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* mm/gup: Introduce get_user_pages_remote()Dave Hansen2016-02-1611-27/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For protection keys, we need to understand whether protections should be enforced in software or not. In general, we enforce protections when working on our own task, but not when on others. We call these "current" and "remote" operations. This patch introduces a new get_user_pages() variant: get_user_pages_remote() Which is a replacement for when get_user_pages() is called on non-current tsk/mm. We also introduce a new gup flag: FOLL_REMOTE which can be used for the "__" gup variants to get this new behavior. The uprobes is_trap_at_addr() location holds mmap_sem and calls get_user_pages(current->mm) on an instruction address. This makes it a pretty unique gup caller. Being an instruction access and also really originating from the kernel (vs. the app), I opted to consider this a 'remote' access where protection keys will not be enforced. Without protection keys, this patch should not change any behavior. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: jack@suse.cz Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210154.3F0E51EA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
*---. Merge branches 'x86/fpu', 'x86/mm' and 'x86/asm' into x86/pkeysIngo Molnar2016-02-1694-1001/+1129
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | Provide a stable basis for the pkeys patches, which touches various x86 details. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/cpufeature: Speed up cpu_feature_enabled()Borislav Petkov2016-02-161-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When GCC cannot do constant folding for this macro, it falls back to cpu_has(). But static_cpu_has() is optimal and it works at all times now. So use it and speedup the fallback case. Before we had this: mov 0x99d674(%rip),%rdx # ffffffff81b0d9f4 <boot_cpu_data+0x34> shr $0x2e,%rdx and $0x1,%edx jne ffffffff811704e9 <do_munmap+0x3f9> After alternatives patching, it turns into: jmp 0xffffffff81170390 nopl (%rax) ... callq ffffffff81056e00 <mpx_notify_unmap> ffffffff81170390: mov 0x170(%r12),%rdi Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Joerg Roedel <joro@8bytes.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1455578358-28347-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/mm: Honour passed pgprot in track_pfn_insert() and track_pfn_remap()Matthew Wilcox2016-02-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | track_pfn_insert() overwrites the pgprot that is passed in with a value based on the VMA's page_prot. This is a problem for people trying to do clever things with the new vm_insert_pfn_prot() as it will simply overwrite the passed protection flags. If we use the current value of the pgprot as the base, then it will behave as people are expecting. Also fix track_pfn_remap() in the same way. Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1453742717-10326-2-git-send-email-matthew.r.wilcox@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/asm/bitops: Force inlining of test_and_set_bit and friendsDenys Vlasenko2016-02-091-18/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes GCC mysteriously doesn't inline very small functions we expect to be inlined, see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 Arguably, GCC should do better, but GCC people aren't willing to invest time into it and are asking to use __always_inline instead. With this .config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os here's an example of functions getting deinlined many times: test_and_set_bit (166 copies, ~1260 calls) 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 48 0f ab 3e lock bts %rdi,(%rsi) 72 04 jb <test_and_set_bit+0xf> 31 c0 xor %eax,%eax eb 05 jmp <test_and_set_bit+0x14> b8 01 00 00 00 mov $0x1,%eax 5d pop %rbp c3 retq test_and_clear_bit (124 copies, ~1000 calls) 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 48 0f b3 3e lock btr %rdi,(%rsi) 72 04 jb <test_and_clear_bit+0xf> 31 c0 xor %eax,%eax eb 05 jmp <test_and_clear_bit+0x14> b8 01 00 00 00 mov $0x1,%eax 5d pop %rbp c3 retq change_bit (3 copies, 8 calls) 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 48 0f bb 3e lock btc %rdi,(%rsi) 5d pop %rbp c3 retq clear_bit_unlock (2 copies, 11 calls) 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 48 0f b3 3e lock btr %rdi,(%rsi) 5d pop %rbp c3 retq This patch works it around via s/inline/__always_inline/. Code size decrease by ~13.5k after the patch: text data bss dec filename 92110727 20826144 36417536 149354407 vmlinux.before 92097234 20826176 36417536 149340946 vmlinux.after Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Graf <tgraf@suug.ch> Link: http://lkml.kernel.org/r/1454881887-1367-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/entry/traps: Refactor preemption and interrupt flag handlingAlexander Kuleshov2016-02-011-28/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the preemption and interrupt flag handling more readable by removing preempt_conditional_sti() and preempt_conditional_cli() helpers and using preempt_disable() and preempt_enable_no_resched() instead. Rename contitional_sti() and conditional_cli() to the more understandable cond_local_irq_enable() and cond_local_irq_disable() respectively, while at it. Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> [ Boris: massage text. ] Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/1453750913-4781-2-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/syscalls/64: Mark sys_iopl() as using ptregsAndy Lutomirski2016-02-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sys_iopl() both reads and writes pt_regs->flags. Mark it as using ptregs. This isn't strictly necessary, as pt_regs->flags is available even in the fast path, but this is very lightweight now that we have syscall qualifiers and it could avoid some pain down the road. Reported-and-tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/3de0ca692fa8bf414c5e3d7afe3e6195d1a10e1f.1454261517.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/entry/64: Fix fast-path syscall return register stateAndy Lutomirski2016-02-011-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I was fishing RIP (i.e. RCX) out of pt_regs->cx and RFLAGS (i.e. R11) out of pt_regs->r11. While it usually worked (pt_regs started out with CX == IP and R11 == FLAGS), it was very fragile. In particular, it broke sys_iopl() because sys_iopl() forgot to mark itself as using ptregs. Undo that part of the syscall rework. There was no compelling reason to do it this way. While I'm at it, load RCX and R11 before the other regs to be a little friendlier to the CPU, as they will be the first of the reloaded registers to be used. Reported-and-tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 1e423bff959e x86/entry/64: ("Migrate the 64-bit syscall slow path to C") Link: http://lkml.kernel.org/r/a85f8360c397e48186a9bc3e565ad74307a7b011.1454261517.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/entry/64: Fix an IRQ state error on ptregs-using syscallsAndy Lutomirski2016-02-011-6/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I messed up the IRQ state when jumping off the fast path due to invocation of a ptregs-using syscall. This bug shouldn't have had any impact yet, but it would have caused problems with subsequent context tracking cleanups. Reported-and-tested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 1e423bff959e x86/entry/64: ("Migrate the 64-bit syscall slow path to C") Link: http://lkml.kernel.org/r/ab92cd365fb7b0a56869e920017790d96610fdca.1454261517.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/vdso: Use static_cpu_has()Borislav Petkov2016-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... and simplify and speed up a tad. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-10-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/alternatives: Discard dynamic check after initBrian Gerst2016-01-302-13/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the code to do the dynamic check to the altinstr_aux section so that it is discarded after alternatives have run and a static branch has been chosen. This way we're changing the dynamic branch from C code to assembly, which makes it *substantially* smaller while avoiding a completely unnecessary call to an out of line function. Signed-off-by: Brian Gerst <brgerst@gmail.com> [ Changed it to do TESTB, as hpa suggested. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kristen Carlson Accardi <kristen@linux.intel.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1452972124-7380-1-git-send-email-brgerst@gmail.com Link: http://lkml.kernel.org/r/20160127084525.GC30712@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/alternatives: Add an auxilary sectionBorislav Petkov2016-01-301-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add .altinstr_aux for additional instructions which will be used before and/or during patching. All stuff which needs more sophisticated patching should go there. See next patch. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/cpufeature: Get rid of the non-asm goto variantBorislav Petkov2016-01-301-44/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I can simply quote hpa from the mail: "Get rid of the non-asm goto variant and just fall back to dynamic if asm goto is unavailable. It doesn't make any sense, really, if it is supposed to be safe, and by now the asm goto-capable gcc is in more wide use. (Originally the gcc 3.x fallback to pure dynamic didn't exist, either.)" Booy, am I lazy. Cleanup the whole CC_HAVE_ASM_GOTO ifdeffery too, while at it. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160127084325.GB30712@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/cpufeature: Replace the old static_cpu_has() with safe variantBorislav Petkov2016-01-308-125/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So the old one didn't work properly before alternatives had run. And it was supposed to provide an optimized JMP because the assumption was that the offset it is jumping to is within a signed byte and thus a two-byte JMP. So I did an x86_64 allyesconfig build and dumped all possible sites where static_cpu_has() was used. The optimization amounted to all in all 12(!) places where static_cpu_has() had generated a 2-byte JMP. Which has saved us a whopping 36 bytes! This clearly is not worth the trouble so we can remove it. The only place where the optimization might count - in __switch_to() - we will handle differently. But that's not subject of this patch. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-6-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov2016-01-3050-328/+336
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * Merge branch 'x86/cpu' into x86/asm, to avoid conflictIngo Molnar2016-01-301-0/+1
| | | |\ | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | | * x86/cpufeature: Add AMD AVIC bitBorislav Petkov2016-01-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CPUID Fn8000_000A_EDX[13] denotes support for AMD's Virtual Interrupt controller, i.e., APIC virtualization. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Kaplan <david.kaplan@amd.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: http://lkml.kernel.org/r/1452938292-12327-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/entry/64: Migrate the 64-bit syscall slow path to CAndy Lutomirski2016-01-292-78/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is more complicated than the 32-bit and compat cases because it preserves an asm fast path for the case where the callee-saved regs aren't needed in pt_regs and no entry or exit work needs to be done. This appears to slow down fastpath syscalls by no more than one cycle on my Skylake laptop. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ce2335a4d42dc164b24132ee5e8c7716061f947b.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/entry/64: Stop using int_ret_from_sys_call in ret_from_forkAndy Lutomirski2016-01-291-16/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ret_from_fork is now open-coded and is no longer tangled up with the syscall code. This isn't so bad -- this adds very little code, and IMO the result is much easier to understand. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a0747e2a5e47084655a1e96351c545b755c41fa7.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/entry/64: Call all native slow-path syscalls with full pt-regsAndy Lutomirski2016-01-292-87/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This removes all of the remaining asm syscall stubs except for stub_ptregs_64. Entries in the main syscall table are now all callable from C. The resulting asm is every bit as ridiculous as it looks. The next few patches will clean it up. This patch is here to let reviewers rest their brains and for bisection. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a6b3801be0d505d50aefabda02d3b93efbfc9c73.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/entry/64: Always run ptregs-using syscalls on the slow pathAndy Lutomirski2016-01-293-24/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 64-bit syscalls currently have an optimization in which they are called with partial pt_regs. A small handful require full pt_regs. In the 32-bit and compat cases, I cleaned this up by forcing full pt_regs for all syscalls. The performance hit doesn't really matter as the affected system calls are fundamentally heavy and this is the 32-bit compat case. I want to clean up the 64-bit case as well, but I don't want to hurt fast path performance. To do that, I want to force the syscalls that use pt_regs onto the slow path. This will enable us to make slow path syscalls be real ABI-compliant C functions. Use the new syscall entry qualification machinery for this. 'stub_clone' is now 'stub_clone/ptregs'. The next patch will eliminate the stubs, and we'll just have 'sys_clone/ptregs'. As of this patch, two-phase entry tracing is no longer used. It has served its purpose (namely a huge speedup on some workloads prior to more general opportunistic SYSRET support), and once the dust settles I'll send patches to back it out. The implementation is heavily based on a patch from Brian Gerst: http://lkml.kernel.org/g/1449666173-15366-1-git-send-email-brgerst@gmail.com Originally-From: Brian Gerst <brgerst@gmail.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Frédéric Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/b9beda88460bcefec6e7d792bd44eca9b760b0c4.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/syscalls: Add syscall entry qualifiersAndy Lutomirski2016-01-298-16/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will let us specify something like 'sys_xyz/foo' instead of 'sys_xyz' in the syscall table, where the 'foo' qualifier conveys some extra information to the C code. The intent is to allow things like sys_execve/ptregs to indicate that sys_execve() touches pt_regs. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2de06e33dce62556b3ec662006fcb295504e296e.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/syscalls: Move compat syscall entry handling into syscalltbl.shAndy Lutomirski2016-01-298-23/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than duplicating the compat entry handling in all consumers of syscalls_BITS.h, handle it directly in syscalltbl.sh. Now we generate entries in syscalls_32.h like: __SYSCALL_I386(5, sys_open) __SYSCALL_I386(5, compat_sys_open) and all of its consumers implicitly get the right entry point. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/b7c2b501dc0e6e43050e916b95807c3e2e16e9bb.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/syscalls: Remove __SYSCALL_COMMON and __SYSCALL_X32Andy Lutomirski2016-01-295-20/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The common/64/x32 distinction has no effect other than determining which kernels actually support the syscall. Move the logic into syscalltbl.sh. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/58d4a95f40e43b894f93288b4a3633963d0ee22e.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | x86/syscalls: Refactor syscalltbl.shAndy Lutomirski2016-01-291-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This splits out the code to emit a syscall line. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1bfcbba991f5cfaa9291ff950a593daa972a205f.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | selftests/x86: Add check_initial_reg_state()Andy Lutomirski2016-01-292-1/+117
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This checks that ELF binaries are started with an appropriately blank register state. ( There's currently a nasty special case in the entry asm to arrange for this. I'm planning on removing the special case, and this will help make sure I don't break it. ) Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ef54f8d066b30a3eb36bbf26300eebb242185700.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | selftests/x86: Extend Makefile to allow 64-bit-only testsAndy Lutomirski2016-01-291-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously the Makefile supported 32-bit-only tests and tests that were 32-bit and 64-bit. This adds the support for tests that are only built as 64-bit binaries. There aren't any yet, but there might be a few some day. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shuah Khan <shuahkhan@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-api@vger.kernel.org Link: http://lkml.kernel.org/r/99789bfe65706e6df32cc7e13f656e8c9fa92031.1454022279.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | Merge tag 'v4.5-rc1' into x86/asm, to refresh the branch before merging new ↵Ingo Molnar2016-01-299775-402893/+723766
| | | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/asm: Remove unused L3_PAGE_OFFSETAlexander Kuleshov2016-01-271-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | L3_PAGE_OFFSET was introduced in commit a6523748bd (paravirt/x86, 64-bit: move __PAGE_OFFSET to leave a space for hypervisor), but has no users. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Link: http://lkml.kernel.org/r/1453810881-30622-1-git-send-email-kuleshovmail@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | | * | | x86/asm: Add C versions of frame pointer macrosJosh Poimboeuf2016-01-191-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add C versions of the frame pointer macros which can be used to create a stack frame in inline assembly. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f6786a282bf232ede3e2866414eae3cf02c7d662.1450442274.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/asm: Clean up frame pointer macrosJosh Poimboeuf2016-01-191-16/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The asm macros for setting up and restoring the frame pointer aren't currently being used. However, they will be needed soon to help asm functions to comply with stacktool. Rename FRAME/ENDFRAME to FRAME_BEGIN/FRAME_END for more symmetry. Also make the code more readable and improve the comments. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/3f488a8e3bfc8ac7d4d3d350953e664e7182b044.1450442274.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/signal: Cleanup get_nr_restart_syscall()Dmitry V. Levin2016-01-191-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Check for TS_COMPAT instead of TIF_IA32 to distinguish ia32 tasks from 64-bit tasks. Check for __X32_SYSCALL_BIT iff CONFIG_X86_X32_ABI is defined. Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Elvira Khabirova <lineprinter0@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160111145515.GB29007@altlinux.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/asm/entry: Remove unused SAVE_ALL/RESTORE_ALL macros for !CONFIG_x86_64Alexander Kuleshov2016-01-191-31/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SAVE_ALL and RESTORE_ALL macros for !CONFIG_X86_64 were introduced in commit: 1a338ac32 commit ('sched, x86: Optimize the preempt_schedule() call') ... and were used in the ___preempt_schedule() and ___preempt_schedule_context() functions from the arch/x86/kernel/preempt.S. But the arch/x86/kernel/preempt.S file was removed in the following commit: 0ad6e3c5 commit ('x86: Speed up ___preempt_schedule*() by using THUNK helpers') The ___preempt_schedule()/___preempt_schedule_context() functions were reimplemeted and do not use SAVE_ALL/RESTORE_ALL anymore. These macros have no users anymore, so we can remove them. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453126394-13717-1-git-send-email-kuleshovmail@gmail.com [ Improved the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/vdso: Disallow vvar access to vclock IO for never-used vclocksAndy Lutomirski2016-01-124-7/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It makes me uncomfortable that even modern systems grant every process direct read access to the HPET. While fixing this for real without regressing anything is a mess (unmapping the HPET is tricky because we don't adequately track all the mappings), we can do almost as well by tracking which vclocks have ever been used and only allowing pages associated with used vclocks to be faulted in. This will cause rogue programs that try to peek at the HPET to get SIGBUS instead on most systems. We can't restrict faults to vclock pages that are associated with the currently selected vclock due to a race: a process could start to access the HPET for the first time and race against a switch away from the HPET as the current clocksource. We can't segfault the process trying to peek at the HPET in this case, even though the process isn't going to do anything useful with the data. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/e79d06295625c02512277737ab55085a498ac5d8.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/vdso: Use ->fault() instead of remap_pfn_range() for the vvar mappingAndy Lutomirski2016-01-121-40/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is IMO much less ugly, and it also opens the door to disallowing unprivileged userspace HPET access on systems with usable TSCs. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c19c2909e5ee3c3d8742f916586676bb7c40345f.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/vdso: Use .fault for the vDSO text mappingAndy Lutomirski2016-01-123-17/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The old scheme for mapping the vDSO text is rather complicated. vdso2c generates a struct vm_special_mapping and a blank .pages array of the correct size for each vdso image. Init code in vdso/vma.c populates the .pages array for each vDSO image, and the mapping code selects the appropriate struct vm_special_mapping. With .fault, we can use a less roundabout approach: vdso_fault() just returns the appropriate page for the selected vDSO image. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f886954c186bafd74e1b967c8931d852ae199aa2.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | x86/vdso: Track each mm's loaded vDSO image as well as its baseAndy Lutomirski2016-01-122-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As we start to do more intelligent things with the vDSO at runtime (as opposed to just at mm initialization time), we'll need to know which vDSO is in use. In principle, we could guess based on the mm type, but that's over-complicated and error-prone. Instead, just track it in the mmu context. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c99ac48681bad709ca7ad5ee899d9042a3af6b00.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | mm: Add vm_insert_pfn_prot()Andy Lutomirski2016-01-122-2/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86 vvar vma contains pages with differing cacheability flags. x86 currently implements this by manually inserting all the ptes using (io_)remap_pfn_range when the vma is set up. x86 wants to move to using .fault with VM_FAULT_NOPAGE to set up the mappings as needed. The correct API to use to insert a pfn in .fault is vm_insert_pfn(), but vm_insert_pfn() can't override the vma's cache mode, and the HPET page in particular needs to be uncached despite the fact that the rest of the VMA is cached. Add vm_insert_pfn_prot() to support varying cacheability within the same non-COW VMA in a more sane manner. x86 could alternatively use multiple VMAs, but that's messy, would break CRIU, and would create unnecessary VMAs that would waste memory. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/d2938d1eb37be7a5e4f86182db646551f11e45aa.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | * | | mm: Add a vm_special_mapping.fault() methodAndy Lutomirski2016-01-122-7/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Requiring special mappings to give a list of struct pages is inflexible: it prevents sane use of IO memory in a special mapping, it's inefficient (it requires arch code to initialize a list of struct pages, and it requires the mm core to walk the entire list just to figure out how long it is), and it prevents arch code from doing anything fancy when a special mapping fault occurs. Add a .fault method as an alternative to filling in a .pages array. Looks-OK-to: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a26d1677c0bc7e774c33f469451a78ca31e9e6af.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm: Fix INVPCID asm constraintBorislav Petkov2016-02-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So we want to specify the dependency on both @pcid and @addr so that the compiler doesn't reorder accesses to them *before* the TLB flush. But for that to work, we need to express this properly in the inline asm and deref the whole desc array, not the pointer to it. See clwb() for an example. This fixes the build error on 32-bit: arch/x86/include/asm/tlbflush.h: In function ‘__invpcid’: arch/x86/include/asm/tlbflush.h:26:18: error: memory input 0 is not directly addressable which gcc4.7 caught but 5.x didn't. Which is strange. :-\ Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Michael Matz <matz@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/dmi: Switch dmi_remap() from ioremap() [uncached] to ioremap_cache()Andy Lutomirski2016-02-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DMI cacheability is very confused on x86. dmi_early_remap() uses early_ioremap(), which uses FIXMAP_PAGE_IO, which is __PAGE_KERNEL_IO, which is __PAGE_KERNEL, which is cached. Don't ask me why this makes any sense. dmi_remap() uses ioremap(), which requests an uncached mapping. However, on non-EFI systems, the DMI data generally lives between 0xf0000 and 0x100000, which is in the legacy ISA range, which triggers a special case in the PAT code that overrides the cache mode requested by ioremap() and forces a WB mapping. On a UEFI boot, however, the DMI table can live at any physical address. On my laptop, it's around 0x77dd0000. That's nowhere near the legacy ISA range, so the ioremap() implicit uncached type is honored and we end up with a UC- mapping. UC- is a very, very slow way to read from main memory, so dmi_walk() is likely to take much longer than necessary. Given that, even on UEFI, we do early cached DMI reads, it seems safe to just ask for cached access. Switch to ioremap_cache(). I haven't tried to benchmark this, but I'd guess it saves several milliseconds of boot time. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jean Delvare <jdelvare@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/3147c38e51f439f3c8911db34c7d4ab22d854915.1453791969.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm: If INVPCID is available, use it to flush global mappingsAndy Lutomirski2016-02-091-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On my Skylake laptop, INVPCID function 2 (flush absolutely everything) takes about 376ns, whereas saving flags, twiddling CR4.PGE to flush global mappings, and restoring flags takes about 539ns. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/ed0ef62581c0ea9c99b9bf6df726015e96d44743.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm: Add a 'noinvpcid' boot option to turn off INVPCIDAndy Lutomirski2016-02-092-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a chicken bit to turn off INVPCID in case something goes wrong. It's an early_param() because we do TLB flushes before we parse __setup() parameters. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/f586317ed1bc2b87aee652267e515b90051af385.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm: Add INVPCID helpersAndy Lutomirski2016-02-091-0/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds helpers for each of the four currently-specified INVPCID modes. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/8a62b23ad686888cee01da134c91409e22064db9.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/kasan: Write protect kasan zero shadowAndrey Ryabinin2016-02-091-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After kasan_init() executed, no one is allowed to write to kasan_zero_page, so write protect it. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1452516679-32040-3-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/kasan: Clear kasan_zero_page after TLB flushAndrey Ryabinin2016-02-091-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we clear kasan_zero_page before __flush_tlb_all(). This works with current implementation of native_flush_tlb[_global]() because it doesn't cause do any writes to kasan shadow memory. But any subtle change made in native_flush_tlb*() could break this. Also current code seems doesn't work for paravirt guests (lguest). Only after the TLB flush we can be sure that kasan_zero_page is not used as early shadow anymore (instrumented code will not write to it). So it should cleared it only after the TLB flush. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1452516679-32040-2-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm/numa: Check for failures in numa_clear_kernel_node_hotplug()Ingo Molnar2016-02-081-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | numa_clear_kernel_node_hotplug() uses memblock_set_node() without checking for failures. memblock_set_node() is a complex function that might extend the memblock array - which extension might fail - so check for this possibility. It's not supposed to happen (because realistically if we have so little memory that this fails then we likely won't be able to boot anyway), but do the check nevertheless. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Brad Spengler <spender@grsecurity.net> Cc: Chen Tang <imtangchen@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: PaX Team <pageexec@freemail.hu> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: y14sg1 <y14sg1@comcast.net> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | x86/mm/numa: Clean up numa_clear_kernel_node_hotplug()Ingo Molnar2016-02-081-23/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So we fixed an overflow bug in numa_clear_kernel_node_hotplug(): 2b54ab3c66d4 ("x86/mm/numa: Fix memory corruption on 32-bit NUMA kernels") ... and the bug was indirectly caused by poor coding style, such as using start/end local variables unnecessarily, which lost the physaddr_t type. So make the code more readable and try to fully comment all the thinking behind the logic. No change in functionality. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Brad Spengler <spender@grsecurity.net> Cc: Chen Tang <imtangchen@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: PaX Team <pageexec@freemail.hu> Cc: Taku Izumi <izumi.taku@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: y14sg1 <y14sg1@comcast.net> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | Merge branch 'x86/urgent' into x86/mm, to pick up dependent fixIngo Molnar2016-02-085352-132008/+350807
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | x86/mm: Make kmap_prot into a #defineAndy Lutomirski2016-01-202-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The value (once we initialize it) is a foregone conclusion. Make it a #define to save a tiny amount of text and data size and to make it more comprehensible. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/0850eb0213de9da88544ff7fae72dc6d06d2b441.1453239349.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-01 17:25:01 +0000