From 05cf96398e1b6502f9e191291b715c7463c9d5dd Mon Sep 17 00:00:00 2001 From: Jianguo Wu Date: Mon, 17 Sep 2012 14:08:56 -0700 Subject: mm/ia64: fix a memory block size bug I found following definition in include/linux/memory.h, in my IA64 platform, SECTION_SIZE_BITS is equal to 32, and MIN_MEMORY_BLOCK_SIZE will be 0. #define MIN_MEMORY_BLOCK_SIZE (1 << SECTION_SIZE_BITS) Because MIN_MEMORY_BLOCK_SIZE is int type and length of 32bits, so MIN_MEMORY_BLOCK_SIZE(1 << 32) will will equal to 0. Actually when SECTION_SIZE_BITS >= 31, MIN_MEMORY_BLOCK_SIZE will be wrong. This will cause wrong system memory infomation in sysfs. I think it should be: #define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) And "echo offline > memory0/state" will cause following call trace: kernel BUG at mm/memory_hotplug.c:885! sh[6455]: bugcheck! 0 [1] Pid: 6455, CPU 0, comm: sh psr : 0000101008526030 ifs : 8000000000000fa4 ip : [] Not tainted (3.6.0-rc1) ip is at offline_pages+0x210/0xee0 Call Trace: show_stack+0x80/0xa0 show_regs+0x640/0x920 die+0x190/0x2c0 die_if_kernel+0x50/0x80 ia64_bad_break+0x3d0/0x6e0 ia64_native_leave_kernel+0x0/0x270 offline_pages+0x210/0xee0 alloc_pages_current+0x180/0x2a0 Signed-off-by: Jianguo Wu Signed-off-by: Jiang Liu Cc: "Luck, Tony" Reviewed-by: Michal Hocko Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memory.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/memory.h b/include/linux/memory.h index 1ac7f6e..ff9a9f8 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -19,7 +19,7 @@ #include #include -#define MIN_MEMORY_BLOCK_SIZE (1 << SECTION_SIZE_BITS) +#define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS) struct memory_block { unsigned long start_section_nr; -- cgit v1.1 From 35c448a8a3471b95ebc0ebcf91eb1183401b4274 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 17 Sep 2012 14:09:11 -0700 Subject: include/net/sock.h: squelch compiler warning in sk_rmem_schedule() This warning: In file included from linux/include/linux/tcp.h:227:0, from linux/include/linux/ipv6.h:221, from linux/include/net/ipv6.h:16, from linux/include/linux/sunrpc/clnt.h:26, from linux/net/sunrpc/stats.c:22: linux/include/net/sock.h: In function `sk_rmem_schedule': linux/nfs-2.6/include/net/sock.h:1339:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] is seen with gcc (GCC) 4.6.3 20120306 (Red Hat 4.6.3-2) using the -Wextra option. Commit c76562b6709f ("netvm: prevent a stream-specific deadlock") accidentally replaced the "size" parameter of sk_rmem_schedule() with an unsigned int. This changes the semantics of the comparison in the return statement. In sk_wmem_schedule we have syntactically the same comparison, but "size" is a signed integer. In addition, __sk_mem_schedule() takes a signed integer for its "size" parameter, so there is an implicit type conversion in sk_rmem_schedule() anyway. Revert the "size" parameter back to a signed integer so that the semantics of the expressions in both sk_[rw]mem_schedule() are exactly the same. Signed-off-by: Chuck Lever Signed-off-by: Mel Gorman Cc: David Miller Cc: Joonsoo Kim Cc: David Rientjes Cc: Pekka Enberg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/net/sock.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index 72132ae..adb7da2 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1332,7 +1332,7 @@ static inline bool sk_wmem_schedule(struct sock *sk, int size) } static inline bool -sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, unsigned int size) +sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) { if (!sk_has_account(sk)) return true; -- cgit v1.1 From 9a858dc7cebce01a7bb616bebb85087fa2b40871 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Mon, 17 Sep 2012 14:09:15 -0700 Subject: compiler.h: add __visible gcc 4.6+ has support for a externally_visible attribute that prevents the optimizer from optimizing unused symbols away. Add a __visible macro to use it with that compiler version or later. This is used (at least) by the "Link Time Optimization" patchset. Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compiler-gcc4.h | 7 +++++++ include/linux/compiler.h | 4 ++++ 2 files changed, 11 insertions(+) (limited to 'include') diff --git a/include/linux/compiler-gcc4.h b/include/linux/compiler-gcc4.h index 2f40791..934bc34 100644 --- a/include/linux/compiler-gcc4.h +++ b/include/linux/compiler-gcc4.h @@ -49,6 +49,13 @@ #endif #endif +#if __GNUC_MINOR__ >= 6 +/* + * Tell the optimizer that something else uses this function or variable. + */ +#define __visible __attribute__((externally_visible)) +#endif + #if __GNUC_MINOR__ > 0 #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) #endif diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 923d093..f430e41 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -278,6 +278,10 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); # define __section(S) __attribute__ ((__section__(#S))) #endif +#ifndef __visible +#define __visible +#endif + /* Are two types/vars the same type (ignoring qualifiers)? */ #ifndef __same_type # define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) -- cgit v1.1