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-rw-r--r--arch/arm/Makefile2
-rw-r--r--arch/arm/include/asm/tlb.h105
-rw-r--r--arch/arm/include/asm/tlbflush.h7
-rw-r--r--arch/arm/kernel/kprobes-decode.c2
-rw-r--r--arch/arm/kernel/signal.c4
-rw-r--r--arch/arm/kernel/vmlinux.lds.S11
6 files changed, 109 insertions, 22 deletions
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index c22c1adfedd..6f7b29294c8 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -15,7 +15,7 @@ ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
LDFLAGS_vmlinux += --be8
endif
-OBJCOPYFLAGS :=-O binary -R .note -R .note.gnu.build-id -R .comment -S
+OBJCOPYFLAGS :=-O binary -R .comment -S
GZFLAGS :=-9
#KBUILD_CFLAGS +=-pipe
# Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:
diff --git a/arch/arm/include/asm/tlb.h b/arch/arm/include/asm/tlb.h
index f41a6f57cd1..82dfe5d0c41 100644
--- a/arch/arm/include/asm/tlb.h
+++ b/arch/arm/include/asm/tlb.h
@@ -18,16 +18,34 @@
#define __ASMARM_TLB_H
#include <asm/cacheflush.h>
-#include <asm/tlbflush.h>
#ifndef CONFIG_MMU
#include <linux/pagemap.h>
+
+#define tlb_flush(tlb) ((void) tlb)
+
#include <asm-generic/tlb.h>
#else /* !CONFIG_MMU */
+#include <linux/swap.h>
#include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
+
+/*
+ * We need to delay page freeing for SMP as other CPUs can access pages
+ * which have been removed but not yet had their TLB entries invalidated.
+ * Also, as ARMv7 speculative prefetch can drag new entries into the TLB,
+ * we need to apply this same delaying tactic to ensure correct operation.
+ */
+#if defined(CONFIG_SMP) || defined(CONFIG_CPU_32v7)
+#define tlb_fast_mode(tlb) 0
+#define FREE_PTE_NR 500
+#else
+#define tlb_fast_mode(tlb) 1
+#define FREE_PTE_NR 0
+#endif
/*
* TLB handling. This allows us to remove pages from the page
@@ -36,12 +54,58 @@
struct mmu_gather {
struct mm_struct *mm;
unsigned int fullmm;
+ struct vm_area_struct *vma;
unsigned long range_start;
unsigned long range_end;
+ unsigned int nr;
+ struct page *pages[FREE_PTE_NR];
};
DECLARE_PER_CPU(struct mmu_gather, mmu_gathers);
+/*
+ * This is unnecessarily complex. There's three ways the TLB shootdown
+ * code is used:
+ * 1. Unmapping a range of vmas. See zap_page_range(), unmap_region().
+ * tlb->fullmm = 0, and tlb_start_vma/tlb_end_vma will be called.
+ * tlb->vma will be non-NULL.
+ * 2. Unmapping all vmas. See exit_mmap().
+ * tlb->fullmm = 1, and tlb_start_vma/tlb_end_vma will be called.
+ * tlb->vma will be non-NULL. Additionally, page tables will be freed.
+ * 3. Unmapping argument pages. See shift_arg_pages().
+ * tlb->fullmm = 0, but tlb_start_vma/tlb_end_vma will not be called.
+ * tlb->vma will be NULL.
+ */
+static inline void tlb_flush(struct mmu_gather *tlb)
+{
+ if (tlb->fullmm || !tlb->vma)
+ flush_tlb_mm(tlb->mm);
+ else if (tlb->range_end > 0) {
+ flush_tlb_range(tlb->vma, tlb->range_start, tlb->range_end);
+ tlb->range_start = TASK_SIZE;
+ tlb->range_end = 0;
+ }
+}
+
+static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr)
+{
+ if (!tlb->fullmm) {
+ if (addr < tlb->range_start)
+ tlb->range_start = addr;
+ if (addr + PAGE_SIZE > tlb->range_end)
+ tlb->range_end = addr + PAGE_SIZE;
+ }
+}
+
+static inline void tlb_flush_mmu(struct mmu_gather *tlb)
+{
+ tlb_flush(tlb);
+ if (!tlb_fast_mode(tlb)) {
+ free_pages_and_swap_cache(tlb->pages, tlb->nr);
+ tlb->nr = 0;
+ }
+}
+
static inline struct mmu_gather *
tlb_gather_mmu(struct mm_struct *mm, unsigned int full_mm_flush)
{
@@ -49,6 +113,8 @@ tlb_gather_mmu(struct mm_struct *mm, unsigned int full_mm_flush)
tlb->mm = mm;
tlb->fullmm = full_mm_flush;
+ tlb->vma = NULL;
+ tlb->nr = 0;
return tlb;
}
@@ -56,8 +122,7 @@ tlb_gather_mmu(struct mm_struct *mm, unsigned int full_mm_flush)
static inline void
tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
{
- if (tlb->fullmm)
- flush_tlb_mm(tlb->mm);
+ tlb_flush_mmu(tlb);
/* keep the page table cache within bounds */
check_pgt_cache();
@@ -71,12 +136,7 @@ tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
static inline void
tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long addr)
{
- if (!tlb->fullmm) {
- if (addr < tlb->range_start)
- tlb->range_start = addr;
- if (addr + PAGE_SIZE > tlb->range_end)
- tlb->range_end = addr + PAGE_SIZE;
- }
+ tlb_add_flush(tlb, addr);
}
/*
@@ -89,6 +149,7 @@ tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
{
if (!tlb->fullmm) {
flush_cache_range(vma, vma->vm_start, vma->vm_end);
+ tlb->vma = vma;
tlb->range_start = TASK_SIZE;
tlb->range_end = 0;
}
@@ -97,12 +158,30 @@ tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
static inline void
tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
{
- if (!tlb->fullmm && tlb->range_end > 0)
- flush_tlb_range(vma, tlb->range_start, tlb->range_end);
+ if (!tlb->fullmm)
+ tlb_flush(tlb);
+}
+
+static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
+{
+ if (tlb_fast_mode(tlb)) {
+ free_page_and_swap_cache(page);
+ } else {
+ tlb->pages[tlb->nr++] = page;
+ if (tlb->nr >= FREE_PTE_NR)
+ tlb_flush_mmu(tlb);
+ }
+}
+
+static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
+ unsigned long addr)
+{
+ pgtable_page_dtor(pte);
+ tlb_add_flush(tlb, addr);
+ tlb_remove_page(tlb, pte);
}
-#define tlb_remove_page(tlb,page) free_page_and_swap_cache(page)
-#define pte_free_tlb(tlb, ptep, addr) pte_free((tlb)->mm, ptep)
+#define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr)
#define pmd_free_tlb(tlb, pmdp, addr) pmd_free((tlb)->mm, pmdp)
#define tlb_migrate_finish(mm) do { } while (0)
diff --git a/arch/arm/include/asm/tlbflush.h b/arch/arm/include/asm/tlbflush.h
index ce7378ea15a..d2005de383b 100644
--- a/arch/arm/include/asm/tlbflush.h
+++ b/arch/arm/include/asm/tlbflush.h
@@ -10,12 +10,7 @@
#ifndef _ASMARM_TLBFLUSH_H
#define _ASMARM_TLBFLUSH_H
-
-#ifndef CONFIG_MMU
-
-#define tlb_flush(tlb) ((void) tlb)
-
-#else /* CONFIG_MMU */
+#ifdef CONFIG_MMU
#include <asm/glue.h>
diff --git a/arch/arm/kernel/kprobes-decode.c b/arch/arm/kernel/kprobes-decode.c
index 2c1f0050c9c..8f6ed43861f 100644
--- a/arch/arm/kernel/kprobes-decode.c
+++ b/arch/arm/kernel/kprobes-decode.c
@@ -1437,7 +1437,7 @@ arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
return space_cccc_1100_010x(insn, asi);
- } else if ((insn & 0x0e000000) == 0x0c400000) {
+ } else if ((insn & 0x0e000000) == 0x0c000000) {
return space_cccc_110x(insn, asi);
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 907d5a620bc..abaf8445ce2 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -474,7 +474,9 @@ setup_return(struct pt_regs *regs, struct k_sigaction *ka,
unsigned long handler = (unsigned long)ka->sa.sa_handler;
unsigned long retcode;
int thumb = 0;
- unsigned long cpsr = regs->ARM_cpsr & ~PSR_f;
+ unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT);
+
+ cpsr |= PSR_ENDSTATE;
/*
* Maybe we need to deliver a 32-bit signal to a 26-bit task.
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 86b66f3f203..61462790757 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -21,6 +21,12 @@
#define ARM_CPU_KEEP(x)
#endif
+#if defined(CONFIG_SMP_ON_UP) && !defined(CONFIG_DEBUG_SPINLOCK)
+#define ARM_EXIT_KEEP(x) x
+#else
+#define ARM_EXIT_KEEP(x)
+#endif
+
OUTPUT_ARCH(arm)
ENTRY(stext)
@@ -43,6 +49,7 @@ SECTIONS
_sinittext = .;
HEAD_TEXT
INIT_TEXT
+ ARM_EXIT_KEEP(EXIT_TEXT)
_einittext = .;
ARM_CPU_DISCARD(PROC_INFO)
__arch_info_begin = .;
@@ -67,6 +74,7 @@ SECTIONS
#ifndef CONFIG_XIP_KERNEL
__init_begin = _stext;
INIT_DATA
+ ARM_EXIT_KEEP(EXIT_DATA)
#endif
}
@@ -162,6 +170,7 @@ SECTIONS
. = ALIGN(PAGE_SIZE);
__init_begin = .;
INIT_DATA
+ ARM_EXIT_KEEP(EXIT_DATA)
. = ALIGN(PAGE_SIZE);
__init_end = .;
#endif
@@ -247,6 +256,8 @@ SECTIONS
}
#endif
+ NOTES
+
BSS_SECTION(0, 0, 0)
_end = .;
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-11 18:52:27 +0000