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-rw-r--r--lib/Kconfig.debug60
-rw-r--r--lib/div64.c2
-rw-r--r--lib/ioremap.c53
-rw-r--r--lib/iov_iter.c26
-rw-r--r--lib/kobject.c7
-rw-r--r--lib/lockref.c2
-rw-r--r--lib/lz4/lz4_decompress.c18
7 files changed, 144 insertions, 24 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c5cefb3c009c..17670573dda8 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -865,6 +865,19 @@ config SCHED_STACK_END_CHECK
data corruption or a sporadic crash at a later stage once the region
is examined. The runtime overhead introduced is minimal.
+config DEBUG_TIMEKEEPING
+ bool "Enable extra timekeeping sanity checking"
+ help
+ This option will enable additional timekeeping sanity checks
+ which may be helpful when diagnosing issues where timekeeping
+ problems are suspected.
+
+ This may include checks in the timekeeping hotpaths, so this
+ option may have a (very small) performance impact to some
+ workloads.
+
+ If unsure, say N.
+
config TIMER_STATS
bool "Collect kernel timers statistics"
depends on DEBUG_KERNEL && PROC_FS
@@ -1180,16 +1193,7 @@ config DEBUG_CREDENTIALS
menu "RCU Debugging"
config PROVE_RCU
- bool "RCU debugging: prove RCU correctness"
- depends on PROVE_LOCKING
- default n
- help
- This feature enables lockdep extensions that check for correct
- use of RCU APIs. This is currently under development. Say Y
- if you want to debug RCU usage or help work on the PROVE_RCU
- feature.
-
- Say N if you are unsure.
+ def_bool PROVE_LOCKING
config PROVE_RCU_REPEATEDLY
bool "RCU debugging: don't disable PROVE_RCU on first splat"
@@ -1257,6 +1261,30 @@ config RCU_TORTURE_TEST_RUNNABLE
Say N here if you want the RCU torture tests to start only
after being manually enabled via /proc.
+config RCU_TORTURE_TEST_SLOW_INIT
+ bool "Slow down RCU grace-period initialization to expose races"
+ depends on RCU_TORTURE_TEST
+ help
+ This option makes grace-period initialization block for a
+ few jiffies between initializing each pair of consecutive
+ rcu_node structures. This helps to expose races involving
+ grace-period initialization, in other words, it makes your
+ kernel less stable. It can also greatly increase grace-period
+ latency, especially on systems with large numbers of CPUs.
+ This is useful when torture-testing RCU, but in almost no
+ other circumstance.
+
+ Say Y here if you want your system to crash and hang more often.
+ Say N if you want a sane system.
+
+config RCU_TORTURE_TEST_SLOW_INIT_DELAY
+ int "How much to slow down RCU grace-period initialization"
+ range 0 5
+ default 3
+ help
+ This option specifies the number of jiffies to wait between
+ each rcu_node structure initialization.
+
config RCU_CPU_STALL_TIMEOUT
int "RCU CPU stall timeout in seconds"
depends on RCU_STALL_COMMON
@@ -1732,6 +1760,18 @@ config TEST_UDELAY
If unsure, say N.
+config MEMTEST
+ bool "Memtest"
+ depends on HAVE_MEMBLOCK
+ ---help---
+ This option adds a kernel parameter 'memtest', which allows memtest
+ to be set.
+ memtest=0, mean disabled; -- default
+ memtest=1, mean do 1 test pattern;
+ ...
+ memtest=17, mean do 17 test patterns.
+ If you are unsure how to answer this question, answer N.
+
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
diff --git a/lib/div64.c b/lib/div64.c
index 4382ad77777e..19ea7ed4b948 100644
--- a/lib/div64.c
+++ b/lib/div64.c
@@ -127,7 +127,7 @@ EXPORT_SYMBOL(div64_u64_rem);
* by the book 'Hacker's Delight'. The original source and full proof
* can be found here and is available for use without restriction.
*
- * 'http://www.hackersdelight.org/HDcode/newCode/divDouble.c.txt'
+ * 'http://www.hackersdelight.org/hdcodetxt/divDouble.c.txt'
*/
#ifndef div64_u64
u64 div64_u64(u64 dividend, u64 divisor)
diff --git a/lib/ioremap.c b/lib/ioremap.c
index 0c9216c48762..86c8911b0e3a 100644
--- a/lib/ioremap.c
+++ b/lib/ioremap.c
@@ -13,6 +13,43 @@
#include <asm/cacheflush.h>
#include <asm/pgtable.h>
+#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
+static int __read_mostly ioremap_pud_capable;
+static int __read_mostly ioremap_pmd_capable;
+static int __read_mostly ioremap_huge_disabled;
+
+static int __init set_nohugeiomap(char *str)
+{
+ ioremap_huge_disabled = 1;
+ return 0;
+}
+early_param("nohugeiomap", set_nohugeiomap);
+
+void __init ioremap_huge_init(void)
+{
+ if (!ioremap_huge_disabled) {
+ if (arch_ioremap_pud_supported())
+ ioremap_pud_capable = 1;
+ if (arch_ioremap_pmd_supported())
+ ioremap_pmd_capable = 1;
+ }
+}
+
+static inline int ioremap_pud_enabled(void)
+{
+ return ioremap_pud_capable;
+}
+
+static inline int ioremap_pmd_enabled(void)
+{
+ return ioremap_pmd_capable;
+}
+
+#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
+static inline int ioremap_pud_enabled(void) { return 0; }
+static inline int ioremap_pmd_enabled(void) { return 0; }
+#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
+
static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
@@ -43,6 +80,14 @@ static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
return -ENOMEM;
do {
next = pmd_addr_end(addr, end);
+
+ if (ioremap_pmd_enabled() &&
+ ((next - addr) == PMD_SIZE) &&
+ IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {
+ if (pmd_set_huge(pmd, phys_addr + addr, prot))
+ continue;
+ }
+
if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
return -ENOMEM;
} while (pmd++, addr = next, addr != end);
@@ -61,6 +106,14 @@ static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
return -ENOMEM;
do {
next = pud_addr_end(addr, end);
+
+ if (ioremap_pud_enabled() &&
+ ((next - addr) == PUD_SIZE) &&
+ IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {
+ if (pud_set_huge(pud, phys_addr + addr, prot))
+ continue;
+ }
+
if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
return -ENOMEM;
} while (pud++, addr = next, addr != end);
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index fc6e33f6b7f3..75232ad0a5e7 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -317,6 +317,32 @@ int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes)
}
EXPORT_SYMBOL(iov_iter_fault_in_readable);
+/*
+ * Fault in one or more iovecs of the given iov_iter, to a maximum length of
+ * bytes. For each iovec, fault in each page that constitutes the iovec.
+ *
+ * Return 0 on success, or non-zero if the memory could not be accessed (i.e.
+ * because it is an invalid address).
+ */
+int iov_iter_fault_in_multipages_readable(struct iov_iter *i, size_t bytes)
+{
+ size_t skip = i->iov_offset;
+ const struct iovec *iov;
+ int err;
+ struct iovec v;
+
+ if (!(i->type & (ITER_BVEC|ITER_KVEC))) {
+ iterate_iovec(i, bytes, v, iov, skip, ({
+ err = fault_in_multipages_readable(v.iov_base,
+ v.iov_len);
+ if (unlikely(err))
+ return err;
+ 0;}))
+ }
+ return 0;
+}
+EXPORT_SYMBOL(iov_iter_fault_in_multipages_readable);
+
void iov_iter_init(struct iov_iter *i, int direction,
const struct iovec *iov, unsigned long nr_segs,
size_t count)
diff --git a/lib/kobject.c b/lib/kobject.c
index 03d4ab349fa7..3b841b97fccd 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -576,8 +576,13 @@ void kobject_del(struct kobject *kobj)
*/
struct kobject *kobject_get(struct kobject *kobj)
{
- if (kobj)
+ if (kobj) {
+ if (!kobj->state_initialized)
+ WARN(1, KERN_WARNING "kobject: '%s' (%p): is not "
+ "initialized, yet kobject_get() is being "
+ "called.\n", kobject_name(kobj), kobj);
kref_get(&kobj->kref);
+ }
return kobj;
}
diff --git a/lib/lockref.c b/lib/lockref.c
index ecb9a665ec19..494994bf17c8 100644
--- a/lib/lockref.c
+++ b/lib/lockref.c
@@ -18,7 +18,7 @@
#define CMPXCHG_LOOP(CODE, SUCCESS) do { \
struct lockref old; \
BUILD_BUG_ON(sizeof(old) != 8); \
- old.lock_count = ACCESS_ONCE(lockref->lock_count); \
+ old.lock_count = READ_ONCE(lockref->lock_count); \
while (likely(arch_spin_value_unlocked(old.lock.rlock.raw_lock))) { \
struct lockref new = old, prev = old; \
CODE \
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index f0f5c5c3de12..26cc6029b280 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -47,6 +47,11 @@
#include "lz4defs.h"
+static const int dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
+#if LZ4_ARCH64
+static const int dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
+#endif
+
static int lz4_uncompress(const char *source, char *dest, int osize)
{
const BYTE *ip = (const BYTE *) source;
@@ -56,10 +61,6 @@ static int lz4_uncompress(const char *source, char *dest, int osize)
BYTE *cpy;
unsigned token;
size_t length;
- size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
-#if LZ4_ARCH64
- size_t dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
-#endif
while (1) {
@@ -116,7 +117,7 @@ static int lz4_uncompress(const char *source, char *dest, int osize)
/* copy repeated sequence */
if (unlikely((op - ref) < STEPSIZE)) {
#if LZ4_ARCH64
- size_t dec64 = dec64table[op - ref];
+ int dec64 = dec64table[op - ref];
#else
const int dec64 = 0;
#endif
@@ -177,11 +178,6 @@ static int lz4_uncompress_unknownoutputsize(const char *source, char *dest,
BYTE * const oend = op + maxoutputsize;
BYTE *cpy;
- size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0};
-#if LZ4_ARCH64
- size_t dec64table[] = {0, 0, 0, -1, 0, 1, 2, 3};
-#endif
-
/* Main Loop */
while (ip < iend) {
@@ -249,7 +245,7 @@ static int lz4_uncompress_unknownoutputsize(const char *source, char *dest,
/* copy repeated sequence */
if (unlikely((op - ref) < STEPSIZE)) {
#if LZ4_ARCH64
- size_t dec64 = dec64table[op - ref];
+ int dec64 = dec64table[op - ref];
#else
const int dec64 = 0;
#endif