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-rw-r--r--arch/arm/mm/context.c38
-rw-r--r--arch/arm/mm/init.c92
-rw-r--r--arch/arm/mm/proc-v7.S4
3 files changed, 90 insertions, 44 deletions
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index 845769e41332..c8c8b9ed02e0 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -165,13 +165,28 @@ static void flush_context(unsigned int cpu)
__flush_icache_all();
}
-static int is_reserved_asid(u64 asid)
+static bool check_update_reserved_asid(u64 asid, u64 newasid)
{
int cpu;
- for_each_possible_cpu(cpu)
- if (per_cpu(reserved_asids, cpu) == asid)
- return 1;
- return 0;
+ bool hit = false;
+
+ /*
+ * Iterate over the set of reserved ASIDs looking for a match.
+ * If we find one, then we can update our mm to use newasid
+ * (i.e. the same ASID in the current generation) but we can't
+ * exit the loop early, since we need to ensure that all copies
+ * of the old ASID are updated to reflect the mm. Failure to do
+ * so could result in us missing the reserved ASID in a future
+ * generation.
+ */
+ for_each_possible_cpu(cpu) {
+ if (per_cpu(reserved_asids, cpu) == asid) {
+ hit = true;
+ per_cpu(reserved_asids, cpu) = newasid;
+ }
+ }
+
+ return hit;
}
static u64 new_context(struct mm_struct *mm, unsigned int cpu)
@@ -181,12 +196,14 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
u64 generation = atomic64_read(&asid_generation);
if (asid != 0) {
+ u64 newasid = generation | (asid & ~ASID_MASK);
+
/*
* If our current ASID was active during a rollover, we
* can continue to use it and this was just a false alarm.
*/
- if (is_reserved_asid(asid))
- return generation | (asid & ~ASID_MASK);
+ if (check_update_reserved_asid(asid, newasid))
+ return newasid;
/*
* We had a valid ASID in a previous life, so try to re-use
@@ -194,7 +211,7 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
*/
asid &= ~ASID_MASK;
if (!__test_and_set_bit(asid, asid_map))
- goto bump_gen;
+ return newasid;
}
/*
@@ -216,11 +233,8 @@ static u64 new_context(struct mm_struct *mm, unsigned int cpu)
__set_bit(asid, asid_map);
cur_idx = asid;
-
-bump_gen:
- asid |= generation;
cpumask_clear(mm_cpumask(mm));
- return asid;
+ return asid | generation;
}
void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk)
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 8a63b4cdc0f2..7f8cd1b3557f 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -22,6 +22,7 @@
#include <linux/memblock.h>
#include <linux/dma-contiguous.h>
#include <linux/sizes.h>
+#include <linux/stop_machine.h>
#include <asm/cp15.h>
#include <asm/mach-types.h>
@@ -627,12 +628,10 @@ static struct section_perm ro_perms[] = {
* safe to be called with preemption disabled, as under stop_machine().
*/
static inline void section_update(unsigned long addr, pmdval_t mask,
- pmdval_t prot)
+ pmdval_t prot, struct mm_struct *mm)
{
- struct mm_struct *mm;
pmd_t *pmd;
- mm = current->active_mm;
pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
#ifdef CONFIG_ARM_LPAE
@@ -656,49 +655,82 @@ static inline bool arch_has_strict_perms(void)
return !!(get_cr() & CR_XP);
}
-#define set_section_perms(perms, field) { \
- size_t i; \
- unsigned long addr; \
- \
- if (!arch_has_strict_perms()) \
- return; \
- \
- for (i = 0; i < ARRAY_SIZE(perms); i++) { \
- if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) || \
- !IS_ALIGNED(perms[i].end, SECTION_SIZE)) { \
- pr_err("BUG: section %lx-%lx not aligned to %lx\n", \
- perms[i].start, perms[i].end, \
- SECTION_SIZE); \
- continue; \
- } \
- \
- for (addr = perms[i].start; \
- addr < perms[i].end; \
- addr += SECTION_SIZE) \
- section_update(addr, perms[i].mask, \
- perms[i].field); \
- } \
+void set_section_perms(struct section_perm *perms, int n, bool set,
+ struct mm_struct *mm)
+{
+ size_t i;
+ unsigned long addr;
+
+ if (!arch_has_strict_perms())
+ return;
+
+ for (i = 0; i < n; i++) {
+ if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
+ !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
+ pr_err("BUG: section %lx-%lx not aligned to %lx\n",
+ perms[i].start, perms[i].end,
+ SECTION_SIZE);
+ continue;
+ }
+
+ for (addr = perms[i].start;
+ addr < perms[i].end;
+ addr += SECTION_SIZE)
+ section_update(addr, perms[i].mask,
+ set ? perms[i].prot : perms[i].clear, mm);
+ }
+
}
-static inline void fix_kernmem_perms(void)
+static void update_sections_early(struct section_perm perms[], int n)
{
- set_section_perms(nx_perms, prot);
+ struct task_struct *t, *s;
+
+ read_lock(&tasklist_lock);
+ for_each_process(t) {
+ if (t->flags & PF_KTHREAD)
+ continue;
+ for_each_thread(t, s)
+ set_section_perms(perms, n, true, s->mm);
+ }
+ read_unlock(&tasklist_lock);
+ set_section_perms(perms, n, true, current->active_mm);
+ set_section_perms(perms, n, true, &init_mm);
+}
+
+int __fix_kernmem_perms(void *unused)
+{
+ update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
+ return 0;
+}
+
+void fix_kernmem_perms(void)
+{
+ stop_machine(__fix_kernmem_perms, NULL, NULL);
}
#ifdef CONFIG_DEBUG_RODATA
+int __mark_rodata_ro(void *unused)
+{
+ update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
+ return 0;
+}
+
void mark_rodata_ro(void)
{
- set_section_perms(ro_perms, prot);
+ stop_machine(__mark_rodata_ro, NULL, NULL);
}
void set_kernel_text_rw(void)
{
- set_section_perms(ro_perms, clear);
+ set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
+ current->active_mm);
}
void set_kernel_text_ro(void)
{
- set_section_perms(ro_perms, prot);
+ set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
+ current->active_mm);
}
#endif /* CONFIG_DEBUG_RODATA */
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index de2b246fed38..8e1ea433c3f1 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -95,7 +95,7 @@ ENDPROC(cpu_v7_dcache_clean_area)
.equ cpu_v7_suspend_size, 4 * 9
#ifdef CONFIG_ARM_CPU_SUSPEND
ENTRY(cpu_v7_do_suspend)
- stmfd sp!, {r4 - r10, lr}
+ stmfd sp!, {r4 - r11, lr}
mrc p15, 0, r4, c13, c0, 0 @ FCSE/PID
mrc p15, 0, r5, c13, c0, 3 @ User r/o thread ID
stmia r0!, {r4 - r5}
@@ -112,7 +112,7 @@ ENTRY(cpu_v7_do_suspend)
mrc p15, 0, r9, c1, c0, 1 @ Auxiliary control register
mrc p15, 0, r10, c1, c0, 2 @ Co-processor access control
stmia r0, {r5 - r11}
- ldmfd sp!, {r4 - r10, pc}
+ ldmfd sp!, {r4 - r11, pc}
ENDPROC(cpu_v7_do_suspend)
ENTRY(cpu_v7_do_resume)
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-24 23:16:48 +0000