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-rw-r--r--lib/Kconfig.debug23
-rw-r--r--lib/extable.c50
-rw-r--r--lib/strncpy_from_user.c17
-rw-r--r--lib/strnlen_user.c21
4 files changed, 90 insertions, 21 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 8c15b29d5adc..63d14d9b51d8 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -707,15 +707,27 @@ config LOCKUP_DETECTOR
The overhead should be minimal. A periodic hrtimer runs to
generate interrupts and kick the watchdog task every 4 seconds.
An NMI is generated every 10 seconds or so to check for hardlockups.
+ If NMIs are not available on the platform, every 12 seconds the
+ hrtimer interrupt on one cpu will be used to check for hardlockups
+ on the next cpu.
The frequency of hrtimer and NMI events and the soft and hard lockup
thresholds can be controlled through the sysctl watchdog_thresh.
-config HARDLOCKUP_DETECTOR
+config HARDLOCKUP_DETECTOR_NMI
def_bool y
depends on LOCKUP_DETECTOR && !HAVE_NMI_WATCHDOG
depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI
+config HARDLOCKUP_DETECTOR_OTHER_CPU
+ def_bool y
+ depends on LOCKUP_DETECTOR && SMP
+ depends on !HARDLOCKUP_DETECTOR_NMI && !HAVE_NMI_WATCHDOG
+
+config HARDLOCKUP_DETECTOR
+ def_bool y
+ depends on HARDLOCKUP_DETECTOR_NMI || HARDLOCKUP_DETECTOR_OTHER_CPU
+
config BOOTPARAM_HARDLOCKUP_PANIC
bool "Panic (Reboot) On Hard Lockups"
depends on HARDLOCKUP_DETECTOR
@@ -855,6 +867,15 @@ config SCHED_INFO
bool
default n
+config PANIC_ON_RT_THROTTLING
+ bool "Panic on RT throttling"
+ help
+ Say Y here to enable the kernel to panic when a realtime
+ runqueue is throttled. This may be useful for detecting
+ and debugging RT throttling issues.
+
+ Say N if unsure.
+
config SCHEDSTATS
bool "Collect scheduler statistics"
depends on DEBUG_KERNEL && PROC_FS
diff --git a/lib/extable.c b/lib/extable.c
index 4cac81ec225e..0be02ad561e9 100644
--- a/lib/extable.c
+++ b/lib/extable.c
@@ -14,7 +14,37 @@
#include <linux/sort.h>
#include <asm/uaccess.h>
+#ifndef ARCH_HAS_RELATIVE_EXTABLE
+#define ex_to_insn(x) ((x)->insn)
+#else
+static inline unsigned long ex_to_insn(const struct exception_table_entry *x)
+{
+ return (unsigned long)&x->insn + x->insn;
+}
+#endif
+
#ifndef ARCH_HAS_SORT_EXTABLE
+#ifndef ARCH_HAS_RELATIVE_EXTABLE
+#define swap_ex NULL
+#else
+static void swap_ex(void *a, void *b, int size)
+{
+ struct exception_table_entry *x = a, *y = b, tmp;
+ int delta = b - a;
+
+ tmp = *x;
+ x->insn = y->insn + delta;
+ y->insn = tmp.insn - delta;
+
+#ifdef swap_ex_entry_fixup
+ swap_ex_entry_fixup(x, y, tmp, delta);
+#else
+ x->fixup = y->fixup + delta;
+ y->fixup = tmp.fixup - delta;
+#endif
+}
+#endif /* ARCH_HAS_RELATIVE_EXTABLE */
+
/*
* The exception table needs to be sorted so that the binary
* search that we use to find entries in it works properly.
@@ -26,9 +56,9 @@ static int cmp_ex(const void *a, const void *b)
const struct exception_table_entry *x = a, *y = b;
/* avoid overflow */
- if (x->insn > y->insn)
+ if (ex_to_insn(x) > ex_to_insn(y))
return 1;
- if (x->insn < y->insn)
+ if (ex_to_insn(x) < ex_to_insn(y))
return -1;
return 0;
}
@@ -37,7 +67,7 @@ void sort_extable(struct exception_table_entry *start,
struct exception_table_entry *finish)
{
sort(start, finish - start, sizeof(struct exception_table_entry),
- cmp_ex, NULL);
+ cmp_ex, swap_ex);
}
#ifdef CONFIG_MODULES
@@ -48,13 +78,15 @@ void sort_extable(struct exception_table_entry *start,
void trim_init_extable(struct module *m)
{
/*trim the beginning*/
- while (m->num_exentries && within_module_init(m->extable[0].insn, m)) {
+ while (m->num_exentries &&
+ within_module_init(ex_to_insn(&m->extable[0]), m)) {
m->extable++;
m->num_exentries--;
}
/*trim the end*/
while (m->num_exentries &&
- within_module_init(m->extable[m->num_exentries-1].insn, m))
+ within_module_init(ex_to_insn(&m->extable[m->num_exentries - 1]),
+ m))
m->num_exentries--;
}
#endif /* CONFIG_MODULES */
@@ -81,13 +113,13 @@ search_extable(const struct exception_table_entry *first,
* careful, the distance between value and insn
* can be larger than MAX_LONG:
*/
- if (mid->insn < value)
+ if (ex_to_insn(mid) < value)
first = mid + 1;
- else if (mid->insn > value)
+ else if (ex_to_insn(mid) > value)
last = mid - 1;
else
return mid;
- }
- return NULL;
+ }
+ return NULL;
}
#endif
diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c
index e0af6ff73d14..05efc1fa97f0 100644
--- a/lib/strncpy_from_user.c
+++ b/lib/strncpy_from_user.c
@@ -1,5 +1,6 @@
#include <linux/compiler.h>
#include <linux/export.h>
+#include <linux/thread_info.h>
#include <linux/uaccess.h>
#include <linux/kernel.h>
#include <linux/errno.h>
@@ -39,8 +40,8 @@ static inline long do_strncpy_from_user(char *dst, const char __user *src, long
unsigned long c, data;
/* Fall back to byte-at-a-time if we get a page fault */
- if (unlikely(__get_user(c,(unsigned long __user *)(src+res))))
- break;
+ unsafe_get_user(c, (unsigned long __user *)(src+res), byte_at_a_time);
+
*(unsigned long *)(dst+res) = c;
if (has_zero(c, &data, &constants)) {
data = prep_zero_mask(c, data, &constants);
@@ -55,8 +56,7 @@ byte_at_a_time:
while (max) {
char c;
- if (unlikely(__get_user(c,src+res)))
- return -EFAULT;
+ unsafe_get_user(c,src+res, efault);
dst[res] = c;
if (!c)
return res;
@@ -75,6 +75,7 @@ byte_at_a_time:
* Nope: we hit the address space limit, and we still had more
* characters the caller would have wanted. That's an EFAULT.
*/
+efault:
return -EFAULT;
}
@@ -107,7 +108,13 @@ long strncpy_from_user(char *dst, const char __user *src, long count)
src_addr = (unsigned long)src;
if (likely(src_addr < max_addr)) {
unsigned long max = max_addr - src_addr;
- return do_strncpy_from_user(dst, src, count, max);
+ long retval;
+
+ check_object_size(dst, count, false);
+ user_access_begin();
+ retval = do_strncpy_from_user(dst, src, count, max);
+ user_access_end();
+ return retval;
}
return -EFAULT;
}
diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c
index 3a5f2b366d84..8e105ed4df12 100644
--- a/lib/strnlen_user.c
+++ b/lib/strnlen_user.c
@@ -45,8 +45,7 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count,
src -= align;
max += align;
- if (unlikely(__get_user(c,(unsigned long __user *)src)))
- return 0;
+ unsafe_get_user(c, (unsigned long __user *)src, efault);
c |= aligned_byte_mask(align);
for (;;) {
@@ -61,8 +60,7 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count,
if (unlikely(max <= sizeof(unsigned long)))
break;
max -= sizeof(unsigned long);
- if (unlikely(__get_user(c,(unsigned long __user *)(src+res))))
- return 0;
+ unsafe_get_user(c, (unsigned long __user *)(src+res), efault);
}
res -= align;
@@ -77,6 +75,7 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count,
* Nope: we hit the address space limit, and we still had more
* characters the caller would have wanted. That's 0.
*/
+efault:
return 0;
}
@@ -112,7 +111,12 @@ long strnlen_user(const char __user *str, long count)
src_addr = (unsigned long)str;
if (likely(src_addr < max_addr)) {
unsigned long max = max_addr - src_addr;
- return do_strnlen_user(str, count, max);
+ long retval;
+
+ user_access_begin();
+ retval = do_strnlen_user(str, count, max);
+ user_access_end();
+ return retval;
}
return 0;
}
@@ -141,7 +145,12 @@ long strlen_user(const char __user *str)
src_addr = (unsigned long)str;
if (likely(src_addr < max_addr)) {
unsigned long max = max_addr - src_addr;
- return do_strnlen_user(str, ~0ul, max);
+ long retval;
+
+ user_access_begin();
+ retval = do_strnlen_user(str, ~0ul, max);
+ user_access_end();
+ return retval;
}
return 0;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-22 23:34:47 +0000