#define CLBR_EAX (1 << 0)
#define CLBR_ECX (1 << 1)
#define CLBR_EDX (1 << 2)
+#define CLBR_EDI (1 << 3)
-#ifdef CONFIG_X86_64
-#define CLBR_RSI (1 << 3)
-#define CLBR_RDI (1 << 4)
+#ifdef CONFIG_X86_32
+/* CLBR_ANY should match all regs platform has. For i386, that's just it */
+#define CLBR_ANY ((1 << 4) - 1)
+
+#define CLBR_ARG_REGS (CLBR_EAX | CLBR_EDX | CLBR_ECX)
+#define CLBR_RET_REG (CLBR_EAX | CLBR_EDX)
+#define CLBR_SCRATCH (0)
+#else
+#define CLBR_RAX CLBR_EAX
+#define CLBR_RCX CLBR_ECX
+#define CLBR_RDX CLBR_EDX
+#define CLBR_RDI CLBR_EDI
+#define CLBR_RSI (1 << 4)
#define CLBR_R8 (1 << 5)
#define CLBR_R9 (1 << 6)
#define CLBR_R10 (1 << 7)
#define CLBR_R11 (1 << 8)
+
#define CLBR_ANY ((1 << 9) - 1)
+
+#define CLBR_ARG_REGS (CLBR_RDI | CLBR_RSI | CLBR_RDX | \
+ CLBR_RCX | CLBR_R8 | CLBR_R9)
+#define CLBR_RET_REG (CLBR_RAX)
+#define CLBR_SCRATCH (CLBR_R10 | CLBR_R11)
+
#include <asm/desc_defs.h>
-#else
-/* CLBR_ANY should match all regs platform has. For i386, that's just it */
-#define CLBR_ANY ((1 << 3) - 1)
#endif /* X86_64 */
+#define CLBR_CALLEE_SAVE ((CLBR_ARG_REGS | CLBR_SCRATCH) & ~CLBR_RET_REG)
+
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/cpumask.h>
struct mm_struct;
struct desc_struct;
+/*
+ * Wrapper type for pointers to code which uses the non-standard
+ * calling convention. See PV_CALL_SAVE_REGS_THUNK below.
+ */
+struct paravirt_callee_save {
+ void *func;
+};
+
/* general info */
struct pv_info {
unsigned int kernel_rpl;
* expected to use X86_EFLAGS_IF; all other bits
* returned from save_fl are undefined, and may be ignored by
* restore_fl.
+ *
+ * NOTE: These functions callers expect the callee to preserve
+ * more registers than the standard C calling convention.
*/
- unsigned long (*save_fl)(void);
- void (*restore_fl)(unsigned long);
- void (*irq_disable)(void);
- void (*irq_enable)(void);
+ struct paravirt_callee_save save_fl;
+ struct paravirt_callee_save restore_fl;
+ struct paravirt_callee_save irq_disable;
+ struct paravirt_callee_save irq_enable;
+
void (*safe_halt)(void);
void (*halt)(void);
void (*flush_tlb_user)(void);
void (*flush_tlb_kernel)(void);
void (*flush_tlb_single)(unsigned long addr);
- void (*flush_tlb_others)(const cpumask_t *cpus, struct mm_struct *mm,
+ void (*flush_tlb_others)(const struct cpumask *cpus,
+ struct mm_struct *mm,
unsigned long va);
/* Hooks for allocating and freeing a pagetable top-level */
void (*ptep_modify_prot_commit)(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte);
- pteval_t (*pte_val)(pte_t);
- pteval_t (*pte_flags)(pte_t);
- pte_t (*make_pte)(pteval_t pte);
+ struct paravirt_callee_save pte_val;
+ struct paravirt_callee_save make_pte;
- pgdval_t (*pgd_val)(pgd_t);
- pgd_t (*make_pgd)(pgdval_t pgd);
+ struct paravirt_callee_save pgd_val;
+ struct paravirt_callee_save make_pgd;
#if PAGETABLE_LEVELS >= 3
#ifdef CONFIG_X86_PAE
void (*set_pud)(pud_t *pudp, pud_t pudval);
- pmdval_t (*pmd_val)(pmd_t);
- pmd_t (*make_pmd)(pmdval_t pmd);
+ struct paravirt_callee_save pmd_val;
+ struct paravirt_callee_save make_pmd;
#if PAGETABLE_LEVELS == 4
- pudval_t (*pud_val)(pud_t);
- pud_t (*make_pud)(pudval_t pud);
+ struct paravirt_callee_save pud_val;
+ struct paravirt_callee_save make_pud;
void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);
#endif /* PAGETABLE_LEVELS == 4 */
asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")
unsigned paravirt_patch_nop(void);
+unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len);
+unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len);
unsigned paravirt_patch_ignore(unsigned len);
unsigned paravirt_patch_call(void *insnbuf,
const void *target, u16 tgt_clobbers,
* makes sure the incoming and outgoing types are always correct.
*/
#ifdef CONFIG_X86_32
-#define PVOP_VCALL_ARGS unsigned long __eax, __edx, __ecx
+#define PVOP_VCALL_ARGS \
+ unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx
#define PVOP_CALL_ARGS PVOP_VCALL_ARGS
+
+#define PVOP_CALL_ARG1(x) "a" ((unsigned long)(x))
+#define PVOP_CALL_ARG2(x) "d" ((unsigned long)(x))
+#define PVOP_CALL_ARG3(x) "c" ((unsigned long)(x))
+
#define PVOP_VCALL_CLOBBERS "=a" (__eax), "=d" (__edx), \
"=c" (__ecx)
#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS
+
+#define PVOP_VCALLEE_CLOBBERS "=a" (__eax), "=d" (__edx)
+#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
+
#define EXTRA_CLOBBERS
#define VEXTRA_CLOBBERS
-#else
-#define PVOP_VCALL_ARGS unsigned long __edi, __esi, __edx, __ecx
+#else /* CONFIG_X86_64 */
+#define PVOP_VCALL_ARGS \
+ unsigned long __edi = __edi, __esi = __esi, \
+ __edx = __edx, __ecx = __ecx
#define PVOP_CALL_ARGS PVOP_VCALL_ARGS, __eax
+
+#define PVOP_CALL_ARG1(x) "D" ((unsigned long)(x))
+#define PVOP_CALL_ARG2(x) "S" ((unsigned long)(x))
+#define PVOP_CALL_ARG3(x) "d" ((unsigned long)(x))
+#define PVOP_CALL_ARG4(x) "c" ((unsigned long)(x))
+
#define PVOP_VCALL_CLOBBERS "=D" (__edi), \
"=S" (__esi), "=d" (__edx), \
"=c" (__ecx)
-
#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS, "=a" (__eax)
+#define PVOP_VCALLEE_CLOBBERS "=a" (__eax)
+#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
+
#define EXTRA_CLOBBERS , "r8", "r9", "r10", "r11"
#define VEXTRA_CLOBBERS , "rax", "r8", "r9", "r10", "r11"
-#endif
+#endif /* CONFIG_X86_32 */
#ifdef CONFIG_PARAVIRT_DEBUG
#define PVOP_TEST_NULL(op) BUG_ON(op == NULL)
#define PVOP_TEST_NULL(op) ((void)op)
#endif
-#define __PVOP_CALL(rettype, op, pre, post, ...) \
+#define ____PVOP_CALL(rettype, op, clbr, call_clbr, extra_clbr, \
+ pre, post, ...) \
({ \
rettype __ret; \
- PVOP_CALL_ARGS; \
+ PVOP_CALL_ARGS; \
PVOP_TEST_NULL(op); \
/* This is 32-bit specific, but is okay in 64-bit */ \
/* since this condition will never hold */ \
asm volatile(pre \
paravirt_alt(PARAVIRT_CALL) \
post \
- : PVOP_CALL_CLOBBERS \
+ : call_clbr \
: paravirt_type(op), \
- paravirt_clobber(CLBR_ANY), \
+ paravirt_clobber(clbr), \
##__VA_ARGS__ \
- : "memory", "cc" EXTRA_CLOBBERS); \
+ : "memory", "cc" extra_clbr); \
__ret = (rettype)((((u64)__edx) << 32) | __eax); \
} else { \
asm volatile(pre \
paravirt_alt(PARAVIRT_CALL) \
post \
- : PVOP_CALL_CLOBBERS \
+ : call_clbr \
: paravirt_type(op), \
- paravirt_clobber(CLBR_ANY), \
+ paravirt_clobber(clbr), \
##__VA_ARGS__ \
- : "memory", "cc" EXTRA_CLOBBERS); \
+ : "memory", "cc" extra_clbr); \
__ret = (rettype)__eax; \
} \
__ret; \
})
-#define __PVOP_VCALL(op, pre, post, ...) \
+
+#define __PVOP_CALL(rettype, op, pre, post, ...) \
+ ____PVOP_CALL(rettype, op, CLBR_ANY, PVOP_CALL_CLOBBERS, \
+ EXTRA_CLOBBERS, pre, post, ##__VA_ARGS__)
+
+#define __PVOP_CALLEESAVE(rettype, op, pre, post, ...) \
+ ____PVOP_CALL(rettype, op.func, CLBR_RET_REG, \
+ PVOP_CALLEE_CLOBBERS, , \
+ pre, post, ##__VA_ARGS__)
+
+
+#define ____PVOP_VCALL(op, clbr, call_clbr, extra_clbr, pre, post, ...) \
({ \
PVOP_VCALL_ARGS; \
PVOP_TEST_NULL(op); \
asm volatile(pre \
paravirt_alt(PARAVIRT_CALL) \
post \
- : PVOP_VCALL_CLOBBERS \
+ : call_clbr \
: paravirt_type(op), \
- paravirt_clobber(CLBR_ANY), \
+ paravirt_clobber(clbr), \
##__VA_ARGS__ \
- : "memory", "cc" VEXTRA_CLOBBERS); \
+ : "memory", "cc" extra_clbr); \
})
+#define __PVOP_VCALL(op, pre, post, ...) \
+ ____PVOP_VCALL(op, CLBR_ANY, PVOP_VCALL_CLOBBERS, \
+ VEXTRA_CLOBBERS, \
+ pre, post, ##__VA_ARGS__)
+
+#define __PVOP_VCALLEESAVE(rettype, op, pre, post, ...) \
+ ____PVOP_CALL(rettype, op.func, CLBR_RET_REG, \
+ PVOP_VCALLEE_CLOBBERS, , \
+ pre, post, ##__VA_ARGS__)
+
+
+
#define PVOP_CALL0(rettype, op) \
__PVOP_CALL(rettype, op, "", "")
#define PVOP_VCALL0(op) \
__PVOP_VCALL(op, "", "")
+#define PVOP_CALLEE0(rettype, op) \
+ __PVOP_CALLEESAVE(rettype, op, "", "")
+#define PVOP_VCALLEE0(op) \
+ __PVOP_VCALLEESAVE(op, "", "")
+
+
#define PVOP_CALL1(rettype, op, arg1) \
- __PVOP_CALL(rettype, op, "", "", "0" ((unsigned long)(arg1)))
+ __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1))
#define PVOP_VCALL1(op, arg1) \
- __PVOP_VCALL(op, "", "", "0" ((unsigned long)(arg1)))
+ __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1))
+
+#define PVOP_CALLEE1(rettype, op, arg1) \
+ __PVOP_CALLEESAVE(rettype, op, "", "", PVOP_CALL_ARG1(arg1))
+#define PVOP_VCALLEE1(op, arg1) \
+ __PVOP_VCALLEESAVE(op, "", "", PVOP_CALL_ARG1(arg1))
+
#define PVOP_CALL2(rettype, op, arg1, arg2) \
- __PVOP_CALL(rettype, op, "", "", "0" ((unsigned long)(arg1)), \
- "1" ((unsigned long)(arg2)))
+ __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2))
#define PVOP_VCALL2(op, arg1, arg2) \
- __PVOP_VCALL(op, "", "", "0" ((unsigned long)(arg1)), \
- "1" ((unsigned long)(arg2)))
+ __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2))
+
+#define PVOP_CALLEE2(rettype, op, arg1, arg2) \
+ __PVOP_CALLEESAVE(rettype, op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2))
+#define PVOP_VCALLEE2(op, arg1, arg2) \
+ __PVOP_VCALLEESAVE(op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2))
+
#define PVOP_CALL3(rettype, op, arg1, arg2, arg3) \
- __PVOP_CALL(rettype, op, "", "", "0" ((unsigned long)(arg1)), \
- "1"((unsigned long)(arg2)), "2"((unsigned long)(arg3)))
+ __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
#define PVOP_VCALL3(op, arg1, arg2, arg3) \
- __PVOP_VCALL(op, "", "", "0" ((unsigned long)(arg1)), \
- "1"((unsigned long)(arg2)), "2"((unsigned long)(arg3)))
+ __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1), \
+ PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
/* This is the only difference in x86_64. We can make it much simpler */
#ifdef CONFIG_X86_32
#define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4) \
__PVOP_CALL(rettype, op, \
"push %[_arg4];", "lea 4(%%esp),%%esp;", \
- "0" ((u32)(arg1)), "1" ((u32)(arg2)), \
- "2" ((u32)(arg3)), [_arg4] "mr" ((u32)(arg4)))
+ PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2), \
+ PVOP_CALL_ARG3(arg3), [_arg4] "mr" ((u32)(arg4)))
#define PVOP_VCALL4(op, arg1, arg2, arg3, arg4) \
__PVOP_VCALL(op, \
"push %[_arg4];", "lea 4(%%esp),%%esp;", \
"2" ((u32)(arg3)), [_arg4] "mr" ((u32)(arg4)))
#else
#define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4) \
- __PVOP_CALL(rettype, op, "", "", "0" ((unsigned long)(arg1)), \
- "1"((unsigned long)(arg2)), "2"((unsigned long)(arg3)), \
- "3"((unsigned long)(arg4)))
+ __PVOP_CALL(rettype, op, "", "", \
+ PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2), \
+ PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
#define PVOP_VCALL4(op, arg1, arg2, arg3, arg4) \
- __PVOP_VCALL(op, "", "", "0" ((unsigned long)(arg1)), \
- "1"((unsigned long)(arg2)), "2"((unsigned long)(arg3)), \
- "3"((unsigned long)(arg4)))
+ __PVOP_VCALL(op, "", "", \
+ PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2), \
+ PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
#endif
static inline int paravirt_enabled(void)
PVOP_VCALL1(pv_mmu_ops.flush_tlb_single, addr);
}
-static inline void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
+static inline void flush_tlb_others(const struct cpumask *cpumask,
+ struct mm_struct *mm,
unsigned long va)
{
- PVOP_VCALL3(pv_mmu_ops.flush_tlb_others, &cpumask, mm, va);
+ PVOP_VCALL3(pv_mmu_ops.flush_tlb_others, cpumask, mm, va);
}
static inline int paravirt_pgd_alloc(struct mm_struct *mm)
pteval_t ret;
if (sizeof(pteval_t) > sizeof(long))
- ret = PVOP_CALL2(pteval_t,
- pv_mmu_ops.make_pte,
- val, (u64)val >> 32);
+ ret = PVOP_CALLEE2(pteval_t,
+ pv_mmu_ops.make_pte,
+ val, (u64)val >> 32);
else
- ret = PVOP_CALL1(pteval_t,
- pv_mmu_ops.make_pte,
- val);
+ ret = PVOP_CALLEE1(pteval_t,
+ pv_mmu_ops.make_pte,
+ val);
return (pte_t) { .pte = ret };
}
pteval_t ret;
if (sizeof(pteval_t) > sizeof(long))
- ret = PVOP_CALL2(pteval_t, pv_mmu_ops.pte_val,
- pte.pte, (u64)pte.pte >> 32);
- else
- ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_val,
- pte.pte);
-
- return ret;
-}
-
-static inline pteval_t pte_flags(pte_t pte)
-{
- pteval_t ret;
-
- if (sizeof(pteval_t) > sizeof(long))
- ret = PVOP_CALL2(pteval_t, pv_mmu_ops.pte_flags,
- pte.pte, (u64)pte.pte >> 32);
+ ret = PVOP_CALLEE2(pteval_t, pv_mmu_ops.pte_val,
+ pte.pte, (u64)pte.pte >> 32);
else
- ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_flags,
- pte.pte);
+ ret = PVOP_CALLEE1(pteval_t, pv_mmu_ops.pte_val,
+ pte.pte);
-#ifdef CONFIG_PARAVIRT_DEBUG
- BUG_ON(ret & PTE_PFN_MASK);
-#endif
return ret;
}
pgdval_t ret;
if (sizeof(pgdval_t) > sizeof(long))
- ret = PVOP_CALL2(pgdval_t, pv_mmu_ops.make_pgd,
- val, (u64)val >> 32);
+ ret = PVOP_CALLEE2(pgdval_t, pv_mmu_ops.make_pgd,
+ val, (u64)val >> 32);
else
- ret = PVOP_CALL1(pgdval_t, pv_mmu_ops.make_pgd,
- val);
+ ret = PVOP_CALLEE1(pgdval_t, pv_mmu_ops.make_pgd,
+ val);
return (pgd_t) { ret };
}
pgdval_t ret;
if (sizeof(pgdval_t) > sizeof(long))
- ret = PVOP_CALL2(pgdval_t, pv_mmu_ops.pgd_val,
- pgd.pgd, (u64)pgd.pgd >> 32);
+ ret = PVOP_CALLEE2(pgdval_t, pv_mmu_ops.pgd_val,
+ pgd.pgd, (u64)pgd.pgd >> 32);
else
- ret = PVOP_CALL1(pgdval_t, pv_mmu_ops.pgd_val,
- pgd.pgd);
+ ret = PVOP_CALLEE1(pgdval_t, pv_mmu_ops.pgd_val,
+ pgd.pgd);
return ret;
}
pmdval_t ret;
if (sizeof(pmdval_t) > sizeof(long))
- ret = PVOP_CALL2(pmdval_t, pv_mmu_ops.make_pmd,
- val, (u64)val >> 32);
+ ret = PVOP_CALLEE2(pmdval_t, pv_mmu_ops.make_pmd,
+ val, (u64)val >> 32);
else
- ret = PVOP_CALL1(pmdval_t, pv_mmu_ops.make_pmd,
- val);
+ ret = PVOP_CALLEE1(pmdval_t, pv_mmu_ops.make_pmd,
+ val);
return (pmd_t) { ret };
}
pmdval_t ret;
if (sizeof(pmdval_t) > sizeof(long))
- ret = PVOP_CALL2(pmdval_t, pv_mmu_ops.pmd_val,
- pmd.pmd, (u64)pmd.pmd >> 32);
+ ret = PVOP_CALLEE2(pmdval_t, pv_mmu_ops.pmd_val,
+ pmd.pmd, (u64)pmd.pmd >> 32);
else
- ret = PVOP_CALL1(pmdval_t, pv_mmu_ops.pmd_val,
- pmd.pmd);
+ ret = PVOP_CALLEE1(pmdval_t, pv_mmu_ops.pmd_val,
+ pmd.pmd);
return ret;
}
pudval_t ret;
if (sizeof(pudval_t) > sizeof(long))
- ret = PVOP_CALL2(pudval_t, pv_mmu_ops.make_pud,
- val, (u64)val >> 32);
+ ret = PVOP_CALLEE2(pudval_t, pv_mmu_ops.make_pud,
+ val, (u64)val >> 32);
else
- ret = PVOP_CALL1(pudval_t, pv_mmu_ops.make_pud,
- val);
+ ret = PVOP_CALLEE1(pudval_t, pv_mmu_ops.make_pud,
+ val);
return (pud_t) { ret };
}
pudval_t ret;
if (sizeof(pudval_t) > sizeof(long))
- ret = PVOP_CALL2(pudval_t, pv_mmu_ops.pud_val,
- pud.pud, (u64)pud.pud >> 32);
+ ret = PVOP_CALLEE2(pudval_t, pv_mmu_ops.pud_val,
+ pud.pud, (u64)pud.pud >> 32);
else
- ret = PVOP_CALL1(pudval_t, pv_mmu_ops.pud_val,
- pud.pud);
+ ret = PVOP_CALLEE1(pudval_t, pv_mmu_ops.pud_val,
+ pud.pud);
return ret;
}
}
void _paravirt_nop(void);
+u32 _paravirt_ident_32(u32);
+u64 _paravirt_ident_64(u64);
+
#define paravirt_nop ((void *)_paravirt_nop)
- void paravirt_use_bytelocks(void);
-
#ifdef CONFIG_SMP
static inline int __raw_spin_is_locked(struct raw_spinlock *lock)
__parainstructions_end[];
#ifdef CONFIG_X86_32
-#define PV_SAVE_REGS "pushl %%ecx; pushl %%edx;"
-#define PV_RESTORE_REGS "popl %%edx; popl %%ecx"
+#define PV_SAVE_REGS "pushl %ecx; pushl %edx;"
+#define PV_RESTORE_REGS "popl %edx; popl %ecx;"
+
+/* save and restore all caller-save registers, except return value */
+#define PV_SAVE_ALL_CALLER_REGS "pushl %ecx;"
+#define PV_RESTORE_ALL_CALLER_REGS "popl %ecx;"
+
#define PV_FLAGS_ARG "0"
#define PV_EXTRA_CLOBBERS
#define PV_VEXTRA_CLOBBERS
#else
+/* save and restore all caller-save registers, except return value */
+#define PV_SAVE_ALL_CALLER_REGS \
+ "push %rcx;" \
+ "push %rdx;" \
+ "push %rsi;" \
+ "push %rdi;" \
+ "push %r8;" \
+ "push %r9;" \
+ "push %r10;" \
+ "push %r11;"
+#define PV_RESTORE_ALL_CALLER_REGS \
+ "pop %r11;" \
+ "pop %r10;" \
+ "pop %r9;" \
+ "pop %r8;" \
+ "pop %rdi;" \
+ "pop %rsi;" \
+ "pop %rdx;" \
+ "pop %rcx;"
+
/* We save some registers, but all of them, that's too much. We clobber all
* caller saved registers but the argument parameter */
#define PV_SAVE_REGS "pushq %%rdi;"
#define PV_FLAGS_ARG "D"
#endif
+/*
+ * Generate a thunk around a function which saves all caller-save
+ * registers except for the return value. This allows C functions to
+ * be called from assembler code where fewer than normal registers are
+ * available. It may also help code generation around calls from C
+ * code if the common case doesn't use many registers.
+ *
+ * When a callee is wrapped in a thunk, the caller can assume that all
+ * arg regs and all scratch registers are preserved across the
+ * call. The return value in rax/eax will not be saved, even for void
+ * functions.
+ */
+#define PV_CALLEE_SAVE_REGS_THUNK(func) \
+ extern typeof(func) __raw_callee_save_##func; \
+ static void *__##func##__ __used = func; \
+ \
+ asm(".pushsection .text;" \
+ "__raw_callee_save_" #func ": " \
+ PV_SAVE_ALL_CALLER_REGS \
+ "call " #func ";" \
+ PV_RESTORE_ALL_CALLER_REGS \
+ "ret;" \
+ ".popsection")
+
+/* Get a reference to a callee-save function */
+#define PV_CALLEE_SAVE(func) \
+ ((struct paravirt_callee_save) { __raw_callee_save_##func })
+
+/* Promise that "func" already uses the right calling convention */
+#define __PV_IS_CALLEE_SAVE(func) \
+ ((struct paravirt_callee_save) { func })
+
static inline unsigned long __raw_local_save_flags(void)
{
unsigned long f;
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: paravirt_type(pv_irq_ops.save_fl),
paravirt_clobber(CLBR_EAX)
- : "memory", "cc" PV_VEXTRA_CLOBBERS);
+ : "memory", "cc");
return f;
}
static inline void raw_local_irq_restore(unsigned long f)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: PV_FLAGS_ARG(f),
paravirt_type(pv_irq_ops.restore_fl),
paravirt_clobber(CLBR_EAX)
- : "memory", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "cc");
}
static inline void raw_local_irq_disable(void)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_disable),
paravirt_clobber(CLBR_EAX)
- : "memory", "eax", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "eax", "cc");
}
static inline void raw_local_irq_enable(void)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_enable),
paravirt_clobber(CLBR_EAX)
- : "memory", "eax", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "eax", "cc");
}
static inline unsigned long __raw_local_irq_save(void)
.popsection
+#define COND_PUSH(set, mask, reg) \
+ .if ((~(set)) & mask); push %reg; .endif
+#define COND_POP(set, mask, reg) \
+ .if ((~(set)) & mask); pop %reg; .endif
+
#ifdef CONFIG_X86_64
-#define PV_SAVE_REGS \
- push %rax; \
- push %rcx; \
- push %rdx; \
- push %rsi; \
- push %rdi; \
- push %r8; \
- push %r9; \
- push %r10; \
- push %r11
-#define PV_RESTORE_REGS \
- pop %r11; \
- pop %r10; \
- pop %r9; \
- pop %r8; \
- pop %rdi; \
- pop %rsi; \
- pop %rdx; \
- pop %rcx; \
- pop %rax
+
+#define PV_SAVE_REGS(set) \
+ COND_PUSH(set, CLBR_RAX, rax); \
+ COND_PUSH(set, CLBR_RCX, rcx); \
+ COND_PUSH(set, CLBR_RDX, rdx); \
+ COND_PUSH(set, CLBR_RSI, rsi); \
+ COND_PUSH(set, CLBR_RDI, rdi); \
+ COND_PUSH(set, CLBR_R8, r8); \
+ COND_PUSH(set, CLBR_R9, r9); \
+ COND_PUSH(set, CLBR_R10, r10); \
+ COND_PUSH(set, CLBR_R11, r11)
+#define PV_RESTORE_REGS(set) \
+ COND_POP(set, CLBR_R11, r11); \
+ COND_POP(set, CLBR_R10, r10); \
+ COND_POP(set, CLBR_R9, r9); \
+ COND_POP(set, CLBR_R8, r8); \
+ COND_POP(set, CLBR_RDI, rdi); \
+ COND_POP(set, CLBR_RSI, rsi); \
+ COND_POP(set, CLBR_RDX, rdx); \
+ COND_POP(set, CLBR_RCX, rcx); \
+ COND_POP(set, CLBR_RAX, rax)
+
#define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 8)
#define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .quad, 8)
#define PARA_INDIRECT(addr) *addr(%rip)
#else
-#define PV_SAVE_REGS pushl %eax; pushl %edi; pushl %ecx; pushl %edx
-#define PV_RESTORE_REGS popl %edx; popl %ecx; popl %edi; popl %eax
+#define PV_SAVE_REGS(set) \
+ COND_PUSH(set, CLBR_EAX, eax); \
+ COND_PUSH(set, CLBR_EDI, edi); \
+ COND_PUSH(set, CLBR_ECX, ecx); \
+ COND_PUSH(set, CLBR_EDX, edx)
+#define PV_RESTORE_REGS(set) \
+ COND_POP(set, CLBR_EDX, edx); \
+ COND_POP(set, CLBR_ECX, ecx); \
+ COND_POP(set, CLBR_EDI, edi); \
+ COND_POP(set, CLBR_EAX, eax)
+
#define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 4)
#define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .long, 4)
#define PARA_INDIRECT(addr) *%cs:addr
#define DISABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \
- PV_SAVE_REGS; \
+ PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_disable); \
- PV_RESTORE_REGS;) \
+ PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#define ENABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_enable), clobbers, \
- PV_SAVE_REGS; \
+ PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \
- PV_RESTORE_REGS;)
+ PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#define USERGS_SYSRET32 \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_usergs_sysret32), \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_swapgs), CLBR_NONE, \
swapgs)
+/*
+ * Note: swapgs is very special, and in practise is either going to be
+ * implemented with a single "swapgs" instruction or something very
+ * special. Either way, we don't need to save any registers for
+ * it.
+ */
#define SWAPGS \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_swapgs), CLBR_NONE, \
- PV_SAVE_REGS; \
- call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs); \
- PV_RESTORE_REGS \
+ call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs) \
)
#define GET_CR2_INTO_RCX \
#endif
#define COPY(x) { \
- err |= __get_user(regs->x, &sc->x); \
+ get_user_ex(regs->x, &sc->x); \
}
#define COPY_SEG(seg) { \
unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
+ get_user_ex(tmp, &sc->seg); \
regs->seg = tmp; \
}
#define COPY_SEG_CPL3(seg) { \
unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
+ get_user_ex(tmp, &sc->seg); \
regs->seg = tmp | 3; \
}
#define GET_SEG(seg) { \
unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
+ get_user_ex(tmp, &sc->seg); \
loadsegment(seg, tmp); \
}
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
+ get_user_try {
+
#ifdef CONFIG_X86_32
- GET_SEG(gs);
- COPY_SEG(fs);
- COPY_SEG(es);
- COPY_SEG(ds);
+ GET_SEG(gs);
+ COPY_SEG(fs);
+ COPY_SEG(es);
+ COPY_SEG(ds);
#endif /* CONFIG_X86_32 */
- COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
- COPY(dx); COPY(cx); COPY(ip);
+ COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
+ COPY(dx); COPY(cx); COPY(ip);
#ifdef CONFIG_X86_64
- COPY(r8);
- COPY(r9);
- COPY(r10);
- COPY(r11);
- COPY(r12);
- COPY(r13);
- COPY(r14);
- COPY(r15);
+ COPY(r8);
+ COPY(r9);
+ COPY(r10);
+ COPY(r11);
+ COPY(r12);
+ COPY(r13);
+ COPY(r14);
+ COPY(r15);
#endif /* CONFIG_X86_64 */
#ifdef CONFIG_X86_32
- COPY_SEG_CPL3(cs);
- COPY_SEG_CPL3(ss);
+ COPY_SEG_CPL3(cs);
+ COPY_SEG_CPL3(ss);
#else /* !CONFIG_X86_32 */
- /* Kernel saves and restores only the CS segment register on signals,
- * which is the bare minimum needed to allow mixed 32/64-bit code.
- * App's signal handler can save/restore other segments if needed. */
- COPY_SEG_CPL3(cs);
+ /* Kernel saves and restores only the CS segment register on signals,
+ * which is the bare minimum needed to allow mixed 32/64-bit code.
+ * App's signal handler can save/restore other segments if needed. */
+ COPY_SEG_CPL3(cs);
#endif /* CONFIG_X86_32 */
- err |= __get_user(tmpflags, &sc->flags);
- regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
- regs->orig_ax = -1; /* disable syscall checks */
+ get_user_ex(tmpflags, &sc->flags);
+ regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
+ regs->orig_ax = -1; /* disable syscall checks */
+
+ get_user_ex(buf, &sc->fpstate);
+ err |= restore_i387_xstate(buf);
- err |= __get_user(buf, &sc->fpstate);
- err |= restore_i387_xstate(buf);
+ get_user_ex(*pax, &sc->ax);
+ } get_user_catch(err);
- err |= __get_user(*pax, &sc->ax);
return err;
}
{
int err = 0;
- #ifdef CONFIG_X86_32
- {
- unsigned int tmp;
+ put_user_try {
- savesegment(gs, tmp);
- err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
- }
- err |= __put_user(regs->fs, (unsigned int __user *)&sc->fs);
- err |= __put_user(regs->es, (unsigned int __user *)&sc->es);
- err |= __put_user(regs->ds, (unsigned int __user *)&sc->ds);
+ #ifdef CONFIG_X86_32
+ {
+ unsigned int tmp;
+
+ savesegment(gs, tmp);
+ put_user_ex(tmp, (unsigned int __user *)&sc->gs);
+ }
+ put_user_ex(regs->fs, (unsigned int __user *)&sc->fs);
+ put_user_ex(regs->es, (unsigned int __user *)&sc->es);
+ put_user_ex(regs->ds, (unsigned int __user *)&sc->ds);
#endif /* CONFIG_X86_32 */
- err |= __put_user(regs->di, &sc->di);
- err |= __put_user(regs->si, &sc->si);
- err |= __put_user(regs->bp, &sc->bp);
- err |= __put_user(regs->sp, &sc->sp);
- err |= __put_user(regs->bx, &sc->bx);
- err |= __put_user(regs->dx, &sc->dx);
- err |= __put_user(regs->cx, &sc->cx);
- err |= __put_user(regs->ax, &sc->ax);
+ put_user_ex(regs->di, &sc->di);
+ put_user_ex(regs->si, &sc->si);
+ put_user_ex(regs->bp, &sc->bp);
+ put_user_ex(regs->sp, &sc->sp);
+ put_user_ex(regs->bx, &sc->bx);
+ put_user_ex(regs->dx, &sc->dx);
+ put_user_ex(regs->cx, &sc->cx);
+ put_user_ex(regs->ax, &sc->ax);
#ifdef CONFIG_X86_64
- err |= __put_user(regs->r8, &sc->r8);
- err |= __put_user(regs->r9, &sc->r9);
- err |= __put_user(regs->r10, &sc->r10);
- err |= __put_user(regs->r11, &sc->r11);
- err |= __put_user(regs->r12, &sc->r12);
- err |= __put_user(regs->r13, &sc->r13);
- err |= __put_user(regs->r14, &sc->r14);
- err |= __put_user(regs->r15, &sc->r15);
+ put_user_ex(regs->r8, &sc->r8);
+ put_user_ex(regs->r9, &sc->r9);
+ put_user_ex(regs->r10, &sc->r10);
+ put_user_ex(regs->r11, &sc->r11);
+ put_user_ex(regs->r12, &sc->r12);
+ put_user_ex(regs->r13, &sc->r13);
+ put_user_ex(regs->r14, &sc->r14);
+ put_user_ex(regs->r15, &sc->r15);
#endif /* CONFIG_X86_64 */
- err |= __put_user(current->thread.trap_no, &sc->trapno);
- err |= __put_user(current->thread.error_code, &sc->err);
- err |= __put_user(regs->ip, &sc->ip);
+ put_user_ex(current->thread.trap_no, &sc->trapno);
+ put_user_ex(current->thread.error_code, &sc->err);
+ put_user_ex(regs->ip, &sc->ip);
#ifdef CONFIG_X86_32
- err |= __put_user(regs->cs, (unsigned int __user *)&sc->cs);
- err |= __put_user(regs->flags, &sc->flags);
- err |= __put_user(regs->sp, &sc->sp_at_signal);
- err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss);
+ put_user_ex(regs->cs, (unsigned int __user *)&sc->cs);
+ put_user_ex(regs->flags, &sc->flags);
+ put_user_ex(regs->sp, &sc->sp_at_signal);
+ put_user_ex(regs->ss, (unsigned int __user *)&sc->ss);
#else /* !CONFIG_X86_32 */
- err |= __put_user(regs->flags, &sc->flags);
- err |= __put_user(regs->cs, &sc->cs);
- err |= __put_user(0, &sc->gs);
- err |= __put_user(0, &sc->fs);
+ put_user_ex(regs->flags, &sc->flags);
+ put_user_ex(regs->cs, &sc->cs);
+ put_user_ex(0, &sc->gs);
+ put_user_ex(0, &sc->fs);
#endif /* CONFIG_X86_32 */
- err |= __put_user(fpstate, &sc->fpstate);
+ put_user_ex(fpstate, &sc->fpstate);
- /* non-iBCS2 extensions.. */
- err |= __put_user(mask, &sc->oldmask);
- err |= __put_user(current->thread.cr2, &sc->cr2);
+ /* non-iBCS2 extensions.. */
+ put_user_ex(mask, &sc->oldmask);
+ put_user_ex(current->thread.cr2, &sc->cr2);
+ } put_user_catch(err);
return err;
}
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
return -EFAULT;
- err |= __put_user(sig, &frame->sig);
- err |= __put_user(&frame->info, &frame->pinfo);
- err |= __put_user(&frame->uc, &frame->puc);
- err |= copy_siginfo_to_user(&frame->info, info);
- if (err)
- return -EFAULT;
-
- /* Create the ucontext. */
- if (cpu_has_xsave)
- err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
- else
- err |= __put_user(0, &frame->uc.uc_flags);
- err |= __put_user(0, &frame->uc.uc_link);
- err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
- err |= __put_user(sas_ss_flags(regs->sp),
- &frame->uc.uc_stack.ss_flags);
- err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
- regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
- if (err)
- return -EFAULT;
-
- /* Set up to return from userspace. */
- restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
- if (ka->sa.sa_flags & SA_RESTORER)
- restorer = ka->sa.sa_restorer;
- err |= __put_user(restorer, &frame->pretcode);
-
- /*
- * This is movl $__NR_rt_sigreturn, %ax ; int $0x80
- *
- * WE DO NOT USE IT ANY MORE! It's only left here for historical
- * reasons and because gdb uses it as a signature to notice
- * signal handler stack frames.
- */
- err |= __put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode);
+ put_user_try {
+ put_user_ex(sig, &frame->sig);
+ put_user_ex(&frame->info, &frame->pinfo);
+ put_user_ex(&frame->uc, &frame->puc);
+ err |= copy_siginfo_to_user(&frame->info, info);
+
+ /* Create the ucontext. */
+ if (cpu_has_xsave)
+ put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ put_user_ex(0, &frame->uc.uc_flags);
+ put_user_ex(0, &frame->uc.uc_link);
+ put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+ put_user_ex(sas_ss_flags(regs->sp),
+ &frame->uc.uc_stack.ss_flags);
+ put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
+ regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ /* Set up to return from userspace. */
+ restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
+ if (ka->sa.sa_flags & SA_RESTORER)
+ restorer = ka->sa.sa_restorer;
+ put_user_ex(restorer, &frame->pretcode);
+
+ /*
+ * This is movl $__NR_rt_sigreturn, %ax ; int $0x80
+ *
+ * WE DO NOT USE IT ANY MORE! It's only left here for historical
+ * reasons and because gdb uses it as a signature to notice
+ * signal handler stack frames.
+ */
+ put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode);
+ } put_user_catch(err);
if (err)
return -EFAULT;
return -EFAULT;
}
- /* Create the ucontext. */
- if (cpu_has_xsave)
- err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
- else
- err |= __put_user(0, &frame->uc.uc_flags);
- err |= __put_user(0, &frame->uc.uc_link);
- err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
- err |= __put_user(sas_ss_flags(regs->sp),
- &frame->uc.uc_stack.ss_flags);
- err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
-
- /* Set up to return from userspace. If provided, use a stub
- already in userspace. */
- /* x86-64 should always use SA_RESTORER. */
- if (ka->sa.sa_flags & SA_RESTORER) {
- err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
- } else {
- /* could use a vstub here */
- return -EFAULT;
- }
+ put_user_try {
+ /* Create the ucontext. */
+ if (cpu_has_xsave)
+ put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ put_user_ex(0, &frame->uc.uc_flags);
+ put_user_ex(0, &frame->uc.uc_link);
+ put_user_ex(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+ put_user_ex(sas_ss_flags(regs->sp),
+ &frame->uc.uc_stack.ss_flags);
+ put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ /* x86-64 should always use SA_RESTORER. */
+ if (ka->sa.sa_flags & SA_RESTORER) {
+ put_user_ex(ka->sa.sa_restorer, &frame->pretcode);
+ } else {
+ /* could use a vstub here */
+ err |= -EFAULT;
+ }
+ } put_user_catch(err);
if (err)
return -EFAULT;
struct old_sigaction __user *oact)
{
struct k_sigaction new_ka, old_ka;
- int ret;
+ int ret = 0;
if (act) {
old_sigset_t mask;
- if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
- __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
- __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)))
return -EFAULT;
- __get_user(new_ka.sa.sa_flags, &act->sa_flags);
- __get_user(mask, &act->sa_mask);
+ get_user_try {
+ get_user_ex(new_ka.sa.sa_handler, &act->sa_handler);
+ get_user_ex(new_ka.sa.sa_flags, &act->sa_flags);
+ get_user_ex(mask, &act->sa_mask);
+ get_user_ex(new_ka.sa.sa_restorer, &act->sa_restorer);
+ } get_user_catch(ret);
+
+ if (ret)
+ return -EFAULT;
siginitset(&new_ka.sa.sa_mask, mask);
}
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
if (!ret && oact) {
- if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
- __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
- __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
return -EFAULT;
- __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
- __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
+ put_user_try {
+ put_user_ex(old_ka.sa.sa_handler, &oact->sa_handler);
+ put_user_ex(old_ka.sa.sa_flags, &oact->sa_flags);
+ put_user_ex(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
+ put_user_ex(old_ka.sa.sa_restorer, &oact->sa_restorer);
+ } put_user_catch(ret);
+
+ if (ret)
+ return -EFAULT;
}
return ret;
}
#ifdef CONFIG_X86_32
-asmlinkage int sys_rt_sigreturn(struct pt_regs regs)
+/*
+ * Note: do not pass in pt_regs directly as with tail-call optimization
+ * GCC will incorrectly stomp on the caller's frame and corrupt user-space
+ * register state:
+ */
+asmlinkage int sys_rt_sigreturn(unsigned long __unused)
{
- return do_rt_sigreturn(®s);
+ struct pt_regs *regs = (struct pt_regs *)&__unused;
+
+ return do_rt_sigreturn(regs);
}
#else /* !CONFIG_X86_32 */
asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
projects / mv-sheeva.git / commitdiff