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2013-09-28lockdep, x86/alternatives: Drop ancient lockdep fixup messageBorislav Petkov1-11/+0
It messes up the output of the nodes/cores bootup table and it is obsolete anyway, see 17abecfe651c x86: fix up alternatives with lockdep enabled Signed-off-by: Borislav Petkov <bp@suse.de> Cc: huawei.libin@huawei.com Cc: wangyijing@huawei.com Cc: fenghua.yu@intel.com Cc: guohanjun@huawei.com Cc: paul.gortmaker@windriver.com Link: http://lkml.kernel.org/r/20130927143442.GE4422@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-23kprobes/x86: Call out into INT3 handler directly instead of using notifierJiri Kosina1-23/+8
In fd4363fff3d96 ("x86: Introduce int3 (breakpoint)-based instruction patching"), the mechanism that was introduced for notifying alternatives code from int3 exception handler that and exception occured was die_notifier. This is however problematic, as early code might be using jump labels even before the notifier registration has been performed, which will then lead to an oops due to unhandled exception. One of such occurences has been encountered by Fengguang: int3: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.11.0-rc1-01429-g04bf576 #8 task: ffff88000da1b040 ti: ffff88000da1c000 task.ti: ffff88000da1c000 RIP: 0010:[<ffffffff811098cc>] [<ffffffff811098cc>] ttwu_do_wakeup+0x28/0x225 RSP: 0000:ffff88000dd03f10 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff88000dd12940 RCX: ffffffff81769c40 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88000dd03f28 R08: ffffffff8176a8c0 R09: 0000000000000002 R10: ffffffff810ff484 R11: ffff88000dd129e8 R12: ffff88000dbc90c0 R13: ffff88000dbc90c0 R14: ffff88000da1dfd8 R15: ffff88000da1dfd8 FS: 0000000000000000(0000) GS:ffff88000dd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000000ffffffff CR3: 0000000001c88000 CR4: 00000000000006e0 Stack: ffff88000dd12940 ffff88000dbc90c0 ffff88000da1dfd8 ffff88000dd03f48 ffffffff81109e2b ffff88000dd12940 0000000000000000 ffff88000dd03f68 ffffffff81109e9e 0000000000000000 0000000000012940 ffff88000dd03f98 Call Trace: <IRQ> [<ffffffff81109e2b>] ttwu_do_activate.constprop.56+0x6d/0x79 [<ffffffff81109e9e>] sched_ttwu_pending+0x67/0x84 [<ffffffff8110c845>] scheduler_ipi+0x15a/0x2b0 [<ffffffff8104dfb4>] smp_reschedule_interrupt+0x38/0x41 [<ffffffff8173bf5d>] reschedule_interrupt+0x6d/0x80 <EOI> [<ffffffff810ff484>] ? __atomic_notifier_call_chain+0x5/0xc1 [<ffffffff8105cc30>] ? native_safe_halt+0xd/0x16 [<ffffffff81015f10>] default_idle+0x147/0x282 [<ffffffff81017026>] arch_cpu_idle+0x3d/0x5d [<ffffffff81127d6a>] cpu_idle_loop+0x46d/0x5db [<ffffffff81127f5c>] cpu_startup_entry+0x84/0x84 [<ffffffff8104f4f8>] start_secondary+0x3c8/0x3d5 [...] Fix this by directly calling poke_int3_handler() from the int3 exception handler (analogically to what ftrace has been doing already), instead of relying on notifier, registration of which might not have yet been finalized by the time of the first trap. Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1307231007490.14024@pobox.suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-19kprobes/x86: Remove unused text_poke_smp() and text_poke_smp_batch() functionsMasami Hiramatsu1-96/+2
Since introducing the text_poke_bp() for all text_poke_smp*() callers, text_poke_smp*() are now unused. This patch basically reverts: 3d55cc8a058e ("x86: Add text_poke_smp for SMP cross modifying code") 7deb18dcf047 ("x86: Introduce text_poke_smp_batch() for batch-code modifying") and related commits. This patch also fixes a Kconfig dependency issue on STOP_MACHINE in the case of CONFIG_SMP && !CONFIG_MODULE_UNLOAD. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Jiri Kosina <jkosina@suse.cz> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jason Baron <jbaron@akamai.com> Cc: yrl.pp-manager.tt@hitachi.com Cc: Borislav Petkov <bpetkov@suse.de> Link: http://lkml.kernel.org/r/20130718114753.26675.18714.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-16x86: Introduce int3 (breakpoint)-based instruction patchingJiri Kosina1-0/+106
Introduce a method for run-time instruction patching on a live SMP kernel based on int3 breakpoint, completely avoiding the need for stop_machine(). The way this is achieved: - add a int3 trap to the address that will be patched - sync cores - update all but the first byte of the patched range - sync cores - replace the first byte (int3) by the first byte of replacing opcode - sync cores According to http://lkml.indiana.edu/hypermail/linux/kernel/1001.1/01530.html synchronization after replacing "all but first" instructions should not be necessary (on Intel hardware), as the syncing after the subsequent patching of the first byte provides enough safety. But there's not only Intel HW out there, and we'd rather be on a safe side. If any CPU instruction execution would collide with the patching, it'd be trapped by the int3 breakpoint and redirected to the provided "handler" (which would typically mean just skipping over the patched region, acting as "nop" has been there, in case we are doing nop -> jump and jump -> nop transitions). Ftrace has been using this very technique since 08d636b ("ftrace/x86: Have arch x86_64 use breakpoints instead of stop machine") for ages already, and jump labels are another obvious potential user of this. Based on activities of Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> a few years ago. Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1307121102440.29788@pobox.suse.cz Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-02x86, cpu: Expand cpufeature facility to include cpu bugsBorislav Petkov1-1/+1
We add another 32-bit vector at the end of the ->x86_capability bitvector which collects bugs present in CPUs. After all, a CPU bug is a kind of a capability, albeit a strange one. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1363788448-31325-2-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-10-01Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-2/+2
Pull x86/cleanups from Ingo Molnar: "Smaller cleanups" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arch/x86: Remove unecessary semicolons x86, boot: Remove obsolete and unused constant RAMDISK
2012-10-01Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-81/+26
Pull x86/asm changes from Ingo Molnar: "The one change that stands out is the alternatives patching change that prevents us from ever patching back instructions from SMP to UP: this simplifies things and speeds up CPU hotplug. Other than that it's smaller fixes, cleanups and improvements." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Unspaghettize do_trap() x86_64: Work around old GAS bug x86: Use REP BSF unconditionally x86: Prefer TZCNT over BFS x86/64: Adjust types of temporaries used by ffs()/fls()/fls64() x86: Drop unnecessary kernel_eflags variable on 64-bit x86/smp: Don't ever patch back to UP if we unplug cpus
2012-09-19arch/x86: Remove unecessary semicolonsPeter Senna Tschudin1-2/+2
Found by http://coccinelle.lip6.fr/ Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com> Cc: avi@redhat.com Cc: mtosatti@redhat.com Cc: a.p.zijlstra@chello.nl Cc: rusty@rustcorp.com.au Cc: masami.hiramatsu.pt@hitachi.com Cc: suresh.b.siddha@intel.com Cc: joerg.roedel@amd.com Cc: agordeev@redhat.com Cc: yinghai@kernel.org Cc: bhelgaas@google.com Cc: liuj97@gmail.com Link: http://lkml.kernel.org/r/1347986174-30287-7-git-send-email-peter.senna@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-23x86/smp: Don't ever patch back to UP if we unplug cpusRusty Russell1-81/+26
We still patch SMP instructions to UP variants if we boot with a single CPU, but not at any other time. In particular, not if we unplug CPUs to return to a single cpu. Paul McKenney points out: mean offline overhead is 6251/48=130.2 milliseconds. If I remove the alternatives_smp_switch() from the offline path [...] the mean offline overhead is 550/42=13.1 milliseconds Basically, we're never going to get those 120ms back, and the code is pretty messy. We get rid of: 1) The "smp-alt-once" boot option. It's actually "smp-alt-boot", the documentation is wrong. It's now the default. 2) The skip_smp_alternatives flag used by suspend. 3) arch_disable_nonboot_cpus_begin() and arch_disable_nonboot_cpus_end() which were only used to set this one flag. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul McKenney <paul.mckenney@us.ibm.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/87vcgwwive.fsf@rustcorp.com.au Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-22x86/alternatives: Fix p6 nops on non-modular kernelsAvi Kivity1-1/+1
Probably a leftover from the early days of self-patching, p6nops are marked __initconst_or_module, which causes them to be discarded in a non-modular kernel. If something later triggers patching, it will overwrite kernel code with garbage. Reported-by: Tomas Racek <tracek@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Cc: Michael Tokarev <mjt@tls.msk.ru> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: qemu-devel@nongnu.org Cc: Anthony Liguori <anthony@codemonkey.ws> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/r/5034AE84.90708@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-25Merge branch 'linus' into x86/urgentIngo Molnar1-7/+12
Merge in Linus's tree to avoid a conflict. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-07-25x86, nops: Missing break resulting in incorrect selection on IntelAlan Cox1-1/+1
The Intel case falls through into the generic case which then changes the values. For cases like the P6 it doesn't do the right thing so this seems to be a screwup. Signed-off-by: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/n/tip-lww2uirad4skzjlmrm0vru8o@git.kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@vger.kernel.org>
2012-07-22Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-6/+11
Pull debug-for-linus git tree from Ingo Molnar. Fix up trivial conflict in arch/x86/kernel/cpu/perf_event_intel.c due to a printk() having changed to a pr_info() differently in the two branches. * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move call to print_modules() out of show_regs() x86/mm: Mark free_initrd_mem() as __init x86/microcode: Mark microcode_id[] as __initconst x86/nmi: Clean up register_nmi_handler() usage x86: Save cr2 in NMI in case NMIs take a page fault (for i386) x86: Remove cmpxchg from i386 NMI nesting code x86: Save cr2 in NMI in case NMIs take a page fault x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>
2012-06-13x86/alternatives: Use atomic_xchg() instead atomic_dec_and_test() for stop_machine_text_poke()OGAWA Hirofumi1-1/+1
stop_machine_text_poke() uses atomic_dec_and_test() to select one of the CPUs executing that function to actually modify the code. Since the variable is initialized to 1, subsequent CPUs will make the variable go negative. Since going negative is uncommon/unexpected in typical dec_and_test usage change this user to atomic_xchg(). This was found using a patch that warns on dec_and_test going negative. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Acked-by: Steven Rostedt <rostedt@goodmis.org> [ Rewrote changelog ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/87zk8fgsx9.fsf@devron.myhome.or.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-06x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>Joe Perches1-6/+11
Use a more current logging style: - Bare printks should have a KERN_<LEVEL> for consistency's sake - Add pr_fmt where appropriate - Neaten some macro definitions - Convert some Ok output to OK - Use "%s: ", __func__ in pr_fmt for summit - Convert some printks to pr_<level> Message output is not identical in all cases. Signed-off-by: Joe Perches <joe@perches.com> Cc: levinsasha928@gmail.com Link: http://lkml.kernel.org/r/1337655007.24226.10.camel@joe2Laptop [ merged two similar patches, tidied up the changelog ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2011-11-14x86: Call stop_machine_text_poke() on all CPUsRabin Vincent1-1/+1
It appears that stop_machine_text_poke() wants to be called on all CPUs, like it's done from text_poke_smp(). Fix text_poke_smp_batch() to do this. Signed-off-by: Rabin Vincent <rabin@rab.in> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1319702072-32676-1-git-send-email-rabin@rab.in Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-14x86-64: Move vread_tsc and vread_hpet into the vDSOAndy Lutomirski1-8/+0
The vsyscall page now consists entirely of trap instructions. Cc: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/637648f303f2ef93af93bae25186e9a1bea093f5.1310639973.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-07-13x86: Make alternative instruction pointers relativeAndy Lutomirski1-8/+13
This save a few bytes on x86-64 and means that future patches can apply alternatives to unrelocated code. Signed-off-by: Andy Lutomirski <luto@mit.edu> Link: http://lkml.kernel.org/r/ff64a6b9a1a3860ca4a7b8b6dc7b4754f9491cd7.1310563276.git.luto@mit.edu Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-05-19Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-82/+112
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, cpu: Fix detection of Celeron Covington stepping A1 and B0 Documentation, ABI: Update L3 cache index disable text x86, AMD, cacheinfo: Fix L3 cache index disable checks x86, AMD, cacheinfo: Fix fallout caused by max3 conversion x86, cpu: Change NOP selection for certain Intel CPUs x86, cpu: Clean up and unify the NOP selection infrastructure x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4 x86, cpu: Move AMD Elan Kconfig under "Processor family" Fix up trivial conflicts in alternative handling (commit dc326fca2b64 "x86, cpu: Clean up and unify the NOP selection infrastructure" removed some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to CONFIG_JUMP_LABEL in the code that went away)
2011-05-18Merge branch 'x86/mem' into perf/coreIngo Molnar1-0/+9
Merge reason: memcpy_64.S changes an assumption perf bench has, so merge this here so we can fix it. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-17x86, alternative, doc: Add comment for applying alternatives orderFenghua Yu1-0/+9
Some string operation functions may be patched twice, e.g. on enhanced REP MOVSB /STOSB processors, memcpy is patched first by fast string alternative function, then it is patched by enhanced REP MOVSB/STOSB alternative function. Add comment for applying alternatives order to warn people who may change the applying alternatives order for any reason. [ Documentation-only patch ] Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-4-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-04-18x86, cpu: Change NOP selection for certain Intel CPUsH. Peter Anvin1-1/+13
Due to a decoder implementation quirk, some specific Intel CPUs actually perform better with the "k8_nops" than with the SDM-recommended NOPs. For runtime-selected NOPs, if we detect those specific CPUs then use the k8_nops instead of the ones we would normally use. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1303166160-10315-4-git-send-email-hpa@linux.intel.com
2011-04-18x86, cpu: Clean up and unify the NOP selection infrastructureH. Peter Anvin1-82/+100
Clean up and unify the NOP selection infrastructure: - Make the atomic 5-byte NOP a part of the selection system. - Pick NOPs once during early boot and then be done with it. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jason Baron <jbaron@redhat.com> Link: http://lkml.kernel.org/r/1303166160-10315-3-git-send-email-hpa@linux.intel.com
2011-04-04jump label: Introduce static_branch() interfaceJason Baron1-1/+1
Introduce: static __always_inline bool static_branch(struct jump_label_key *key); instead of the old JUMP_LABEL(key, label) macro. In this way, jump labels become really easy to use: Define: struct jump_label_key jump_key; Can be used as: if (static_branch(&jump_key)) do unlikely code enable/disale via: jump_label_inc(&jump_key); jump_label_dec(&jump_key); that's it! For the jump labels disabled case, the static_branch() becomes an atomic_read(), and jump_label_inc()/dec() are simply atomic_inc(), atomic_dec() operations. We show testing results for this change below. Thanks to H. Peter Anvin for suggesting the 'static_branch()' construct. Since we now require a 'struct jump_label_key *key', we can store a pointer into the jump table addresses. In this way, we can enable/disable jump labels, in basically constant time. This change allows us to completely remove the previous hashtable scheme. Thanks to Peter Zijlstra for this re-write. Testing: I ran a series of 'tbench 20' runs 5 times (with reboots) for 3 configurations, where tracepoints were disabled. jump label configured in avg: 815.6 jump label *not* configured in (using atomic reads) avg: 800.1 jump label *not* configured in (regular reads) avg: 803.4 Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20110316212947.GA8792@redhat.com> Signed-off-by: Jason Baron <jbaron@redhat.com> Suggested-by: H. Peter Anvin <hpa@linux.intel.com> Tested-by: David Daney <ddaney@caviumnetworks.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-18x86: Fix common misspellingsLucas De Marchi1-1/+1
They were generated by 'codespell' and then manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: trivial@kernel.org LKML-Reference: <1300389856-1099-3-git-send-email-lucas.demarchi@profusion.mobi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-15x86: stop_machine_text_poke() should issue sync_core()Mathieu Desnoyers1-1/+6
Intel Archiecture Software Developer's Manual section 7.1.3 specifies that a core serializing instruction such as "cpuid" should be executed on _each_ core before the new instruction is made visible. Failure to do so can lead to unspecified behavior (Intel XMC erratas include General Protection Fault in the list), so we should avoid this at all cost. This problem can affect modified code executed by interrupt handlers after interrupt are re-enabled at the end of stop_machine, because no core serializing instruction is executed between the code modification and the moment interrupts are reenabled. Because stop_machine_text_poke performs the text modification from the first CPU decrementing stop_machine_first, modified code executed in thread context is also affected by this problem. To explain why, we have to split the CPUs in two categories: the CPU that initiates the text modification (calls text_poke_smp) and all the others. The scheduler, executed on all other CPUs after stop_machine, issues an "iret" core serializing instruction, and therefore handles core serialization for all these CPUs. However, the text modification initiator can continue its execution on the same thread and access the modified text without any scheduler call. Given that the CPU that initiates the code modification is not guaranteed to be the one actually performing the code modification, it falls into the XMC errata. Q: Isn't this executed from an IPI handler, which will return with IRET (a serializing instruction) anyway? A: No, now stop_machine uses per-cpu workqueue, so that handler will be executed from worker threads. There is no iret anymore. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> LKML-Reference: <20110303160137.GB1590@Krystal> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: <stable@kernel.org> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-02-12x86: Fix text_poke_smp_batch() deadlockPeter Zijlstra1-1/+1
Fix this deadlock - we are already holding the mutex: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.38-rc4-test+ #1 ------------------------------------------------------- bash/1850 is trying to acquire lock: (text_mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f but task is already holding lock: (smp_alt){+.+...}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (smp_alt){+.+...}: [<ffffffff81082d02>] lock_acquire+0xcd/0xf8 [<ffffffff8192e119>] __mutex_lock_common+0x4c/0x339 [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43 [<ffffffff8101050f>] alternatives_smp_switch+0x77/0x1d8 [<ffffffff81926a6f>] do_boot_cpu+0xd7/0x762 [<ffffffff819277dd>] native_cpu_up+0xe6/0x16a [<ffffffff81928e28>] _cpu_up+0x9d/0xee [<ffffffff81928f4c>] cpu_up+0xd3/0xe7 [<ffffffff82268d4b>] kernel_init+0xe8/0x20a [<ffffffff8100ba24>] kernel_thread_helper+0x4/0x10 -> #1 (cpu_hotplug.lock){+.+.+.}: [<ffffffff81082d02>] lock_acquire+0xcd/0xf8 [<ffffffff8192e119>] __mutex_lock_common+0x4c/0x339 [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43 [<ffffffff810568cc>] get_online_cpus+0x41/0x55 [<ffffffff810a1348>] stop_machine+0x1e/0x3e [<ffffffff819314c1>] text_poke_smp_batch+0x3a/0x3c [<ffffffff81932b6c>] arch_optimize_kprobes+0x10d/0x11c [<ffffffff81933a51>] kprobe_optimizer+0x152/0x222 [<ffffffff8106bb71>] process_one_work+0x1d3/0x335 [<ffffffff8106cfae>] worker_thread+0x104/0x1a4 [<ffffffff810707c4>] kthread+0x9d/0xa5 [<ffffffff8100ba24>] kernel_thread_helper+0x4/0x10 -> #0 (text_mutex){+.+.+.}: other info that might help us debug this: 6 locks held by bash/1850: #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f #1: (s_active#75){.+.+.+}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f #2: (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f #3: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f #4: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f #5: (smp_alt){+.+...}, at: [<ffffffff8100a9c1>] return_to_handler+0x0/0x2f stack backtrace: Pid: 1850, comm: bash Not tainted 2.6.38-rc4-test+ #1 Call Trace: [<ffffffff81080eb2>] print_circular_bug+0xa8/0xb7 [<ffffffff8192e4ca>] mutex_lock_nested+0x3e/0x43 [<ffffffff81010302>] alternatives_smp_unlock+0x3d/0x93 [<ffffffff81010630>] alternatives_smp_switch+0x198/0x1d8 [<ffffffff8102568a>] native_cpu_die+0x65/0x95 [<ffffffff818cc4ec>] _cpu_down+0x13e/0x202 [<ffffffff8117a619>] sysfs_write_file+0x108/0x144 [<ffffffff8111f5a2>] vfs_write+0xac/0xff [<ffffffff8111f7a9>] sys_write+0x4a/0x6e Reported-by: Steven Rostedt <rostedt@goodmis.org> Tested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: mathieu.desnoyers@efficios.com Cc: rusty@rustcorp.com.au Cc: ananth@in.ibm.com Cc: masami.hiramatsu.pt@hitachi.com Cc: fweisbec@gmail.com Cc: jbeulich@novell.com Cc: jbaron@redhat.com Cc: mhiramat@redhat.com LKML-Reference: <1297458466.5226.93.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-06Merge branches 'x86-alternatives-for-linus', 'x86-fpu-for-linus', 'x86-hwmon-for-linus', 'x86-paravirt-for-linus', 'core-locking-for-linus' and 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-1/+2
* 'x86-alternatives-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, suspend: Avoid unnecessary smp alternatives switch during suspend/resume * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64, asm: Use fxsaveq/fxrestorq in more places * 'x86-hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, hwmon: Add core threshold notification to therm_throt.c * 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, paravirt: Use native_halt on a halt, not native_safe_halt * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: locking, lockdep: Convert sprintf_symbol to %pS * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: irq: Better struct irqaction layout
2010-12-13x86, suspend: Avoid unnecessary smp alternatives switch during suspend/resumeSuresh Siddha1-1/+2
During suspend, we disable all the non boot cpus. And during resume we bring them all back again. So no need to do alternatives_smp_switch() in between. On my core 2 based laptop, this speeds up the suspend path by 15msec and the resume path by 5 msec (suspend/resume speed up differences can be attributed to the different P-states that the cpu is in during suspend/resume). Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <1290557500.4946.8.camel@sbsiddha-MOBL3.sc.intel.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-12-06x86: Introduce text_poke_smp_batch() for batch-code modifyingMasami Hiramatsu1-9/+40
Introduce text_poke_smp_batch(). This function modifies several text areas with one stop_machine() on SMP. Because calling stop_machine() is heavy task, it is better to aggregate text_poke requests. ( Note: I've talked with Rusty about this interface, and he would not like to expand stop_machine() interface, since it is not for generic use. ) Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Jan Beulich <jbeulich@novell.com> Cc: 2nddept-manager@sdl.hitachi.co.jp LKML-Reference: <20101203095422.2961.51217.stgit@ltc236.sdl.hitachi.co.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-30Merge branches 'perf-fixes-for-linus' and 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-54/+15
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: jump label: Add work around to i386 gcc asm goto bug x86, ftrace: Use safe noops, drop trap test jump_label: Fix unaligned traps on sparc. jump label: Make arch_jump_label_text_poke_early() optional jump label: Fix error with preempt disable holding mutex oprofile: Remove deprecated use of flush_scheduled_work() oprofile: Fix the hang while taking the cpu offline jump label: Fix deadlock b/w jump_label_mutex vs. text_mutex jump label: Fix module __init section race * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Check irq_remapped instead of remapping_enabled in destroy_irq()
2010-10-29x86, alternative: Call stop_machine_text_poke() on all cpusJason Baron1-1/+1
Currently, text_poke_smp() passes a NULL as the third argument to __stop_machine(), which will only run stop_machine_text_poke() on 1 cpu. Change NULL -> cpu_online_mask, as stop_machine_text_poke() is intended to be run on all cpus. I actually didn't notice any problems with stop_machine_text_poke() only being called on 1 cpu, but found this via code inspection. Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <20101028152026.GB2875@redhat.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-10-29x86, ftrace: Use safe noops, drop trap testH. Peter Anvin1-54/+15
Always use a safe 5-byte noop sequence. Drop the trap test, since it is known to return false negatives on some virtualization platforms on 32 bits. The resulting code is both simpler and safer. Cc: Daniel Drake <dsd@laptop.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-14x86: Use __stop_machine() in text_poke_smp()Masami Hiramatsu1-1/+2
Use __stop_machine() in text_poke_smp() because the caller must get online_cpus before calling text_poke_smp(), but stop_machine() do it again. We don't need it. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: 2nddept-manager@sdl.hitachi.co.jp Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> LKML-Reference: <20101014031036.4100.83989.stgit@ltc236.sdl.hitachi.co.jp> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-22jump label: Base patch for jump labelJason Baron1-1/+1
base patch to implement 'jump labeling'. Based on a new 'asm goto' inline assembly gcc mechanism, we can now branch to labels from an 'asm goto' statment. This allows us to create a 'no-op' fastpath, which can subsequently be patched with a jump to the slowpath code. This is useful for code which might be rarely used, but which we'd like to be able to call, if needed. Tracepoints are the current usecase that these are being implemented for. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <ee8b3595967989fdaf84e698dc7447d315ce972a.1284733808.git.jbaron@redhat.com> [ cleaned up some formating ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-20jump label: Make text_poke_early() globally visibleJason Baron1-2/+2
Make text_poke_early available outside of alternative.c. The jump label patchset wants to make use of it in order to set up the optimal no-op sequences at run-time. Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <04cfddf2ba77bcabfc3e524f1849d871d6a1cf9d.1284733808.git.jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-20jump label: Make dynamic no-op selection available outside of ftraceJason Baron1-0/+64
Move Steve's code for finding the best 5-byte no-op from ftrace.c to alternative.c. The idea is that other consumers (in this case jump label) want to make use of that code. Signed-off-by: Jason Baron <jbaron@redhat.com> LKML-Reference: <96259ae74172dcac99c0020c249743c523a92e18.1284733808.git.jbaron@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-07-13x86, alternatives: BUG on encountering an invalid CPU feature numberH. Peter Anvin1-0/+1
Make the alternatives-patching code BUG on encountering an invalid CPU feature number. Should have done this a long time ago. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Yinghai Lu <yinhai@kernel.org> Cc: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <tip-df378ccfc4dd04e263426ad805516915874774aa@git.kernel.org>
2010-04-29Merge branch 'x86/asm' into x86/atomicH. Peter Anvin1-19/+103
Merge reason: Conflict between LOCK_PREFIX_HERE and relative alternatives pointers Resolved Conflicts: arch/x86/include/asm/alternative.h arch/x86/kernel/alternative.c Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-04-28x86-64: Reduce SMP locks table sizeJan Beulich1-20/+25
Reduce the SMP locks table size by using relative pointers instead of absolute ones, thus cutting the table size by half. Signed-off-by: Jan Beulich <jbeulich@novell.com> LKML-Reference: <4BCF30FE020000780003B3B6@vpn.id2.novell.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.hTejun Heo1-0/+1
percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-05Merge branch 'perf-probes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-0/+60
* 'perf-probes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Issue at least one memory barrier in stop_machine_text_poke() perf probe: Correct probe syntax on command line help perf probe: Add lazy line matching support perf probe: Show more lines after last line perf probe: Check function address range strictly in line finder perf probe: Use libdw callback routines perf probe: Use elfutils-libdw for analyzing debuginfo perf probe: Rename probe finder functions perf probe: Fix bugs in line range finder perf probe: Update perf probe document perf probe: Do not show --line option without dwarf support kprobes: Add documents of jump optimization kprobes/x86: Support kprobes jump optimization on x86 x86: Add text_poke_smp for SMP cross modifying code kprobes/x86: Cleanup save/restore registers kprobes/x86: Boost probes when reentering kprobes: Jump optimization sysctl interface kprobes: Introduce kprobes jump optimization kprobes: Introduce generic insn_slot framework kprobes/x86: Cleanup RELATIVEJUMP_INSTRUCTION to RELATIVEJUMP_OPCODE
2010-03-04x86: Issue at least one memory barrier in stop_machine_text_poke()Masami Hiramatsu1-2/+2
Fix stop_machine_text_poke() to issue smp_mb() before exiting waiting loop, and use cpu_relax() for waiting. Changes in v2: - Don't use ACCESS_ONCE(). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <20100304033850.3819.74590.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-28Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-1/+3
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Mark atomic irq ops raw for 32bit legacy x86: Merge show_regs() x86: Macroise x86 cache descriptors x86-32: clean up rwsem inline asm statements x86: Merge asm/atomic_{32,64}.h x86: Sync asm/atomic_32.h and asm/atomic_64.h x86: Split atomic64_t functions into seperate headers x86-64: Modify memcpy()/memset() alternatives mechanism x86-64: Modify copy_user_generic() alternatives mechanism x86: Lift restriction on the location of FIX_BTMAP_* x86, core: Optimize hweight32()
2010-02-25x86: Add support for lock prefix in alternativesLuca Barbieri1-2/+4
The current lock prefix UP/SMP alternative code doesn't allow LOCK_PREFIX to be used in alternatives code. This patch solves the problem by adding a new LOCK_PREFIX_ALTERNATIVE_PATCH macro that only records the lock prefix location but does not emit the prefix. The user of this macro can then start any alternative sequence with "lock" and have it UP/SMP patched. To make this work, the UP/SMP alternative code is changed to do the lock/DS prefix switching only if the byte actually contains a lock or DS prefix. Thus, if an alternative without the "lock" is selected, it will now do nothing instead of clobbering the code. Changes in v2: - Naming change - Change label to not conflict with alternatives Signed-off-by: Luca Barbieri <luca@luca-barbieri.com> LKML-Reference: <1267005265-27958-2-git-send-email-luca@luca-barbieri.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-25x86: Add text_poke_smp for SMP cross modifying codeMasami Hiramatsu1-0/+60
Add generic text_poke_smp for SMP which uses stop_machine() to synchronize modifying code. This stop_machine() method is officially described at "7.1.3 Handling Self- and Cross-Modifying Code" on the intel's software developer's manual 3A. Since stop_machine() can't protect code against NMI/MCE, this function can not modify those handlers. And also, this function is basically for modifying multibyte-single-instruction. For modifying multibyte-multi-instructions, we need another special trap & detour code. This code originaly comes from immediate values with stop_machine() version. Thanks Jason and Mathieu! Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Anders Kaseorg <andersk@ksplice.com> Cc: Tim Abbott <tabbott@ksplice.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> LKML-Reference: <20100225133438.6725.80273.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-07x86/alternatives: Fix build warningMasami Hiramatsu1-2/+4
Fixes these warnings: arch/x86/kernel/alternative.c: In function 'alternatives_text_reserved': arch/x86/kernel/alternative.c:402: warning: comparison of distinct pointer types lacks a cast arch/x86/kernel/alternative.c:402: warning: comparison of distinct pointer types lacks a cast arch/x86/kernel/alternative.c:405: warning: comparison of distinct pointer types lacks a cast arch/x86/kernel/alternative.c:405: warning: comparison of distinct pointer types lacks a cast Caused by: 2cfa197: ftrace/alternatives: Introducing *_text_reserved functions Changes in v2: - Use local variables to compare, instead of type casts. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20100205171647.15750.37221.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-04ftrace/alternatives: Introducing *_text_reserved functionsMasami Hiramatsu1-0/+16
Introducing *_text_reserved functions for checking the text address range is partially reserved or not. This patch provides checking routines for x86 smp alternatives and dynamic ftrace. Since both functions modify fixed pieces of kernel text, they should reserve and protect those from other dynamic text modifier, like kprobes. This will also be extended when introducing other subsystems which modify fixed pieces of kernel text. Dynamic text modifiers should avoid those. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: przemyslaw@pawelczyk.it Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <20100202214911.4694.16587.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-30x86-64: Modify copy_user_generic() alternatives mechanismJan Beulich1-1/+3
In order to avoid unnecessary chains of branches, rather than implementing copy_user_generic() as a function consisting of just a single (possibly patched) branch, instead properly deal with patching call instructions in the alternative instructions framework, and move the patching into the callers. As a follow-on, one could also introduce something like __EXPORT_SYMBOL_ALT() to avoid patching call sites in modules. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <4B2BB8180200007800026AE7@vpn.id2.novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-14Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tipLinus Torvalds1-1/+1
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits) x86: Fix code patching for paravirt-alternatives on 486 x86, msr: change msr-reg.o to obj-y, and export its symbols x86: Use hard_smp_processor_id() to get apic id for AMD K8 cpus x86, sched: Workaround broken sched domain creation for AMD Magny-Cours x86, mcheck: Use correct cpumask for shared bank4 x86, cacheinfo: Fixup L3 cache information for AMD multi-node processors x86: Fix CPU llc_shared_map information for AMD Magny-Cours x86, msr: Fix msr-reg.S compilation with gas 2.16.1, on 32-bit too x86: Move kernel_fpu_using to irq_fpu_usable in asm/i387.h x86, msr: fix msr-reg.S compilation with gas 2.16.1 x86, msr: Export the register-setting MSR functions via /dev/*/msr x86, msr: Create _on_cpu helpers for {rw,wr}msr_safe_regs() x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT x86, msr: CFI annotations, cleanups for msr-reg.S x86, asm: Make _ASM_EXTABLE() usable from assembly code x86, asm: Add 32-bit versions of the combined CFI macros x86, AMD: Disable wrongly set X86_FEATURE_LAHF_LM CPUID bit x86, msr: Rewrite AMD rd/wrmsr variants x86, msr: Add rd/wrmsr interfaces with preset registers x86: add specific support for Intel Atom architecture ...
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