user/sven/linux.git/include/linux/compiler-gcc.h, branch v3.18.104

compiler-gcc: disable -ftracer for __noclone functions

2016-04-20T13:40:50Z

[ Upstream commit 95272c29378ee7dc15f43fa2758cb28a5913a06d ] -ftracer can duplicate asm blocks causing compilation to fail in noclone functions. For example, KVM declares a global variable in an asm like asm("2: ... \n .pushsection data \n .global vmx_return \n vmx_return: .long 2b"); and -ftracer causes a double declaration. Cc: Andrew Morton Cc: Michal Marek Cc: stable@vger.kernel.org Cc: kvm@vger.kernel.org Reported-by: Linda Walsh Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin

compiler-gcc: integrate the various compiler-gcc[345].h files

2016-04-20T13:40:49Z

[ Upstream commit f320793e52aee78f0fbb8bcaf10e6614d2e67bfc ] [ Upstream commit cb984d101b30eb7478d32df56a0023e4603cba7f ] As gcc major version numbers are going to advance rather rapidly in the future, there's no real value in separate files for each compiler version. Deduplicate some of the macros #defined in each file too. Neaten comments using normal kernel commenting style. Signed-off-by: Joe Perches Cc: Andi Kleen Cc: Michal Marek Cc: Segher Boessenkool Cc: Sasha Levin Cc: Anton Blanchard Cc: Alan Modra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

crypto: more robust crypto_memneq

2013-12-05T13:28:41Z

Disabling compiler optimizations can be fragile, since a new optimization could be added to -O0 or -Os that breaks the assumptions the code is making. Instead of disabling compiler optimizations, use a dummy inline assembly (based on RELOC_HIDE) to block the problematic kinds of optimization, while still allowing other optimizations to be applied to the code. The dummy inline assembly is added after every OR, and has the accumulator variable as its input and output. The compiler is forced to assume that the dummy inline assembly could both depend on the accumulator variable and change the accumulator variable, so it is forced to compute the value correctly before the inline assembly, and cannot assume anything about its value after the inline assembly. This change should be enough to make crypto_memneq work correctly (with data-independent timing) even if it is inlined at its call sites. That can be done later in a followup patch. Compile-tested on x86_64. Signed-off-by: Cesar Eduardo Barros Acked-by: Daniel Borkmann Signed-off-by: Herbert Xu

compiler-gcc.h: Add gcc-recommended GCC_VERSION macro

2013-02-22T01:22:15Z

Throughout compiler*.h, many version checks are made. These can be simplified by using the macro that gcc's documentation recommends. However, my primary reason for adding this is that I need bug-check macros that are enabled at certain gcc versions and it's cleaner to use this macro than the tradition method: #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ => 2) If you add patch level, it gets this ugly: #if __GNUC__ > 4 || (__GNUC__ == 4 && (__GNUC_MINOR__ > 2 || \ __GNUC_MINOR__ == 2 __GNUC_PATCHLEVEL__ >= 1)) As opposed to: #if GCC_VERSION >= 40201 While having separate headers for gcc 3 & 4 eliminates some of this verbosity, they can still be cleaned up by this. See also: http://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html Signed-off-by: Daniel Santos Acked-by: Borislav Petkov Acked-by: David Rientjes Cc: Andi Kleen Cc: Joe Perches Cc: Josh Triplett Cc: Paul Gortmaker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ftrace: Make all inline tags also include notrace

2012-06-18T13:47:00Z

Commit 5963e317b1e9d2a ("ftrace/x86: Do not change stacks in DEBUG when calling lockdep") prevented lockdep calls from the int3 breakpoint handler from reseting the stack if a function that was called was in the process of being converted for tracing and had a breakpoint on it. The idea is, before calling the lockdep code, do a load_idt() to the special IDT that kept the breakpoint stack from reseting. This worked well as a quick fix for this kernel release, until a certain config caused a lockup in the function tracer start up tests. Investigating it, I found that the load_idt that was used to prevent the int3 from changing stacks was itself being traced! Even though the config had CONFIG_OPTIMIZE_INLINING disabled, and all 'inline' tags were set to always inline, there were still cases that it did not inline! This was caused by CONFIG_PARAVIRT_GUEST, where it would add a pointer to the native_load_idt() which made that function to be traced. Commit 45959ee7aa645815a ("ftrace: Do not function trace inlined functions") only touched the 'inline' tags when CONFIG_OPMITIZE_INLINING was enabled. PARAVIRT_GUEST shows that this was not enough and we need to also mark always_inline with notrace as well. Reported-by: Fengguang Wu Tested-by: Fengguang Wu Signed-off-by: Steven Rostedt

include/ and checkpatch: prefer scanf to attribute__((format(scanf,...)

2012-03-23T23:58:36Z

It's equivalent to __printf, so prefer __scanf. Signed-off-by: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ftrace: Do not function trace inlined functions

2011-12-21T12:14:34Z

When gcc inlines a function, it does not mark it with the mcount prologue, which in turn means that inlined functions are not traced by the function tracer. But if CONFIG_OPTIMIZE_INLINING is set, then gcc is allowed not to inline a function that is marked inline. Depending on the options and the compiler, a function may or may not be traced by the function tracer, depending on whether gcc decides to inline a function or not. This has caused several problems in the pass becaues gcc is not always consistent with what it decides to inline between different gcc versions. Some places should not be traced (like paravirt native_* functions) and these are mostly marked as inline. When gcc decides not to inline the function, and if that function should not be traced, then the ftrace function tracer will suddenly break when it use to work fine. This becomes even harder to debug when different versions of gcc will not inline that function, making the same kernel and config work for some gcc versions and not work for others. By making all functions marked inline to not be traced will remove the ambiguity that gcc adds when it comes to tracing functions marked inline. All gcc versions will be consistent with what functions are traced and having volatile working code will be removed. Note, only the inline macro when CONFIG_OPTIMIZE_INLINING is set needs to have notrace added, as the attribute __always_inline will force the function to be inlined and then not traced. Signed-off-by: Steven Rostedt

sparse: define __must_be_array() for CHECKER

2011-05-25T15:39:46Z

commit c5e631cf65f ("ARRAY_SIZE: check for type") added __must_be_array(). But sparse can't parse this gcc extention. Now make C=2 makes following sparse errors a lot. kernel/futex.c:2699:25: error: No right hand side of '+'-expression Because __must_be_array() is used for ARRAY_SIZE() macro and it is used very widely. This patch fixes it. Signed-off-by: KOSAKI Motohiro Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

include/linux/compiler-gcc*.h: unify macro definitions

2011-03-23T00:44:10Z

Unify identical gcc3.x and gcc4.x macros. Signed-off-by: Borislav Petkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

include/linux/compiler-gcc.h: use __same_type() in __must_be_array()

2010-08-10T03:45:04Z

We should use the __same_type() helper in __must_be_array(). Signed-off-by: Rusty Russell Reported-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds