From 697f8d0348a652593d195a13dd1067d9df911a82 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Wed, 30 Jul 2008 16:29:19 -0700 Subject: random32: seeding improvement The rationale is: * use u32 consistently * no need to do LCG on values from (better) get_random_bytes * use more data from get_random_bytes for secondary seeding * don't reduce state space on srandom32() * enforce state variable initialization restrictions Note: the second paper has a version of random32() with even longer period and a version of random64() if needed. Signed-off-by: Stephen Hemminger Signed-off-by: Andrew Morton --- lib/random32.c | 48 +++++++++++++++++++++++++++--------------------- 1 file changed, 27 insertions(+), 21 deletions(-) (limited to 'lib') diff --git a/lib/random32.c b/lib/random32.c index ca87d86992bd..217d5c4b666d 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -56,23 +56,12 @@ static u32 __random32(struct rnd_state *state) return (state->s1 ^ state->s2 ^ state->s3); } -static void __set_random32(struct rnd_state *state, unsigned long s) +/* + * Handle minimum values for seeds + */ +static inline u32 __seed(u32 x, u32 m) { - if (s == 0) - s = 1; /* default seed is 1 */ - -#define LCG(n) (69069 * n) - state->s1 = LCG(s); - state->s2 = LCG(state->s1); - state->s3 = LCG(state->s2); - - /* "warm it up" */ - __random32(state); - __random32(state); - __random32(state); - __random32(state); - __random32(state); - __random32(state); + return (x < m) ? x + m : x; } /** @@ -107,7 +96,7 @@ void srandom32(u32 entropy) */ for_each_possible_cpu (i) { struct rnd_state *state = &per_cpu(net_rand_state, i); - __set_random32(state, state->s1 ^ entropy); + state->s1 = __seed(state->s1 ^ entropy, 1); } } EXPORT_SYMBOL(srandom32); @@ -122,7 +111,19 @@ static int __init random32_init(void) for_each_possible_cpu(i) { struct rnd_state *state = &per_cpu(net_rand_state,i); - __set_random32(state, i + jiffies); + +#define LCG(x) ((x) * 69069) /* super-duper LCG */ + state->s1 = __seed(LCG(i + jiffies), 1); + state->s2 = __seed(LCG(state->s1), 7); + state->s3 = __seed(LCG(state->s2), 15); + + /* "warm it up" */ + __random32(state); + __random32(state); + __random32(state); + __random32(state); + __random32(state); + __random32(state); } return 0; } @@ -135,13 +136,18 @@ core_initcall(random32_init); static int __init random32_reseed(void) { int i; - unsigned long seed; for_each_possible_cpu(i) { struct rnd_state *state = &per_cpu(net_rand_state,i); + u32 seeds[3]; + + get_random_bytes(&seeds, sizeof(seeds)); + state->s1 = __seed(seeds[0], 1); + state->s2 = __seed(seeds[1], 7); + state->s3 = __seed(seeds[2], 15); - get_random_bytes(&seed, sizeof(seed)); - __set_random32(state, seed); + /* mix it in */ + __random32(state); } return 0; } -- cgit v1.2.2 From e0fdace10e75dac67d906213b780ff1b1a4cc360 Mon Sep 17 00:00:00 2001 From: David Miller Date: Fri, 1 Aug 2008 01:11:22 -0700 Subject: debug_locks: set oops_in_progress if we will log messages. Otherwise lock debugging messages on runqueue locks can deadlock the system due to the wakeups performed by printk(). Signed-off-by: David S. Miller Signed-off-by: Ingo Molnar --- lib/debug_locks.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'lib') diff --git a/lib/debug_locks.c b/lib/debug_locks.c index 0ef01d14727c..0218b4693dd8 100644 --- a/lib/debug_locks.c +++ b/lib/debug_locks.c @@ -8,6 +8,7 @@ * * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar */ +#include #include #include #include @@ -37,6 +38,7 @@ int debug_locks_off(void) { if (xchg(&debug_locks, 0)) { if (!debug_locks_silent) { + oops_in_progress = 1; console_verbose(); return 1; } -- cgit v1.2.2 From 5f5ddfb3605d2a4f555a7ff034859e623eafcd27 Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Fri, 1 Aug 2008 08:39:34 -0500 Subject: kgdb: remove the requirement for CONFIG_FRAME_POINTER There is no technical reason that the kgdb core requires frame pointers. It is up to the end user of KGDB to decide if they need them or not. [ anemo@mba.ocn.ne.jp: removed frame pointers on mips ] Signed-off-by: Jason Wessel --- lib/Kconfig.kgdb | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb index 2cfd2721f7ed..9b5d1d7f2ef7 100644 --- a/lib/Kconfig.kgdb +++ b/lib/Kconfig.kgdb @@ -4,14 +4,17 @@ config HAVE_ARCH_KGDB menuconfig KGDB bool "KGDB: kernel debugging with remote gdb" - select FRAME_POINTER depends on HAVE_ARCH_KGDB depends on DEBUG_KERNEL && EXPERIMENTAL help If you say Y here, it will be possible to remotely debug the - kernel using gdb. Documentation of kernel debugger is available - at http://kgdb.sourceforge.net as well as in DocBook form - in Documentation/DocBook/. If unsure, say N. + kernel using gdb. It is recommended but not required, that + you also turn on the kernel config option + CONFIG_FRAME_POINTER to aid in producing more reliable stack + backtraces in the external debugger. Documentation of + kernel debugger is available at http://kgdb.sourceforge.net + as well as in DocBook form in Documentation/DocBook/. If + unsure, say N. if KGDB -- cgit v1.2.2 From 29a6d39bf3a890ad1d29e66baa9f4bc8d9334f3a Mon Sep 17 00:00:00 2001 From: Yi Yang Date: Tue, 12 Aug 2008 15:08:58 -0700 Subject: lib/vsprintf.c: wrong conversion function used Fix wrong conversion function used by strict_strtou* Signed-off-by: Yi Yang Reported-by: Swen Schillig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/vsprintf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 1dc2d1d18fa8..d8d1d1142248 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -220,7 +220,7 @@ int strict_strtou##type(const char *cp, unsigned int base, valtype *res)\ if (len == 0) \ return -EINVAL; \ \ - val = simple_strtoul(cp, &tail, base); \ + val = simple_strtou##type(cp, &tail, base); \ if ((*tail == '\0') || \ ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {\ *res = val; \ -- cgit v1.2.2 From 50ac2d694f2dd1658341cf97bcf2ffb836d772cb Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 12 Aug 2008 15:09:02 -0700 Subject: seq_file: add seq_cpumask(), seq_nodemask() Short enough reads from /proc/irq/*/smp_affinity return -EINVAL for no good reason. This became noticed with NR_CPUS=4096 patches, when length of printed representation of cpumask becase 1152, but cat(1) continued to read with 1024-byte chunks. bitmap_scnprintf() in good faith fills buffer, returns 1023, check returns -EINVAL. Fix it by switching to seq_file, so handler will just fill buffer and doesn't care about offsets, length, filling EOF and all this crap. For that add seq_bitmap(), and wrappers around it -- seq_cpumask() and seq_nodemask(). Signed-off-by: Alexey Dobriyan Reviewed-by: Paul Jackson Cc: Mike Travis Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/bitmap.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'lib') diff --git a/lib/bitmap.c b/lib/bitmap.c index 482df94ea21e..06fb57c86de0 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -315,6 +315,17 @@ int bitmap_scnprintf(char *buf, unsigned int buflen, } EXPORT_SYMBOL(bitmap_scnprintf); +/** + * bitmap_scnprintf_len - return buffer length needed to convert + * bitmap to an ASCII hex string + * @nr_bits: number of bits to be converted + */ +int bitmap_scnprintf_len(unsigned int nr_bits) +{ + unsigned int nr_nibbles = ALIGN(nr_bits, 4) / 4; + return nr_nibbles + ALIGN(nr_nibbles, CHUNKSZ / 4) / (CHUNKSZ / 4) - 1; +} + /** * __bitmap_parse - convert an ASCII hex string into a bitmap. * @buf: pointer to buffer containing string. -- cgit v1.2.2 From 3794f3e812ef707a4f7931742274d1d0ca6597b4 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Tue, 12 Aug 2008 15:09:06 -0700 Subject: docsrc: build Documentation/ sources Currently source files in the Documentation/ sub-dir can easily bit-rot since they are not generally buildable, either because they are hidden in text files or because there are no Makefile rules for them. This needs to be fixed so that the source files remain usable and good examples of code instead of bad examples. Add the ability to build source files that are in the Documentation/ dir. Add to Kconfig as "BUILD_DOCSRC" config symbol. Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the Documentation/ sources. Or enable BUILD_DOCSRC in the *config system. However, this symbol depends on HEADERS_CHECK since the header files need to be installed (for userspace builds). Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32, sparc64, powerpc, sh, m68k, & mips. Signed-off-by: Randy Dunlap Reviewed-by: Sam Ravnborg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index e1d4764435ed..800ac8485544 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -735,6 +735,15 @@ config FIREWIRE_OHCI_REMOTE_DMA If unsure, say N. +menuconfig BUILD_DOCSRC + bool "Build targets in Documentation/ tree" + depends on HEADERS_CHECK + help + This option attempts to build objects from the source files in the + kernel Documentation/ tree. + + Say N if you are unsure. + source "samples/Kconfig" source "lib/Kconfig.kgdb" -- cgit v1.2.2 From ebb1951d3624c2f961abe676645c13e5a1145569 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 15 Aug 2008 19:57:57 -0700 Subject: lmb: Fix reserved region handling in lmb_enforce_memory_limit(). The idea of the implementation of this fix is from Michael Ellerman. This function has two loops, but they each interpret the memory_limit value differently. The first loop interprets it as a "size limit" whereas the second loop interprets it as an "address limit". Before the second loop runs, reset memory_limit to lmb_end_of_DRAM() so that it all works out. Signed-off-by: David S. Miller Acked-by: Michael Ellerman --- lib/lmb.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'lib') diff --git a/lib/lmb.c b/lib/lmb.c index 5d7b9286503e..97e547037084 100644 --- a/lib/lmb.c +++ b/lib/lmb.c @@ -462,6 +462,8 @@ void __init lmb_enforce_memory_limit(u64 memory_limit) if (lmb.memory.region[0].size < lmb.rmo_size) lmb.rmo_size = lmb.memory.region[0].size; + memory_limit = lmb_end_of_DRAM(); + /* And truncate any reserves above the limit also. */ for (i = 0; i < lmb.reserved.cnt; i++) { p = &lmb.reserved.region[i]; -- cgit v1.2.2 From 9e94cd325bb8ed8abe13f29b64fb54c1dec633a8 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sat, 16 Aug 2008 07:53:05 +0200 Subject: Move sysctl check into debugging section and don't make it default y I noticed that sysctl_check.o was the largest object file in a allnoconfig build in kernel/*. 36243 0 0 36243 8d93 kernel/sysctl_check.o This is because it was default y and && EMBEDDED. But I don't really see a need for a non kernel developer to have their sysctls checked all the time. So move the Kconfig into the kernel debugging section and also drop the default y and the EMBEDDED check. Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 800ac8485544..8b5a7d304a5f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -693,6 +693,14 @@ config LATENCYTOP Enable this option if you want to use the LatencyTOP tool to find out which userspace is blocking on what kernel operations. +config SYSCTL_SYSCALL_CHECK + bool "Sysctl checks" + depends on SYSCTL_SYSCALL + ---help--- + sys_sysctl uses binary paths that have been found challenging + to properly maintain and use. This enables checks that help + you to keep things correct. + source kernel/trace/Kconfig config PROVIDE_OHCI1394_DMA_INIT -- cgit v1.2.2