[PATCH v3 22/23] powerpc/vdso: Migrate native signals to generic vdso_base
From: Dmitry Safonov
Date: Fri Jun 11 2021 - 14:04:58 EST
Generic way to track the land vma area.
Stat speaks for itself.
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/book3s/32/mmu-hash.h | 1 -
arch/powerpc/include/asm/book3s/64/mmu.h | 1 -
arch/powerpc/include/asm/mmu_context.h | 9 ------
arch/powerpc/include/asm/nohash/32/mmu-40x.h | 1 -
arch/powerpc/include/asm/nohash/32/mmu-44x.h | 1 -
arch/powerpc/include/asm/nohash/32/mmu-8xx.h | 1 -
arch/powerpc/include/asm/nohash/mmu-book3e.h | 1 -
arch/powerpc/kernel/signal_32.c | 8 ++---
arch/powerpc/kernel/signal_64.c | 4 +--
arch/powerpc/kernel/vdso.c | 31 +------------------
arch/powerpc/perf/callchain_32.c | 8 ++---
arch/powerpc/perf/callchain_64.c | 4 +--
arch/x86/include/asm/mmu_context.h | 5 ---
include/asm-generic/mm_hooks.h | 9 ++----
mm/mmap.c | 7 -----
16 files changed, 16 insertions(+), 76 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index a9f842230ee4..21e58d145c82 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -145,6 +145,7 @@ config PPC
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VDSO_BASE
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_KEEP_MEMBLOCK
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index b85f8e114a9c..d5ee68f394d9 100644
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -90,7 +90,6 @@ struct hash_pte {
typedef struct {
unsigned long id;
- void __user *vdso;
} mm_context_t;
void update_bats(void);
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index eace8c3f7b0a..66bcc3ee3add 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -111,7 +111,6 @@ typedef struct {
struct hash_mm_context *hash_context;
- void __user *vdso;
/*
* pagetable fragment support
*/
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 4bc45d3ed8b0..71dedeac7fdb 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -260,15 +260,6 @@ static inline void enter_lazy_tlb(struct mm_struct *mm,
extern void arch_exit_mmap(struct mm_struct *mm);
-static inline void arch_unmap(struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
- unsigned long vdso_base = (unsigned long)mm->context.vdso;
-
- if (start <= vdso_base && vdso_base < end)
- mm->context.vdso = NULL;
-}
-
#ifdef CONFIG_PPC_MEM_KEYS
bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write,
bool execute, bool foreign);
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-40x.h b/arch/powerpc/include/asm/nohash/32/mmu-40x.h
index 8a8f13a22cf4..366088bb1c3f 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-40x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-40x.h
@@ -57,7 +57,6 @@
typedef struct {
unsigned int id;
unsigned int active;
- void __user *vdso;
} mm_context_t;
#endif /* !__ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-44x.h b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
index 2d92a39d8f2e..d67256ab7887 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-44x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
@@ -108,7 +108,6 @@ extern unsigned int tlb_44x_index;
typedef struct {
unsigned int id;
unsigned int active;
- void __user *vdso;
} mm_context_t;
/* patch sites */
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
index 6e4faa0a9b35..9e394810faac 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
@@ -184,7 +184,6 @@ void mmu_pin_tlb(unsigned long top, bool readonly);
typedef struct {
unsigned int id;
unsigned int active;
- void __user *vdso;
void *pte_frag;
} mm_context_t;
diff --git a/arch/powerpc/include/asm/nohash/mmu-book3e.h b/arch/powerpc/include/asm/nohash/mmu-book3e.h
index e43a418d3ccd..61ac19f315e5 100644
--- a/arch/powerpc/include/asm/nohash/mmu-book3e.h
+++ b/arch/powerpc/include/asm/nohash/mmu-book3e.h
@@ -238,7 +238,6 @@ extern unsigned int tlbcam_index;
typedef struct {
unsigned int id;
unsigned int active;
- void __user *vdso;
} mm_context_t;
/* Page size definitions, common between 32 and 64-bit
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 8f05ed0da292..ae61c480af53 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -824,8 +824,8 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
}
/* Save user registers on the stack */
- if (tsk->mm->context.vdso) {
- tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp_rt32);
+ if (tsk->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE) {
+ tramp = VDSO32_SYMBOL(tsk->mm->vdso_base, sigtramp_rt32);
} else {
tramp = (unsigned long)mctx->mc_pad;
/* Set up the sigreturn trampoline: li r0,sigret; sc */
@@ -922,8 +922,8 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
else
unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
- if (tsk->mm->context.vdso) {
- tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp32);
+ if (tsk->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE) {
+ tramp = VDSO32_SYMBOL(tsk->mm->vdso_base, sigtramp32);
} else {
tramp = (unsigned long)mctx->mc_pad;
/* Set up the sigreturn trampoline: li r0,sigret; sc */
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index dca66481d0c2..468866dc1e0e 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -906,8 +906,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
tsk->thread.fp_state.fpscr = 0;
/* Set up to return from userspace. */
- if (tsk->mm->context.vdso) {
- regs->nip = VDSO64_SYMBOL(tsk->mm->context.vdso, sigtramp_rt64);
+ if (tsk->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE) {
+ regs->nip = VDSO64_SYMBOL(tsk->mm->vdso_base, sigtramp_rt64);
} else {
err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
if (err)
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 6d6e575630c1..2080a0540537 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -57,29 +57,6 @@ enum vvar_pages {
VVAR_NR_PAGES,
};
-static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma,
- unsigned long text_size)
-{
- unsigned long new_size = new_vma->vm_end - new_vma->vm_start;
-
- if (new_size != text_size)
- return -EINVAL;
-
- current->mm->context.vdso = (void __user *)new_vma->vm_start;
-
- return 0;
-}
-
-static int vdso32_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma)
-{
- return vdso_mremap(sm, new_vma, &vdso32_end - &vdso32_start);
-}
-
-static int vdso64_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma)
-{
- return vdso_mremap(sm, new_vma, &vdso64_end - &vdso64_start);
-}
-
static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
struct vm_area_struct *vma, struct vm_fault *vmf);
@@ -90,12 +67,10 @@ static struct vm_special_mapping vvar_spec __ro_after_init = {
static struct vm_special_mapping vdso32_spec __ro_after_init = {
.name = "[vdso]",
- .mremap = vdso32_mremap,
};
static struct vm_special_mapping vdso64_spec __ro_after_init = {
.name = "[vdso]",
- .mremap = vdso64_mremap,
};
#ifdef CONFIG_TIME_NS
@@ -251,7 +226,7 @@ static int __arch_setup_additional_pages(unsigned long *sysinfo_ehdr)
if (IS_ERR(vma)) {
do_munmap(mm, vdso_base, vvar_size, NULL);
} else {
- mm->context.vdso = (void __user *)vdso_base + vvar_size;
+ mm->vdso_base = (void __user *)vdso_base + vvar_size;
*sysinfo_ehdr = vdso_base + vvar_size;
}
@@ -263,14 +238,10 @@ int arch_setup_additional_pages(unsigned long *sysinfo_ehdr)
struct mm_struct *mm = current->mm;
int rc;
- mm->context.vdso = NULL;
-
if (mmap_write_lock_killable(mm))
return -EINTR;
rc = __arch_setup_additional_pages(sysinfo_ehdr);
- if (rc)
- mm->context.vdso = NULL;
mmap_write_unlock(mm);
return rc;
diff --git a/arch/powerpc/perf/callchain_32.c b/arch/powerpc/perf/callchain_32.c
index b83c47b7947f..c48b63e16603 100644
--- a/arch/powerpc/perf/callchain_32.c
+++ b/arch/powerpc/perf/callchain_32.c
@@ -59,8 +59,8 @@ static int is_sigreturn_32_address(unsigned int nip, unsigned int fp)
{
if (nip == fp + offsetof(struct signal_frame_32, mctx.mc_pad))
return 1;
- if (current->mm->context.vdso &&
- nip == VDSO32_SYMBOL(current->mm->context.vdso, sigtramp32))
+ if (current->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE &&
+ nip == VDSO32_SYMBOL(current->mm->vdso_base, sigtramp32))
return 1;
return 0;
}
@@ -70,8 +70,8 @@ static int is_rt_sigreturn_32_address(unsigned int nip, unsigned int fp)
if (nip == fp + offsetof(struct rt_signal_frame_32,
uc.uc_mcontext.mc_pad))
return 1;
- if (current->mm->context.vdso &&
- nip == VDSO32_SYMBOL(current->mm->context.vdso, sigtramp_rt32))
+ if (current->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE &&
+ nip == VDSO32_SYMBOL(current->mm->vdso_base, sigtramp_rt32))
return 1;
return 0;
}
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c
index 8d0df4226328..ef7116bd525a 100644
--- a/arch/powerpc/perf/callchain_64.c
+++ b/arch/powerpc/perf/callchain_64.c
@@ -68,8 +68,8 @@ static int is_sigreturn_64_address(unsigned long nip, unsigned long fp)
{
if (nip == fp + offsetof(struct signal_frame_64, tramp))
return 1;
- if (current->mm->context.vdso &&
- nip == VDSO64_SYMBOL(current->mm->context.vdso, sigtramp_rt64))
+ if (current->mm->vdso_base != (void __user *)UNMAPPED_VDSO_BASE &&
+ nip == VDSO64_SYMBOL(current->mm->vdso_base, sigtramp_rt64))
return 1;
return 0;
}
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 27516046117a..394aeaf136bb 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -190,11 +190,6 @@ static inline bool is_64bit_mm(struct mm_struct *mm)
}
#endif
-static inline void arch_unmap(struct mm_struct *mm, unsigned long start,
- unsigned long end)
-{
-}
-
/*
* We only want to enforce protection keys on the current process
* because we effectively have no access to PKRU for other
diff --git a/include/asm-generic/mm_hooks.h b/include/asm-generic/mm_hooks.h
index 4dbb177d1150..6cd41034743d 100644
--- a/include/asm-generic/mm_hooks.h
+++ b/include/asm-generic/mm_hooks.h
@@ -1,7 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
- * Define generic no-op hooks for arch_dup_mmap, arch_exit_mmap
- * and arch_unmap to be included in asm-FOO/mmu_context.h for any
+ * Define generic no-op hooks for arch_dup_mmap() and arch_exit_mmap()
+ * to be included in asm-FOO/mmu_context.h for any
* arch FOO which doesn't need to hook these.
*/
#ifndef _ASM_GENERIC_MM_HOOKS_H
@@ -17,11 +17,6 @@ static inline void arch_exit_mmap(struct mm_struct *mm)
{
}
-static inline void arch_unmap(struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
-}
-
static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
bool write, bool execute, bool foreign)
{
diff --git a/mm/mmap.c b/mm/mmap.c
index 5d1ffce51119..d22eb9ab770c 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2821,13 +2821,6 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
if (len == 0)
return -EINVAL;
- /*
- * arch_unmap() might do unmaps itself. It must be called
- * and finish any rbtree manipulation before this code
- * runs and also starts to manipulate the rbtree.
- */
- arch_unmap(mm, start, end);
-
/* Find the first overlapping VMA */
vma = find_vma(mm, start);
if (!vma)
--
2.31.1