Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
- further Spectre variant 1 fixes for user accessors.
- kbuild cleanups (Masahiro Yamada)
- hook up sync core functionality (Will Deacon)
- nommu updates for hypervisor mode booting (Vladimir Murzin)
- use compiler built-ins for fls and ffs (Nicolas Pitre)
* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: spectre-v1: mitigate user accesses
ARM: spectre-v1: use get_user() for __get_user()
ARM: use __inttype() in get_user()
ARM: oabi-compat: copy semops using __copy_from_user()
ARM: vfp: use __copy_from_user() when restoring VFP state
ARM: 8785/1: use compiler built-ins for ffs and fls
ARM: 8784/1: NOMMU: Allow enter in Hyp mode
ARM: 8783/1: NOMMU: Extend check for VBAR support
ARM: 8782/1: vfp: clean up arch/arm/vfp/Makefile
ARM: signal: copy registers using __copy_from_user()
ARM: tcm: ensure inline stub functions are marked static
ARM: 8779/1: add endianness option to LDFLAGS instead of LD
ARM: 8777/1: Hook up SYNC_CORE functionality for sys_membarrier()
diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt b/Documentation/features/sched/membarrier-sync-core/arch-support.txt
index dbdf629..c7858dd 100644
--- a/Documentation/features/sched/membarrier-sync-core/arch-support.txt
+++ b/Documentation/features/sched/membarrier-sync-core/arch-support.txt
@@ -5,10 +5,10 @@
#
# Architecture requirements
#
-# * arm64
+# * arm/arm64
#
-# Rely on eret context synchronization when returning from IPI handler, and
-# when returning to user-space.
+# Rely on implicit context synchronization as a result of exception return
+# when returning from IPI handler, and when returning to user-space.
#
# * x86
#
@@ -31,7 +31,7 @@
-----------------------
| alpha: | TODO |
| arc: | TODO |
- | arm: | TODO |
+ | arm: | ok |
| arm64: | ok |
| c6x: | TODO |
| h8300: | TODO |
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d7a8128..0f328d6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -9,6 +9,7 @@
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_KCOV
+ select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
select ARCH_HAS_PHYS_TO_DMA
select ARCH_HAS_SET_MEMORY
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index fc26c3d..62ebeae 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -46,12 +46,12 @@
KBUILD_CPPFLAGS += -mbig-endian
CHECKFLAGS += -D__ARMEB__
AS += -EB
-LD += -EB
+LDFLAGS += -EB
else
KBUILD_CPPFLAGS += -mlittle-endian
CHECKFLAGS += -D__ARMEL__
AS += -EL
-LD += -EL
+LDFLAGS += -EL
endif
#
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 0cd4dcc..b17ee03 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -460,6 +460,10 @@ THUMB( orr \reg , \reg , #PSR_T_BIT )
adds \tmp, \addr, #\size - 1
sbcccs \tmp, \tmp, \limit
bcs \bad
+#ifdef CONFIG_CPU_SPECTRE
+ movcs \addr, #0
+ csdb
+#endif
#endif
.endm
diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h
index 4cab9bb..c92e42a 100644
--- a/arch/arm/include/asm/bitops.h
+++ b/arch/arm/include/asm/bitops.h
@@ -215,7 +215,6 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset);
#if __LINUX_ARM_ARCH__ < 5
-#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/fls.h>
@@ -223,93 +222,20 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset);
#else
-static inline int constant_fls(int x)
-{
- int r = 32;
-
- if (!x)
- return 0;
- if (!(x & 0xffff0000u)) {
- x <<= 16;
- r -= 16;
- }
- if (!(x & 0xff000000u)) {
- x <<= 8;
- r -= 8;
- }
- if (!(x & 0xf0000000u)) {
- x <<= 4;
- r -= 4;
- }
- if (!(x & 0xc0000000u)) {
- x <<= 2;
- r -= 2;
- }
- if (!(x & 0x80000000u)) {
- x <<= 1;
- r -= 1;
- }
- return r;
-}
-
/*
- * On ARMv5 and above those functions can be implemented around the
- * clz instruction for much better code efficiency. __clz returns
- * the number of leading zeros, zero input will return 32, and
- * 0x80000000 will return 0.
+ * On ARMv5 and above, the gcc built-ins may rely on the clz instruction
+ * and produce optimal inlined code in all cases. On ARMv7 it is even
+ * better by also using the rbit instruction.
*/
-static inline unsigned int __clz(unsigned int x)
-{
- unsigned int ret;
-
- asm("clz\t%0, %1" : "=r" (ret) : "r" (x));
-
- return ret;
-}
-
-/*
- * fls() returns zero if the input is zero, otherwise returns the bit
- * position of the last set bit, where the LSB is 1 and MSB is 32.
- */
-static inline int fls(int x)
-{
- if (__builtin_constant_p(x))
- return constant_fls(x);
-
- return 32 - __clz(x);
-}
-
-/*
- * __fls() returns the bit position of the last bit set, where the
- * LSB is 0 and MSB is 31. Zero input is undefined.
- */
-static inline unsigned long __fls(unsigned long x)
-{
- return fls(x) - 1;
-}
-
-/*
- * ffs() returns zero if the input was zero, otherwise returns the bit
- * position of the first set bit, where the LSB is 1 and MSB is 32.
- */
-static inline int ffs(int x)
-{
- return fls(x & -x);
-}
-
-/*
- * __ffs() returns the bit position of the first bit set, where the
- * LSB is 0 and MSB is 31. Zero input is undefined.
- */
-static inline unsigned long __ffs(unsigned long x)
-{
- return ffs(x) - 1;
-}
-
-#define ffz(x) __ffs( ~(x) )
+#include <asm-generic/bitops/builtin-__fls.h>
+#include <asm-generic/bitops/builtin-__ffs.h>
+#include <asm-generic/bitops/builtin-fls.h>
+#include <asm-generic/bitops/builtin-ffs.h>
#endif
+#include <asm-generic/bitops/ffz.h>
+
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index e71cc35..9b37b6a 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -123,8 +123,8 @@ struct user_vfp_exc;
extern int vfp_preserve_user_clear_hwstate(struct user_vfp __user *,
struct user_vfp_exc __user *);
-extern int vfp_restore_user_hwstate(struct user_vfp __user *,
- struct user_vfp_exc __user *);
+extern int vfp_restore_user_hwstate(struct user_vfp *,
+ struct user_vfp_exc *);
#endif
/*
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 3d614e9..5451e1f 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -85,6 +85,13 @@ static inline void set_fs(mm_segment_t fs)
flag; })
/*
+ * This is a type: either unsigned long, if the argument fits into
+ * that type, or otherwise unsigned long long.
+ */
+#define __inttype(x) \
+ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
+
+/*
* Single-value transfer routines. They automatically use the right
* size if we just have the right pointer type. Note that the functions
* which read from user space (*get_*) need to take care not to leak
@@ -153,7 +160,7 @@ extern int __get_user_64t_4(void *);
({ \
unsigned long __limit = current_thread_info()->addr_limit - 1; \
register typeof(*(p)) __user *__p asm("r0") = (p); \
- register typeof(x) __r2 asm("r2"); \
+ register __inttype(x) __r2 asm("r2"); \
register unsigned long __l asm("r1") = __limit; \
register int __e asm("r0"); \
unsigned int __ua_flags = uaccess_save_and_enable(); \
@@ -243,6 +250,16 @@ static inline void set_fs(mm_segment_t fs)
#define user_addr_max() \
(uaccess_kernel() ? ~0UL : get_fs())
+#ifdef CONFIG_CPU_SPECTRE
+/*
+ * When mitigating Spectre variant 1, it is not worth fixing the non-
+ * verifying accessors, because we need to add verification of the
+ * address space there. Force these to use the standard get_user()
+ * version instead.
+ */
+#define __get_user(x, ptr) get_user(x, ptr)
+#else
+
/*
* The "__xxx" versions of the user access functions do not verify the
* address space - it must have been done previously with a separate
@@ -259,12 +276,6 @@ static inline void set_fs(mm_segment_t fs)
__gu_err; \
})
-#define __get_user_error(x, ptr, err) \
-({ \
- __get_user_err((x), (ptr), err); \
- (void) 0; \
-})
-
#define __get_user_err(x, ptr, err) \
do { \
unsigned long __gu_addr = (unsigned long)(ptr); \
@@ -324,6 +335,7 @@ do { \
#define __get_user_asm_word(x, addr, err) \
__get_user_asm(x, addr, err, ldr)
+#endif
#define __put_user_switch(x, ptr, __err, __fn) \
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S
index 7a9b869..ec29de2 100644
--- a/arch/arm/kernel/head-nommu.S
+++ b/arch/arm/kernel/head-nommu.S
@@ -53,7 +53,11 @@
THUMB(1: )
#endif
- setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
+#ifdef CONFIG_ARM_VIRT_EXT
+ bl __hyp_stub_install
+#endif
+ @ ensure svc mode and all interrupts masked
+ safe_svcmode_maskall r9
@ and irqs disabled
#if defined(CONFIG_CPU_CP15)
mrc p15, 0, r9, c0, c0 @ get processor id
@@ -89,7 +93,11 @@
* the processor type - there is no need to check the machine type
* as it has already been validated by the primary processor.
*/
- setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9
+#ifdef CONFIG_ARM_VIRT_EXT
+ bl __hyp_stub_install_secondary
+#endif
+ safe_svcmode_maskall r9
+
#ifndef CONFIG_CPU_CP15
ldr r9, =CONFIG_PROCESSOR_ID
#else
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index dec130e..b8f766c 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -150,22 +150,18 @@ static int preserve_vfp_context(struct vfp_sigframe __user *frame)
static int restore_vfp_context(char __user **auxp)
{
- struct vfp_sigframe __user *frame =
- (struct vfp_sigframe __user *)*auxp;
- unsigned long magic;
- unsigned long size;
- int err = 0;
+ struct vfp_sigframe frame;
+ int err;
- __get_user_error(magic, &frame->magic, err);
- __get_user_error(size, &frame->size, err);
-
+ err = __copy_from_user(&frame, *auxp, sizeof(frame));
if (err)
- return -EFAULT;
- if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE)
+ return err;
+
+ if (frame.magic != VFP_MAGIC || frame.size != VFP_STORAGE_SIZE)
return -EINVAL;
- *auxp += size;
- return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc);
+ *auxp += sizeof(frame);
+ return vfp_restore_user_hwstate(&frame.ufp, &frame.ufp_exc);
}
#endif
@@ -176,6 +172,7 @@ static int restore_vfp_context(char __user **auxp)
static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
{
+ struct sigcontext context;
char __user *aux;
sigset_t set;
int err;
@@ -184,23 +181,26 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
if (err == 0)
set_current_blocked(&set);
- __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err);
- __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err);
- __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err);
- __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err);
- __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err);
- __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err);
- __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err);
- __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err);
- __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err);
- __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err);
- __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err);
- __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err);
- __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err);
- __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err);
- __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err);
- __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err);
- __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err);
+ err |= __copy_from_user(&context, &sf->uc.uc_mcontext, sizeof(context));
+ if (err == 0) {
+ regs->ARM_r0 = context.arm_r0;
+ regs->ARM_r1 = context.arm_r1;
+ regs->ARM_r2 = context.arm_r2;
+ regs->ARM_r3 = context.arm_r3;
+ regs->ARM_r4 = context.arm_r4;
+ regs->ARM_r5 = context.arm_r5;
+ regs->ARM_r6 = context.arm_r6;
+ regs->ARM_r7 = context.arm_r7;
+ regs->ARM_r8 = context.arm_r8;
+ regs->ARM_r9 = context.arm_r9;
+ regs->ARM_r10 = context.arm_r10;
+ regs->ARM_fp = context.arm_fp;
+ regs->ARM_ip = context.arm_ip;
+ regs->ARM_sp = context.arm_sp;
+ regs->ARM_lr = context.arm_lr;
+ regs->ARM_pc = context.arm_pc;
+ regs->ARM_cpsr = context.arm_cpsr;
+ }
err |= !valid_user_regs(regs);
diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c
index 1df21a6..f0dd4b6 100644
--- a/arch/arm/kernel/sys_oabi-compat.c
+++ b/arch/arm/kernel/sys_oabi-compat.c
@@ -329,9 +329,11 @@ asmlinkage long sys_oabi_semtimedop(int semid,
return -ENOMEM;
err = 0;
for (i = 0; i < nsops; i++) {
- __get_user_error(sops[i].sem_num, &tsops->sem_num, err);
- __get_user_error(sops[i].sem_op, &tsops->sem_op, err);
- __get_user_error(sops[i].sem_flg, &tsops->sem_flg, err);
+ struct oabi_sembuf osb;
+ err |= __copy_from_user(&osb, tsops, sizeof(osb));
+ sops[i].sem_num = osb.sem_num;
+ sops[i].sem_op = osb.sem_op;
+ sops[i].sem_flg = osb.sem_flg;
tsops++;
}
if (timeout) {
diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S
index 7a4b060..a826df3 100644
--- a/arch/arm/lib/copy_from_user.S
+++ b/arch/arm/lib/copy_from_user.S
@@ -90,6 +90,15 @@
.text
ENTRY(arm_copy_from_user)
+#ifdef CONFIG_CPU_SPECTRE
+ get_thread_info r3
+ ldr r3, [r3, #TI_ADDR_LIMIT]
+ adds ip, r1, r2 @ ip=addr+size
+ sub r3, r3, #1 @ addr_limit - 1
+ cmpcc ip, r3 @ if (addr+size > addr_limit - 1)
+ movcs r1, #0 @ addr = NULL
+ csdb
+#endif
#include "copy_template.S"
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 96a7b6c..b169e58 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -702,7 +702,6 @@
config ARM_VIRT_EXT
bool
- depends on MMU
default y if CPU_V7
help
Enable the kernel to make use of the ARM Virtualization
diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c
index 5dd6c58..7d67c70 100644
--- a/arch/arm/mm/nommu.c
+++ b/arch/arm/mm/nommu.c
@@ -53,7 +53,8 @@ static inline bool security_extensions_enabled(void)
{
/* Check CPUID Identification Scheme before ID_PFR1 read */
if ((read_cpuid_id() & 0x000f0000) == 0x000f0000)
- return !!cpuid_feature_extract(CPUID_EXT_PFR1, 4);
+ return cpuid_feature_extract(CPUID_EXT_PFR1, 4) ||
+ cpuid_feature_extract(CPUID_EXT_PFR1, 20);
return 0;
}
diff --git a/arch/arm/mm/tcm.h b/arch/arm/mm/tcm.h
index 8015ad4..2410192 100644
--- a/arch/arm/mm/tcm.h
+++ b/arch/arm/mm/tcm.h
@@ -11,7 +11,7 @@
void __init tcm_init(void);
#else
/* No TCM support, just blank inlines to be optimized out */
-inline void tcm_init(void)
+static inline void tcm_init(void)
{
}
#endif
diff --git a/arch/arm/vfp/Makefile b/arch/arm/vfp/Makefile
index a81404c..94516c4 100644
--- a/arch/arm/vfp/Makefile
+++ b/arch/arm/vfp/Makefile
@@ -8,8 +8,5 @@
# asflags-y := -DDEBUG
KBUILD_AFLAGS :=$(KBUILD_AFLAGS:-msoft-float=-Wa,-mfpu=softvfp+vfp -mfloat-abi=soft)
-LDFLAGS +=--no-warn-mismatch
-obj-y += vfp.o
-
-vfp-$(CONFIG_VFP) += vfpmodule.o entry.o vfphw.o vfpsingle.o vfpdouble.o
+obj-y += vfpmodule.o entry.o vfphw.o vfpsingle.o vfpdouble.o
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 35d0f82..dc7e6b5 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -596,13 +596,11 @@ int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp,
}
/* Sanitise and restore the current VFP state from the provided structures. */
-int vfp_restore_user_hwstate(struct user_vfp __user *ufp,
- struct user_vfp_exc __user *ufp_exc)
+int vfp_restore_user_hwstate(struct user_vfp *ufp, struct user_vfp_exc *ufp_exc)
{
struct thread_info *thread = current_thread_info();
struct vfp_hard_struct *hwstate = &thread->vfpstate.hard;
unsigned long fpexc;
- int err = 0;
/* Disable VFP to avoid corrupting the new thread state. */
vfp_flush_hwstate(thread);
@@ -611,17 +609,16 @@ int vfp_restore_user_hwstate(struct user_vfp __user *ufp,
* Copy the floating point registers. There can be unused
* registers see asm/hwcap.h for details.
*/
- err |= __copy_from_user(&hwstate->fpregs, &ufp->fpregs,
- sizeof(hwstate->fpregs));
+ memcpy(&hwstate->fpregs, &ufp->fpregs, sizeof(hwstate->fpregs));
/*
* Copy the status and control register.
*/
- __get_user_error(hwstate->fpscr, &ufp->fpscr, err);
+ hwstate->fpscr = ufp->fpscr;
/*
* Sanitise and restore the exception registers.
*/
- __get_user_error(fpexc, &ufp_exc->fpexc, err);
+ fpexc = ufp_exc->fpexc;
/* Ensure the VFP is enabled. */
fpexc |= FPEXC_EN;
@@ -630,10 +627,10 @@ int vfp_restore_user_hwstate(struct user_vfp __user *ufp,
fpexc &= ~(FPEXC_EX | FPEXC_FP2V);
hwstate->fpexc = fpexc;
- __get_user_error(hwstate->fpinst, &ufp_exc->fpinst, err);
- __get_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err);
+ hwstate->fpinst = ufp_exc->fpinst;
+ hwstate->fpinst2 = ufp_exc->fpinst2;
- return err ? -EFAULT : 0;
+ return 0;
}
/*