aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-x86/system.h
Commit message (Collapse)AuthorAge
* x86: add memory clobber in switch_to()Vegard Nossum2008-10-13
| | | | | | | | | | | Segment registers are reloaded, so we should add a memory clobber. The generated assembly code is identical in my tests, but this doesn't mean it is necessarily true for all configurations/compilers. x86_64 already has the memory clobber. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: consolidate header guardsVegard Nossum2008-07-22
| | | | | | | | | | | | | | | This patch is the result of an automatic script that consolidates the format of all the headers in include/asm-x86/. The format: 1. No leading underscore. Names with leading underscores are reserved. 2. Pathname components are separated by two underscores. So we can distinguish between mm_types.h and mm/types.h. 3. Everything except letters and numbers are turned into single underscores. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
* x86: fix savesegment() bug causing crashes on 64-bitIngo Molnar2008-07-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | i spent a fair amount of time chasing a 64-bit bootup crash that manifested itself as bootup segfaults: S10network[1825]: segfault at 7f3e2b5d16b8 ip 00000031108748c9 sp 00007fffb9c14c70 error 4 in libc-2.7.so[3110800000+14d000] eventually causing init to die and panic the system: Kernel panic - not syncing: Attempted to kill init! Pid: 1, comm: init Not tainted 2.6.26-rc9-tip #13878 after a maratonic bisection session, the bad commit turned out to be: | b7675791859075418199c7af86a116ea34eaf5bd is first bad commit | commit b7675791859075418199c7af86a116ea34eaf5bd | Author: Jeremy Fitzhardinge <jeremy@goop.org> | Date: Wed Jun 25 00:19:00 2008 -0400 | | x86: remove open-coded save/load segment operations | | This removes a pile of buggy open-coded implementations of savesegment | and loadsegment. after some more bisection of this patch itself, it turns out that what makes the difference are the savesegment() changes to __switch_to(). Taking a look at this portion of arch/x86/kernel/process_64.o revealed this crutial difference: | good: 99c: 8c e0 mov %fs,%eax | 99e: 89 45 cc mov %eax,-0x34(%rbp) | | bad: 99c: 8c 65 cc mov %fs,-0x34(%rbp) which is due to: | unsigned fsindex; | - asm volatile("movl %%fs,%0" : "=r" (fsindex)); | + savesegment(fs, fsindex); savesegment() is implemented as: #define savesegment(seg, value) \ asm("mov %%" #seg ",%0":"=rm" (value) : : "memory") note the "m" modifier - it allows GCC to generate the segment move into a memory operand as well. But regarding segment operands there's a subtle detail in the x86 instruction set: the above 16-bit moves are zero-extend, but only if it goes to a register. If it goes to a memory operand, -0x34(%rbp) in the above case, there's no zero-extend to 32-bit and the instruction will only save 16 bits instead of the intended 32-bit. The other 16 bits is random data - which can cause problems when that value is used later on. The solution is to only allow segment operands to go to registers. This fix allows my test-system to boot up without crashing. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86/paravirt, 64-bit: make load_gs_index() a paravirt operationJeremy Fitzhardinge2008-07-08
| | | | | | | | | | Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: add memory clobber to save/loadsegmentJeremy Fitzhardinge2008-07-08
| | | | | | | | | | | | | Add "memory" clobbers to savesegment and loadsegment, since they can affect memory accesses and we never want the compiler to reorder them with respect to memory references. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: xen-devel <xen-devel@lists.xensource.com> Cc: Stephen Tweedie <sct@redhat.com> Cc: Eduardo Habkost <ehabkost@redhat.com> Cc: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'x86/mpparse' into x86/develIngo Molnar2008-07-08
|\ | | | | | | | | | | | | | | | | | | | | Conflicts: arch/x86/Kconfig arch/x86/kernel/io_apic_32.c arch/x86/kernel/setup_64.c arch/x86/mm/init_32.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * x86: move es7000_plat out of mpparse.cAlexey Starikovskiy2008-05-25
| | | | | | | | | | Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | x86: use symbolic constant in stts()Jeremy Fitzhardinge2008-05-27
|/ | | | | Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* include/asm-x86/system.h: checkpatch cleanups - formatting onlyJoe Perches2008-04-17
| | | | | Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: fix switch_to() clobbersIngo Molnar2008-04-17
| | | | | | | | | | | | | | | | | | | Liu Pingfan noticed that switch_to() clobbers more registers than its asm constraints specify. We get away with this due to luck mostly - schedule() by its nature only has 'local' state which gets reloaded automatically. Fix it nevertheless, we could hit this anytime. it turns out that with the extra constraints gcc manages to make schedule() even more compact: text data bss dec hex filename 28626 684 2640 31950 7cce sched.o.before 28613 684 2640 31937 7cc1 sched.o.after Reported-by: Liu Pingfan <kernelfans@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: clean up switch_to()Ingo Molnar2008-04-17
| | | | | | | | | | | | | | | | | | | | | | Make the code more readable and more hackable: - use symbolic asm parameters - use readable indentation - add comments that explains the details No code changed: kernel/sched.o: text data bss dec hex filename 28626 684 2640 31950 7cce sched.o.before 28626 684 2640 31950 7cce sched.o.after md5: 2823d406c18b781975cdb2e7cfea0059 sched.o.before.asm 2823d406c18b781975cdb2e7cfea0059 sched.o.after.asm Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: wmb() confusion in system.hPavel Machek2008-04-17
| | | | | | | | | | | Comment says wmb is a nop, but it is implemented as lock addl below... Should it be compiled to nop if we know we are running on "good" Intel cpu? At least remove confusing comment for now. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: remove final FASTCALL() usesHarvey Harrison2008-02-04
| | | | | | | | A few snuck back in to x86. Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: reintroduce volatile keyword in prototype to clflush()H. Peter Anvin2008-02-04
| | | | | | | | | | | | | | | | | | | | The volatile keyword was removed from the clflush() prototype in commit e34907ae180f4fe6c28bb4516c679c2f81b0c9ed; the comment there states: x86: remove volatile keyword from clflush. the p parameter is an explicit memory reference, and is enough to prevent gcc to being nasty here. The volatile seems completely not needed. This reflects incorrect understanding of the function of the volatile keyword there. The purpose of the volatile keyword is informing gcc that it is safe to pass a volatile pointer to this function. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: use _ASM_EXTABLE macro in include/asm-x86/system.hH. Peter Anvin2008-02-04
| | | | | | | | | Use the _ASM_EXTABLE macro from <asm/asm.h>, instead of open-coding __ex_table entires in include/asm-x86/system.h. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: provide read and write cr8 paravirt hooksGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | | | Since the cr8 manipulation functions ended up staying in the tree, they can't be defined just when PARAVIRT is off: In this patch, those functions are defined for the PARAVIRT case too. [ mingo@elte.hu: fixes ] Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: introduce rdtsc_barrier()Andi Kleen2008-01-30
| | | | | | | | | | | | | | | | rdtsc_barrier() is a new barrier primitive that stops RDTSC speculation to avoid races with timer interrupts on other CPUs. It expands either to LFENCE (for Intel CPUs) or MFENCE (for AMD CPUs) which stops RDTSC on all currently known microarchitectures that implement SSE. On CPUs without SSE there is generally no RDTSC speculation. [ mingo@elte.hu: renamed it to rdtsc_barrier() and made it x86-only ] Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: also define AT_VECTOR_SIZE_ARCHJan Beulich2008-01-30
| | | | | | | | | | | The patch introducing this left out x86-64, despite it also having extra entries. [ mingo@elte.hu: re-merged this to after the unification patches. ] Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: unify system.hGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | | | | | This patch finishes the unification of system.h file. i386 needs a constant to be defined, and it is defined inside an ifdef. Other than that, pretty much nothing but includes are left in the arch specific headers, and they are deleted. [ mingo@elte.hu: 64-bit needs the cr8 access inlines. ] Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: move switch_to macro to system.hGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | | This patch moves the switch_to() macro to system.h As those macros are fundamentally different between i386 and x86_64, they are enclosed around an ifdef. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: unify smp parts of system.hGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | | | | The memory barrier parts of system.h are not very different between i386 and x86_64, the main difference being the availability of instructions, which we handle with the use of ifdefs. They are consolidated in system.h file, and then removed from the arch-specific headers. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: unify paravirt parts of system.hGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | | | | | This patch moves the i386 control registers manipulation functions, wbinvd, and clts functions to system.h. They are essentially the same as in x86_64. With this, system.h paravirt comes for free in x86_64. [ mingo@elte.hu: reintroduced the cr8 bits - needed for resume images ] Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: unify load_segment macroGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | This patch unifies the load_segment() macro, making them equal in both x86_64 and i386 architectures. The common version goes to system.h, and the old are deleted. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: put together equal pieces of system.hGlauber de Oliveira Costa2008-01-30
| | | | | | | | | | This patch puts together pieces of system_{32,64}.h that looks like the same. It's the first step towards integration of this file. Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* i386/x86_64: move headers to include/asm-x86Thomas Gleixner2007-10-11
Move the headers to include/asm-x86 and fixup the header install make rules Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-26 23:12:15 -0500