush_enable(bool enable)
+{
+ if (enable) {
+ do_entry_flush_fixups(enabled_flush_types);
+ on_each_cpu(do_nothing, NULL, 1);
+ } else {
+ do_entry_flush_fixups(L1D_FLUSH_NONE);
+ }
+
+ entry_flush = enable;
+}
+
+void uaccess_flush_enable(bool enable)
+{
+ if (enable) {
+ do_uaccess_flush_fixups(enabled_flush_types);
+ static_branch_enable(&uaccess_flush_key);
+ on_each_cpu(do_nothing, NULL, 1);
+ } else {
+ static_branch_disable(&uaccess_flush_key);
+ do_uaccess_flush_fixups(L1D_FLUSH_NONE);
+ }
+
+ uaccess_flush = enable;
+}
+
static void __ref init_fallback_flush(void)
{
u64 l1d_size, limit;
@@ -1044,10 +1092,28 @@ void setup_rfi_flush(enum l1d_flush_type types, bool enable)
enabled_flush_types = types;
- if (!no_rfi_flush && !cpu_mitigations_off())
+ if (!cpu_mitigations_off() && !no_rfi_flush)
rfi_flush_enable(enable);
}
+void setup_entry_flush(bool enable)
+{
+ if (cpu_mitigations_off())
+ return;
+
+ if (!no_entry_flush)
+ entry_flush_enable(enable);
+}
+
+void setup_uaccess_flush(bool enable)
+{
+ if (cpu_mitigations_off())
+ return;
+
+ if (!no_uaccess_flush)
+ uaccess_flush_enable(enable);
+}
+
#ifdef CONFIG_DEBUG_FS
static int rfi_flush_set(void *data, u64 val)
{
@@ -1075,9 +1141,63 @@ static int rfi_flush_get(void *data, u64 *val)
DEFINE_SIMPLE_ATTRIBUTE(fops_rfi_flush, rfi_flush_get, rfi_flush_set, "%llu\n");
+static int entry_flush_set(void *data, u64 val)
+{
+ bool enable;
+
+ if (val == 1)
+ enable = true;
+ else if (val == 0)
+ enable = false;
+ else
+ return -EINVAL;
+
+ /* Only do anything if we're changing state */
+ if (enable != entry_flush)
+ entry_flush_enable(enable);
+
+ return 0;
+}
+
+static int entry_flush_get(void *data, u64 *val)
+{
+ *val = entry_flush ? 1 : 0;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_entry_flush, entry_flush_get, entry_flush_set, "%llu\n");
+
+static int uaccess_flush_set(void *data, u64 val)
+{
+ bool enable;
+
+ if (val == 1)
+ enable = true;
+ else if (val == 0)
+ enable = false;
+ else
+ return -EINVAL;
+
+ /* Only do anything if we're changing state */
+ if (enable != uaccess_flush)
+ uaccess_flush_enable(enable);
+
+ return 0;
+}
+
+static int uaccess_flush_get(void *data, u64 *val)
+{
+ *val = uaccess_flush ? 1 : 0;
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_uaccess_flush, uaccess_flush_get, uaccess_flush_set, "%llu\n");
+
static __init int rfi_flush_debugfs_init(void)
{
debugfs_create_file("rfi_flush", 0600, powerpc_debugfs_root, NULL, &fops_rfi_flush);
+ debugfs_create_file("entry_flush", 0600, powerpc_debugfs_root, NULL, &fops_entry_flush);
+ debugfs_create_file("uaccess_flush", 0600, powerpc_debugfs_root, NULL, &fops_uaccess_flush);
return 0;
}
device_initcall(rfi_flush_debugfs_init);
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
index 8e50818aa50b..310bcd768cd5 100644
--- a/arch/powerpc/kernel/syscall_64.c
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -2,7 +2,7 @@
#include <linux/err.h>
#include <asm/asm-prototypes.h>
-#include <asm/book3s/64/kup-radix.h>
+#include <asm/kup.h>
#include <asm/cputime.h>
#include <asm/hw_irq.h>
#include <asm/kprobes.h>
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index e0548b4950de..6db90cdf11da 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -132,6 +132,20 @@ SECTIONS
}
. = ALIGN(8);
+ __uaccess_flush_fixup : AT(ADDR(__uaccess_flush_fixup) - LOAD_OFFSET) {
+ __start___uaccess_flush_fixup = .;
+ *(__uaccess_flush_fixup)
+ __stop___uaccess_flush_fixup = .;
+ }
+
+ . = ALIGN(8);
+ __entry_flush_fixup : AT(ADDR(__entry_flush_fixup) - LOAD_OFFSET) {
+ __start___entry_flush_fixup = .;
+ *(__entry_flush_fixup)
+ __stop___entry_flush_fixup = .;
+ }
+
+ . = ALIGN(8);
__stf_exit_barrier_fixup : AT(ADDR(__stf_exit_barrier_fixup) - LOAD_OFFSET) {
__start___stf_exit_barrier_fixup = .;
*(__stf_exit_barrier_fixup)
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 4c0a7ee9fa00..321c12a9ef6b 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -234,6 +234,110 @@ void do_stf_barrier_fixups(enum stf_barrier_type types)
do_stf_exit_barrier_fixups(types);
}
+void do_uaccess_flush_fixups(enum l1d_flush_type types)
+{
+ unsigned int instrs[4], *dest;
+ long *start, *end;
+ int i;
+
+ start = PTRRELOC(&__start___uaccess_flush_fixup);
+ end = PTRRELOC(&__stop___uaccess_flush_fixup);
+
+ instrs[0] = 0x60000000; /* nop */
+ instrs[1] = 0x60000000; /* nop */
+ instrs[2] = 0x60000000; /* nop */
+ instrs[3] = 0x4e800020; /* blr */
+
+ i = 0;
+ if (types == L1D_FLUSH_FALLBACK) {
+ instrs[3] = 0x60000000; /* nop */
+ /* fallthrough to fallback flush */
+ }
+
+ if (types & L1D_FLUSH_ORI) {
+ instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+ instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
+ }
+
+ if (types & L1D_FLUSH_MTTRIG)
+ instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
+
+ for (i = 0; start < end; start++, i++) {
+ dest = (void *)start + *start;
+
+ pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+ patch_instruction((struct ppc_inst *)dest, ppc_inst(instrs[0]));
+
+ patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
+ patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
+ patch_instruction((struct ppc_inst *)(dest + 3), ppc_inst(instrs[3]));
+ }
+
+ printk(KERN_DEBUG "uaccess-flush: patched %d locations (%s flush)\n", i,
+ (types == L1D_FLUSH_NONE) ? "no" :
+ (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
+ (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
+ ? "ori+mttrig type"
+ : "ori type" :
+ (types & L1D_FLUSH_MTTRIG) ? "mttrig type"
+ : "unknown");
+}
+
+void do_entry_flush_fixups(enum l1d_flush_type types)
+{
+ unsigned int instrs[3], *dest;
+ long *start, *end;
+ int i;
+
+ start = PTRRELOC(&__start___entry_flush_fixup);
+ end = PTRRELOC(&__stop___entry_flush_fixup);
+
+ instrs[0] = 0x60000000; /* nop */
+ instrs[1] = 0x60000000; /* nop */
+ instrs[2] = 0x60000000; /* nop */
+
+ i = 0;
+ if (types == L1D_FLUSH_FALLBACK) {
+ instrs[i++] = 0x7d4802a6; /* mflr r10 */
+ instrs[i++] = 0x60000000; /* branch patched below */
+ instrs[i++] = 0x7d4803a6; /* mtlr r10 */
+ }
+
+ if (types & L1D_FLUSH_ORI) {
+ instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+ instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
+ }
+
+ if (types & L1D_FLUSH_MTTRIG)
+ instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
+
+ for (i = 0; start < end; start++, i++) {
+ dest = (void *)start + *start;
+
+ pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+ patch_instruction((struct ppc_inst *)dest, ppc_inst(instrs[0]));
+
+ if (types == L1D_FLUSH_FALLBACK)
+ patch_branch((struct ppc_inst *)(dest + 1), (unsigned long)&entry_flush_fallback,
+ BRANCH_SET_LINK);
+ else
+ patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
+
+ patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
+ }
+
+ printk(KERN_DEBUG "entry-flush: patched %d locations (%s flush)\n", i,
+ (types == L1D_FLUSH_NONE) ? "no" :
+ (types == L1D_FLUSH_FALLBACK) ? "fallback displacement" :
+ (types & L1D_FLUSH_ORI) ? (types & L1D_FLUSH_MTTRIG)
+ ? "ori+mttrig type"
+ : "ori type" :
+ (types & L1D_FLUSH_MTTRIG) ? "mttrig type"
+ : "unknown");
+}
+
void do_rfi_flush_fixups(enum l1d_flush_type types)
{
unsigned int instrs[3], *dest;
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 9acaa0f131b9..46115231a3b2 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -98,7 +98,7 @@ static void init_fw_feat_flags(struct device_node *np)
security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
}
-static void pnv_setup_rfi_flush(void)
+static void pnv_setup_security_mitigations(void)
{
struct device_node *np, *fw_features;
enum l1d_flush_type type;
@@ -122,12 +122,31 @@ static void pnv_setup_rfi_flush(void)
type = L1D_FLUSH_ORI;
}
+ /*
+ * If we are non-Power9 bare metal, we don't need to flush on kernel
+ * entry or after user access: they fix a P9 specific vulnerability.
+ */
+ if (!pvr_version_is(PVR_POWER9)) {
+ security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
+ security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
+ }
+
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
(security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || \
security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
setup_rfi_flush(type, enable);
setup_count_cache_flush();
+
+ enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+ security_ftr_enabled(SEC_FTR_L1D_FLUSH_ENTRY);
+ setup_entry_flush(enable);
+
+ enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+ security_ftr_enabled(SEC_FTR_L1D_FLUSH_UACCESS);
+ setup_uaccess_flush(enable);
+
+ setup_stf_barrier();
}
static void __init pnv_check_guarded_cores(void)
@@ -156,8 +175,7 @@ static void __init pnv_setup_arch(void)
{
set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
- pnv_setup_rfi_flush();
- setup_stf_barrier();
+ pnv_setup_security_mitigations();
/* Initialize SMP */
pnv_smp_init();
diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index d6f4162478a5..2f73cb5bf12d 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -349,8 +349,8 @@ void post_mobility_fixup(void)
cpus_read_unlock();
- /* Possibly switch to a new RFI flush type */
- pseries_setup_rfi_flush();
+ /* Possibly switch to a new L1 flush type */
+ pseries_setup_security_mitigations();
/* Reinitialise system information for hv-24x7 */
read_24x7_sys_info();
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index 13fa370a87e4..593840847cd3 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -111,7 +111,7 @@ static inline unsigned long cmo_get_page_size(void)
int dlpar_workqueue_init(void);
-void pseries_setup_rfi_flush(void);
+void pseries_setup_security_mitigations(void);
void pseries_lpar_read_hblkrm_characteristics(void);
#endif /* _PSERIES_PSERIES_H */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 633c45ec406d..090c13f6c881 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -542,7 +542,7 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
}
-void pseries_setup_rfi_flush(void)
+void pseries_setup_security_mitigations(void)
{
struct h_cpu_char_result result;
enum l1d_flush_type types;
@@ -579,6 +579,16 @@ void pseries_setup_rfi_flush(void)
setup_rfi_flush(types, enable);
setup_count_cache_flush();
+
+ enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+ security_ftr_enabled(SEC_FTR_L1D_FLUSH_ENTRY);
+ setup_entry_flush(enable);
+
+ enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+ security_ftr_enabled(SEC_FTR_L1D_FLUSH_UACCESS);
+ setup_uaccess_flush(enable);
+
+ setup_stf_barrier();
}
#ifdef CONFIG_PCI_IOV
@@ -768,8 +778,7 @@ static void __init pSeries_setup_arch(void)
fwnmi_init();
- pseries_setup_rfi_flush();
- setup_stf_barrier();
+ pseries_setup_security_mitigations();
pseries_lpar_read_hblkrm_characteristics();
/* By default, only probe PCI (can be overridden by rtas_pci) */