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2020-01-04x86/insn: Add some Intel instructions to the opcode mapAdrian Hunter1-6/+12
[ Upstream commit b980be189c9badba50634671e2303e92bf28e35a ] Add to the opcode map the following instructions: cldemote tpause umonitor umwait movdiri movdir64b enqcmd enqcmds encls enclu enclv pconfig wbnoinvd For information about the instructions, refer Intel SDM May 2019 (325462-070US) and Intel Architecture Instruction Set Extensions May 2019 (319433-037). The instruction decoding can be tested using the perf tools' "x86 instruction decoder - new instructions" test as folllows: $ perf test -v "new " 2>&1 | grep -i cldemote Decoded ok: 0f 1c 00 cldemote (%eax) Decoded ok: 0f 1c 05 78 56 34 12 cldemote 0x12345678 Decoded ok: 0f 1c 84 c8 78 56 34 12 cldemote 0x12345678(%eax,%ecx,8) Decoded ok: 0f 1c 00 cldemote (%rax) Decoded ok: 41 0f 1c 00 cldemote (%r8) Decoded ok: 0f 1c 04 25 78 56 34 12 cldemote 0x12345678 Decoded ok: 0f 1c 84 c8 78 56 34 12 cldemote 0x12345678(%rax,%rcx,8) Decoded ok: 41 0f 1c 84 c8 78 56 34 12 cldemote 0x12345678(%r8,%rcx,8) $ perf test -v "new " 2>&1 | grep -i tpause Decoded ok: 66 0f ae f3 tpause %ebx Decoded ok: 66 0f ae f3 tpause %ebx Decoded ok: 66 41 0f ae f0 tpause %r8d $ perf test -v "new " 2>&1 | grep -i umonitor Decoded ok: 67 f3 0f ae f0 umonitor %ax Decoded ok: f3 0f ae f0 umonitor %eax Decoded ok: 67 f3 0f ae f0 umonitor %eax Decoded ok: f3 0f ae f0 umonitor %rax Decoded ok: 67 f3 41 0f ae f0 umonitor %r8d $ perf test -v "new " 2>&1 | grep -i umwait Decoded ok: f2 0f ae f0 umwait %eax Decoded ok: f2 0f ae f0 umwait %eax Decoded ok: f2 41 0f ae f0 umwait %r8d $ perf test -v "new " 2>&1 | grep -i movdiri Decoded ok: 0f 38 f9 03 movdiri %eax,(%ebx) Decoded ok: 0f 38 f9 88 78 56 34 12 movdiri %ecx,0x12345678(%eax) Decoded ok: 48 0f 38 f9 03 movdiri %rax,(%rbx) Decoded ok: 48 0f 38 f9 88 78 56 34 12 movdiri %rcx,0x12345678(%rax) $ perf test -v "new " 2>&1 | grep -i movdir64b Decoded ok: 66 0f 38 f8 18 movdir64b (%eax),%ebx Decoded ok: 66 0f 38 f8 88 78 56 34 12 movdir64b 0x12345678(%eax),%ecx Decoded ok: 67 66 0f 38 f8 1c movdir64b (%si),%bx Decoded ok: 67 66 0f 38 f8 8c 34 12 movdir64b 0x1234(%si),%cx Decoded ok: 66 0f 38 f8 18 movdir64b (%rax),%rbx Decoded ok: 66 0f 38 f8 88 78 56 34 12 movdir64b 0x12345678(%rax),%rcx Decoded ok: 67 66 0f 38 f8 18 movdir64b (%eax),%ebx Decoded ok: 67 66 0f 38 f8 88 78 56 34 12 movdir64b 0x12345678(%eax),%ecx $ perf test -v "new " 2>&1 | grep -i enqcmd Decoded ok: f2 0f 38 f8 18 enqcmd (%eax),%ebx Decoded ok: f2 0f 38 f8 88 78 56 34 12 enqcmd 0x12345678(%eax),%ecx Decoded ok: 67 f2 0f 38 f8 1c enqcmd (%si),%bx Decoded ok: 67 f2 0f 38 f8 8c 34 12 enqcmd 0x1234(%si),%cx Decoded ok: f3 0f 38 f8 18 enqcmds (%eax),%ebx Decoded ok: f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%eax),%ecx Decoded ok: 67 f3 0f 38 f8 1c enqcmds (%si),%bx Decoded ok: 67 f3 0f 38 f8 8c 34 12 enqcmds 0x1234(%si),%cx Decoded ok: f2 0f 38 f8 18 enqcmd (%rax),%rbx Decoded ok: f2 0f 38 f8 88 78 56 34 12 enqcmd 0x12345678(%rax),%rcx Decoded ok: 67 f2 0f 38 f8 18 enqcmd (%eax),%ebx Decoded ok: 67 f2 0f 38 f8 88 78 56 34 12 enqcmd 0x12345678(%eax),%ecx Decoded ok: f3 0f 38 f8 18 enqcmds (%rax),%rbx Decoded ok: f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%rax),%rcx Decoded ok: 67 f3 0f 38 f8 18 enqcmds (%eax),%ebx Decoded ok: 67 f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%eax),%ecx $ perf test -v "new " 2>&1 | grep -i enqcmds Decoded ok: f3 0f 38 f8 18 enqcmds (%eax),%ebx Decoded ok: f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%eax),%ecx Decoded ok: 67 f3 0f 38 f8 1c enqcmds (%si),%bx Decoded ok: 67 f3 0f 38 f8 8c 34 12 enqcmds 0x1234(%si),%cx Decoded ok: f3 0f 38 f8 18 enqcmds (%rax),%rbx Decoded ok: f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%rax),%rcx Decoded ok: 67 f3 0f 38 f8 18 enqcmds (%eax),%ebx Decoded ok: 67 f3 0f 38 f8 88 78 56 34 12 enqcmds 0x12345678(%eax),%ecx $ perf test -v "new " 2>&1 | grep -i encls Decoded ok: 0f 01 cf encls Decoded ok: 0f 01 cf encls $ perf test -v "new " 2>&1 | grep -i enclu Decoded ok: 0f 01 d7 enclu Decoded ok: 0f 01 d7 enclu $ perf test -v "new " 2>&1 | grep -i enclv Decoded ok: 0f 01 c0 enclv Decoded ok: 0f 01 c0 enclv $ perf test -v "new " 2>&1 | grep -i pconfig Decoded ok: 0f 01 c5 pconfig Decoded ok: 0f 01 c5 pconfig $ perf test -v "new " 2>&1 | grep -i wbnoinvd Decoded ok: f3 0f 09 wbnoinvd Decoded ok: f3 0f 09 wbnoinvd Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Link: http://lore.kernel.org/lkml/20191115135447.6519-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-17x86/asm: Fix MWAITX C-state hint valueJanakarajan Natarajan1-2/+2
commit 454de1e7d970d6bc567686052329e4814842867c upstream. As per "AMD64 Architecture Programmer's Manual Volume 3: General-Purpose and System Instructions", MWAITX EAX[7:4]+1 specifies the optional hint of the optimized C-state. For C0 state, EAX[7:4] should be set to 0xf. Currently, a value of 0xf is set for EAX[3:0] instead of EAX[7:4]. Fix this by changing MWAITX_DISABLE_CSTATES from 0xf to 0xf0. This hasn't had any implications so far because setting reserved bits in EAX is simply ignored by the CPU. [ bp: Fixup comment in delay_mwaitx() and massage. ] Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "x86@kernel.org" <x86@kernel.org> Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20191007190011.4859-1-Janakarajan.Natarajan@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06x86/lib/cpu: Address missing prototypes warningValdis Klētnieks1-0/+1
[ Upstream commit 04f5bda84b0712d6f172556a7e8dca9ded5e73b9 ] When building with W=1, warnings about missing prototypes are emitted: CC arch/x86/lib/cpu.o arch/x86/lib/cpu.c:5:14: warning: no previous prototype for 'x86_family' [-Wmissing-prototypes] 5 | unsigned int x86_family(unsigned int sig) | ^~~~~~~~~~ arch/x86/lib/cpu.c:18:14: warning: no previous prototype for 'x86_model' [-Wmissing-prototypes] 18 | unsigned int x86_model(unsigned int sig) | ^~~~~~~~~ arch/x86/lib/cpu.c:33:14: warning: no previous prototype for 'x86_stepping' [-Wmissing-prototypes] 33 | unsigned int x86_stepping(unsigned int sig) | ^~~~~~~~~~~~ Add the proper include file so the prototypes are there. Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/42513.1565234837@turing-police Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-31x86/kaslr: Fix incorrect i8254 outb() parametersDaniel Drake1-2/+2
commit 7e6fc2f50a3197d0e82d1c0e86282976c9e6c8a4 upstream. The outb() function takes parameters value and port, in that order. Fix the parameters used in the kalsr i8254 fallback code. Fixes: 5bfce5ef55cb ("x86, kaslr: Provide randomness functions") Signed-off-by: Daniel Drake <drake@endlessm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: hpa@zytor.com Cc: linux@endlessm.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190107034024.15005-1-drake@endlessm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-05objtool, x86: Add several functions and files to the objtool whitelistJosh Poimboeuf1-4/+4
commit c207aee48037abca71c669cbec407b9891965c34 upstream. In preparation for an objtool rewrite which will have broader checks, whitelist functions and files which cause problems because they do unusual things with the stack. These whitelists serve as a TODO list for which functions and files don't yet have undwarf unwinder coverage. Eventually most of the whitelists can be removed in favor of manual CFI hint annotations or objtool improvements. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/7f934a5d707a574bda33ea282e9478e627fb1829.1498659915.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13x86/mm/kaslr: Use the _ASM_MUL macro for multiplication to work around Clang ↵Matthias Kaehlcke1-1/+2
incompatibility [ Upstream commit 121843eb02a6e2fa30aefab64bfe183c97230c75 ] The constraint "rm" allows the compiler to put mix_const into memory. When the input operand is a memory location then MUL needs an operand size suffix, since Clang can't infer the multiplication width from the operand. Add and use the _ASM_MUL macro which determines the operand size and resolves to the NUL instruction with the corresponding suffix. This fixes the following error when building with clang: CC arch/x86/lib/kaslr.o /tmp/kaslr-dfe1ad.s: Assembler messages: /tmp/kaslr-dfe1ad.s:182: Error: no instruction mnemonic suffix given and no register operands; can't size instruction Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Cc: Grant Grundler <grundler@chromium.org> Cc: Greg Hackmann <ghackmann@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Davidson <md@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170501224741.133938-1-mka@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13x86/asm: Don't use RBP as a temporary register in csum_partial_copy_generic()Josh Poimboeuf1-6/+6
[ Upstream commit 42fc6c6cb1662ba2fa727dd01c9473c63be4e3b6 ] Andrey Konovalov reported the following warning while fuzzing the kernel with syzkaller: WARNING: kernel stack regs at ffff8800686869f8 in a.out:4933 has bad 'bp' value c3fc855a10167ec0 The unwinder dump revealed that RBP had a bad value when an interrupt occurred in csum_partial_copy_generic(). That function saves RBP on the stack and then overwrites it, using it as a scratch register. That's problematic because it breaks stack traces if an interrupt occurs in the middle of the function. Replace the usage of RBP with another callee-saved register (R15) so stack traces are no longer affected. Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: linux-sctp@vger.kernel.org Cc: netdev <netdev@vger.kernel.org> Cc: syzkaller <syzkaller@googlegroups.com> Link: http://lkml.kernel.org/r/4b03a961efda5ec9bfe46b7b9c9ad72d1efad343.1493909486.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-18Revert "x86/retpoline: Simplify vmexit_fill_RSB()"David Woodhouse2-57/+0
commit d1c99108af3c5992640aa2afa7d2e88c3775c06e upstream. This reverts commit 1dde7415e99933bb7293d6b2843752cbdb43ec11. By putting the RSB filling out of line and calling it, we waste one RSB slot for returning from the function itself, which means one fewer actual function call we can make if we're doing the Skylake abomination of call-depth counting. It also changed the number of RSB stuffings we do on vmexit from 32, which was correct, to 16. Let's just stop with the bikeshedding; it didn't actually *fix* anything anyway. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: arjan.van.de.ven@intel.com Cc: bp@alien8.de Cc: dave.hansen@intel.com Cc: jmattson@google.com Cc: karahmed@amazon.de Cc: kvm@vger.kernel.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/1519037457-7643-4-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_steppingJia Zhang1-1/+1
commit b399151cb48db30ad1e0e93dd40d68c6d007b637 upstream. x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com> [ Updated it to more recent kernels. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13x86/get_user: Use pointer masking to limit speculationDan Williams1-0/+10
(cherry picked from commit c7f631cb07e7da06ac1d231ca178452339e32a94) Quoting Linus: I do think that it would be a good idea to very expressly document the fact that it's not that the user access itself is unsafe. I do agree that things like "get_user()" want to be protected, but not because of any direct bugs or problems with get_user() and friends, but simply because get_user() is an excellent source of a pointer that is obviously controlled from a potentially attacking user space. So it's a prime candidate for then finding _subsequent_ accesses that can then be used to perturb the cache. Unlike the __get_user() case get_user() includes the address limit check near the pointer de-reference. With that locality the speculation can be mitigated with pointer narrowing rather than a barrier, i.e. array_index_nospec(). Where the narrowing is performed by: cmp %limit, %ptr sbb %mask, %mask and %mask, %ptr With respect to speculation the value of %ptr is either less than %limit or NULL. Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727417469.33451.11804043010080838495.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospecDan Williams1-2/+2
(cherry picked from commit 304ec1b050310548db33063e567123fae8fd0301) Quoting Linus: I do think that it would be a good idea to very expressly document the fact that it's not that the user access itself is unsafe. I do agree that things like "get_user()" want to be protected, but not because of any direct bugs or problems with get_user() and friends, but simply because get_user() is an excellent source of a pointer that is obviously controlled from a potentially attacking user space. So it's a prime candidate for then finding _subsequent_ accesses that can then be used to perturb the cache. __uaccess_begin_nospec() covers __get_user() and copy_from_iter() where the limit check is far away from the user pointer de-reference. In those cases a barrier_nospec() prevents speculation with a potential pointer to privileged memory. uaccess_try_nospec covers get_user_try. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727416953.33451.10508284228526170604.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}Dan Williams1-4/+4
(cherry picked from commit b5c4ae4f35325d520b230bab6eb3310613b72ac1) In preparation for converting some __uaccess_begin() instances to __uacess_begin_nospec(), make sure all 'from user' uaccess paths are using the _begin(), _end() helpers rather than open-coded stac() and clac(). No functional changes. Suggested-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Kees Cook <keescook@chromium.org> Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727416438.33451.17309465232057176966.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13x86/retpoline: Simplify vmexit_fill_RSB()Borislav Petkov2-0/+57
(cherry picked from commit 1dde7415e99933bb7293d6b2843752cbdb43ec11) Simplify it to call an asm-function instead of pasting 41 insn bytes at every call site. Also, add alignment to the macro as suggested here: https://support.google.com/faqs/answer/7625886 [dwmw2: Clean up comments, let it clobber %ebx and just tell the compiler] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: dave.hansen@intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: peterz@infradead.org Cc: bp@alien8.de Cc: pbonzini@redhat.com Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1517070274-12128-3-git-send-email-dwmw@amazon.co.uk Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13x86/retpoline: Remove the esp/rsp thunkWaiman Long1-1/+0
(cherry picked from commit 1df37383a8aeabb9b418698f0bcdffea01f4b1b2) It doesn't make sense to have an indirect call thunk with esp/rsp as retpoline code won't work correctly with the stack pointer register. Removing it will help compiler writers to catch error in case such a thunk call is emitted incorrectly. Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support") Suggested-by: Jeff Law <law@redhat.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Kees Cook <keescook@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1516658974-27852-1-git-send-email-longman@redhat.com Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31Prevent timer value 0 for MWAITXJanakarajan Natarajan1-0/+7
commit 88d879d29f9cc0de2d930b584285638cdada6625 upstream. Newer hardware has uncovered a bug in the software implementation of using MWAITX for the delay function. A value of 0 for the timer is meant to indicate that a timeout will not be used to exit MWAITX. On newer hardware this can result in MWAITX never returning, resulting in NMI soft lockup messages being printed. On older hardware, some of the other conditions under which MWAITX can exit masked this issue. The AMD APM does not currently document this and will be updated. Please refer to http://marc.info/?l=kvm&m=148950623231140 for information regarding NMI soft lockup messages on an AMD Ryzen 1800X. This has been root-caused as a 0 passed to MWAITX causing it to wait indefinitely. This change has the added benefit of avoiding the unnecessary setup of MONITORX/MWAITX when the delay value is zero. Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Link: http://lkml.kernel.org/r/1493156643-29366-1-git-send-email-Janakarajan.Natarajan@amd.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-23kprobes/x86: Blacklist indirect thunk functions for kprobesMasami Hiramatsu1-1/+2
commit c1804a236894ecc942da7dc6c5abe209e56cba93 upstream. Mark __x86_indirect_thunk_* functions as blacklist for kprobes because those functions can be called from anywhere in the kernel including blacklist functions of kprobes. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Link: https://lkml.kernel.org/r/151629209111.10241.5444852823378068683.stgit@devbox Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-23retpoline: Introduce start/end markers of indirect thunkMasami Hiramatsu1-1/+1
commit 736e80a4213e9bbce40a7c050337047128b472ac upstream. Introduce start/end markers of __x86_indirect_thunk_* functions. To make it easy, consolidate .text.__x86.indirect_thunk.* sections to one .text.__x86.indirect_thunk section and put it in the end of kernel text section and adds __indirect_thunk_start/end so that other subsystem (e.g. kprobes) can identify it. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Woodhouse <dwmw@amazon.co.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17x86/retpoline/checksum32: Convert assembler indirect jumpsDavid Woodhouse1-3/+4
commit 5096732f6f695001fa2d6f1335a2680b37912c69 upstream. Convert all indirect jumps in 32bit checksum assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-11-git-send-email-dwmw@amazon.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17x86/retpoline: Add initial retpoline supportDavid Woodhouse2-0/+49
commit 76b043848fd22dbf7f8bf3a1452f8c70d557b860 upstream. Enable the use of -mindirect-branch=thunk-extern in newer GCC, and provide the corresponding thunks. Provide assembler macros for invoking the thunks in the same way that GCC does, from native and inline assembler. This adds X86_FEATURE_RETPOLINE and sets it by default on all CPUs. In some circumstances, IBRS microcode features may be used instead, and the retpoline can be disabled. On AMD CPUs if lfence is serialising, the retpoline can be dramatically simplified to a simple "lfence; jmp *\reg". A future patch, after it has been verified that lfence really is serialising in all circumstances, can enable this by setting the X86_FEATURE_RETPOLINE_AMD feature bit in addition to X86_FEATURE_RETPOLINE. Do not align the retpoline in the altinstr section, because there is no guarantee that it stays aligned when it's copied over the oldinstr during alternative patching. [ Andi Kleen: Rename the macros, add CONFIG_RETPOLINE option, export thunks] [ tglx: Put actual function CALL/JMP in front of the macros, convert to symbolic labels ] [ dwmw2: Convert back to numeric labels, merge objtool fixes ] Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-4-git-send-email-dwmw@amazon.co.uk Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-05x86/boot: Add early cmdline parsing for options with argumentsTom Lendacky1-0/+105
commit e505371dd83963caae1a37ead9524e8d997341be upstream. Add a cmdline_find_option() function to look for cmdline options that take arguments. The argument is returned in a supplied buffer and the argument length (regardless of whether it fits in the supplied buffer) is returned, with -1 indicating not found. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Larry Woodman <lwoodman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Toshimitsu Kani <toshi.kani@hpe.com> Cc: kasan-dev@googlegroups.com Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/36b5f97492a9745dce27682305f990fc20e5cf8a.1500319216.git.thomas.lendacky@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30x86/decoder: Add new TEST instruction patternMasami Hiramatsu1-1/+1
commit 12a78d43de767eaf8fb272facb7a7b6f2dc6a9df upstream. The kbuild test robot reported this build warning: Warning: arch/x86/tools/test_get_len found difference at <jump_table>:ffffffff8103dd2c Warning: ffffffff8103dd82: f6 09 d8 testb $0xd8,(%rcx) Warning: objdump says 3 bytes, but insn_get_length() says 2 Warning: decoded and checked 1569014 instructions with 1 warnings This sequence seems to be a new instruction not in the opcode map in the Intel SDM. The instruction sequence is "F6 09 d8", means Group3(F6), MOD(00)REG(001)RM(001), and 0xd8. Intel SDM vol2 A.4 Table A-6 said the table index in the group is "Encoding of Bits 5,4,3 of the ModR/M Byte (bits 2,1,0 in parenthesis)" In that table, opcodes listed by the index REG bits as: 000 001 010 011 100 101 110 111 TEST Ib/Iz,(undefined),NOT,NEG,MUL AL/rAX,IMUL AL/rAX,DIV AL/rAX,IDIV AL/rAX So, it seems TEST Ib is assigned to 001. Add the new pattern. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-12x86/uaccess: Optimize copy_user_enhanced_fast_string() for short stringsPaolo Abeni1-2/+5
commit 236222d39347e0e486010f10c1493e83dbbdfba8 upstream. According to the Intel datasheet, the REP MOVSB instruction exposes a pretty heavy setup cost (50 ticks), which hurts short string copy operations. This change tries to avoid this cost by calling the explicit loop available in the unrolled code for strings shorter than 64 bytes. The 64 bytes cutoff value is arbitrary from the code logic point of view - it has been selected based on measurements, as the largest value that still ensures a measurable gain. Micro benchmarks of the __copy_from_user() function with lengths in the [0-63] range show this performance gain (shorter the string, larger the gain): - in the [55%-4%] range on Intel Xeon(R) CPU E5-2690 v4 - in the [72%-9%] range on Intel Core i7-4810MQ Other tested CPUs - namely Intel Atom S1260 and AMD Opteron 8216 - show no difference, because they do not expose the ERMS feature bit. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> 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: H. Peter Anvin <hpa@zytor.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4533a1d101fd460f80e21329a34928fad521c1d4.1498744345.git.pabeni@redhat.com [ Clarified the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
2017-04-08x86/mce: Fix copy/paste error in exception table entriesTony Luck1-1/+1
commit 26a37ab319a26d330bab298770d692bb9c852aff upstream. Back in commit: 92b0729c34cab ("x86/mm, x86/mce: Add memcpy_mcsafe()") ... I made a copy/paste error setting up the exception table entries and ended up with two for label .L_cache_w3 and none for .L_cache_w2. This means that if we take a machine check on: .L_cache_w2: movq 2*8(%rsi), %r10 then we don't have an exception table entry for this instruction and we can't recover. Fix: s/3/2/ Signed-off-by: Tony Luck <tony.luck@intel.com> 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: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 92b0729c34cab ("x86/mm, x86/mce: Add memcpy_mcsafe()") Link: http://lkml.kernel.org/r/1490046030-25862-1-git-send-email-tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-15Merge branch 'kbuild' of ↵Linus Torvalds13-1/+43
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...
2016-09-05x86/mce: Improve memcpy_mcsafe()Tony Luck1-3/+3
Use the mcsafe_key defined in the previous patch to make decisions on which copy function to use. We can't use the FEATURE bit any more because PCI quirks run too late to affect the patching of code. So we use a static key. Turn memcpy_mcsafe() into an inline function to make life easier for callers. The assembly code that actually does the copy is now named memcpy_mcsafe_unrolled() Signed-off-by: Tony Luck <tony.luck@intel.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Boris Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/bfde2fc774e94f53d91b70a4321c85a0d33e7118.1472754712.git.tony.luck@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-08-11x86/mm/kaslr: Fix -Wformat-security warningNicolas Iooss1-1/+1
debug_putstr() is used to output strings without using printf-like formatting but debug_putstr(v) is defined as early_printk(v) in arch/x86/lib/kaslr.c. This makes clang reports the following warning when building with -Wformat-security: arch/x86/lib/kaslr.c:57:15: warning: format string is not a string literal (potentially insecure) [-Wformat-security] debug_putstr(purpose); ^~~~~~~ Fix this by using "%s" in early_printk(). Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Acked-by: Kees Cook <keescook@chromium.org> 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: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@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/20160806102039.27221-1-nicolas.iooss_linux@m4x.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-08x86/hweight: Don't clobber %rdiVille Syrjälä1-0/+2
The caller expects %rdi to remain intact, push+pop it make that happen. Fixes the following kind of explosions on my core2duo machine when trying to reboot or shut down: general protection fault: 0000 [#1] PREEMPT SMP Modules linked in: i915 i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea drm netconsole configfs binfmt_misc iTCO_wdt psmouse pcspkr snd_hda_codec_idt e100 coretemp hwmon snd_hda_codec_generic i2c_i801 mii i2c_smbus lpc_ich mfd_core snd_hda_intel uhci_hcd snd_hda_codec snd_hwdep snd_hda_core ehci_pci 8250 ehci_hcd snd_pcm 8250_base usbcore evdev serial_core usb_common parport_pc parport snd_timer snd soundcore CPU: 0 PID: 3070 Comm: reboot Not tainted 4.8.0-rc1-perf-dirty #69 Hardware name: /D946GZIS, BIOS TS94610J.86A.0087.2007.1107.1049 11/07/2007 task: ffff88012a0b4080 task.stack: ffff880123850000 RIP: 0010:[<ffffffff81003c92>] [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0 RSP: 0018:ffff880123853b60 EFLAGS: 00010087 RAX: 0000000000000001 RBX: ffff88012fc0a3c0 RCX: 000000000000001e RDX: 0000000000000000 RSI: 0000000040000000 RDI: ffff88012b014800 RBP: ffff880123853b88 R08: ffffffffffffffff R09: 0000000000000000 R10: ffffea0004a012c0 R11: ffffea0004acedc0 R12: ffffffff80000001 R13: ffff88012b0149c0 R14: ffff88012b014800 R15: 0000000000000018 FS: 00007f8b155cd700(0000) GS:ffff88012fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8b155f5000 CR3: 000000012a2d7000 CR4: 00000000000006f0 Stack: ffff88012fc0a3c0 ffff88012b014800 0000000000000004 0000000000000001 ffff88012fc1b750 ffff880123853bb0 ffffffff81003d59 ffff88012b014800 ffff88012fc0a3c0 ffff88012b014800 ffff880123853bd8 ffffffff81003e13 Call Trace: [<ffffffff81003d59>] x86_pmu_stop+0x59/0xd0 [<ffffffff81003e13>] x86_pmu_del+0x43/0x140 [<ffffffff8111705d>] event_sched_out.isra.105+0xbd/0x260 [<ffffffff8111738d>] __perf_remove_from_context+0x2d/0xb0 [<ffffffff8111745d>] __perf_event_exit_context+0x4d/0x70 [<ffffffff810c8826>] generic_exec_single+0xb6/0x140 [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0 [<ffffffff81117410>] ? __perf_remove_from_context+0xb0/0xb0 [<ffffffff810c898f>] smp_call_function_single+0xdf/0x140 [<ffffffff81113d27>] perf_event_exit_cpu_context+0x87/0xc0 [<ffffffff81113d73>] perf_reboot+0x13/0x40 [<ffffffff8107578a>] notifier_call_chain+0x4a/0x70 [<ffffffff81075ad7>] __blocking_notifier_call_chain+0x47/0x60 [<ffffffff81075b06>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff81076a1d>] kernel_restart_prepare+0x1d/0x40 [<ffffffff81076ae2>] kernel_restart+0x12/0x60 [<ffffffff81076d56>] SYSC_reboot+0xf6/0x1b0 [<ffffffff811a823c>] ? mntput_no_expire+0x2c/0x1b0 [<ffffffff811a83e4>] ? mntput+0x24/0x40 [<ffffffff811894fc>] ? __fput+0x16c/0x1e0 [<ffffffff811895ae>] ? ____fput+0xe/0x10 [<ffffffff81072fc3>] ? task_work_run+0x83/0xa0 [<ffffffff81001623>] ? exit_to_usermode_loop+0x53/0xc0 [<ffffffff8100105a>] ? trace_hardirqs_on_thunk+0x1a/0x1c [<ffffffff81076e6e>] SyS_reboot+0xe/0x10 [<ffffffff814c4ba5>] entry_SYSCALL_64_fastpath+0x18/0xa3 Code: 7c 4c 8d af c0 01 00 00 49 89 fe eb 10 48 09 c2 4c 89 e0 49 0f b1 55 00 4c 39 e0 74 35 4d 8b a6 c0 01 00 00 41 8b 8e 60 01 00 00 <0f> 33 8b 35 6e 02 8c 00 48 c1 e2 20 85 f6 7e d2 48 89 d3 89 cf RIP [<ffffffff81003c92>] x86_perf_event_update+0x52/0xc0 RSP <ffff880123853b60> ---[ end trace 7ec95181faf211be ]--- note: reboot[3070] exited with preempt_count 2 Cc: Borislav Petkov <bp@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Fixes: f5967101e9de ("x86/hweight: Get rid of the special calling convention") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-08x86: move exports to actual definitionsAl Viro13-1/+43
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-08-01Merge branch 'x86-headers-for-linus' of ↵Linus Torvalds14-14/+16
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 header cleanups from Ingo Molnar: "This tree is a cleanup of the x86 tree reducing spurious uses of module.h - which should improve build performance a bit" * 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, crypto: Restore MODULE_LICENSE() to glue_helper.c so it loads x86/apic: Remove duplicated include from probe_64.c x86/ce4100: Remove duplicated include from ce4100.c x86/headers: Include spinlock_types.h in x8664_ksyms_64.c for missing spinlock_t x86/platform: Delete extraneous MODULE_* tags fromm ts5500 x86: Audit and remove any remaining unnecessary uses of module.h x86/kvm: Audit and remove any unnecessary uses of module.h x86/xen: Audit and remove any unnecessary uses of module.h x86/platform: Audit and remove any unnecessary uses of module.h x86/lib: Audit and remove any unnecessary uses of module.h x86/kernel: Audit and remove any unnecessary uses of module.h x86/mm: Audit and remove any unnecessary uses of module.h x86: Don't use module.h just for AUTHOR / LICENSE tags
2016-07-29Merge tag 'libnvdimm-for-4.8' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: - Replace pcommit with ADR / directed-flushing. The pcommit instruction, which has not shipped on any product, is deprecated. Instead, the requirement is that platforms implement either ADR, or provide one or more flush addresses per nvdimm. ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers to the memory controller on a power-fail event. Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure: "Flush Hint Address Structure". A flush hint is an mmio address that when written and fenced assures that all previous posted writes targeting a given dimm have been flushed to media. - On-demand ARS (address range scrub). Linux uses the results of the ACPI ARS commands to track bad blocks in pmem devices. When latent errors are detected we re-scrub the media to refresh the bad block list, userspace can also request a re-scrub at any time. - Support for the Microsoft DSM (device specific method) command format. - Support for EDK2/OVMF virtual disk device memory ranges. - Various fixes and cleanups across the subsystem. * tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits) libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register" nfit: do an ARS scrub on hitting a latent media error nfit: move to nfit/ sub-directory nfit, libnvdimm: allow an ARS scrub to be triggered on demand libnvdimm: register nvdimm_bus devices with an nd_bus driver pmem: clarify a debug print in pmem_clear_poison x86/insn: remove pcommit Revert "KVM: x86: add pcommit support" nfit, tools/testing/nvdimm/: unify shutdown paths libnvdimm: move ->module to struct nvdimm_bus_descriptor nfit: cleanup acpi_nfit_init calling convention nfit: fix _FIT evaluation memory leak + use after free tools/testing/nvdimm: add manufacturing_{date|location} dimm properties tools/testing/nvdimm: add virtual ramdisk range acpi, nfit: treat virtual ramdisk SPA as pmem region pmem: kill __pmem address space pmem: kill wmb_pmem() libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes fs/dax: remove wmb_pmem() libnvdimm, pmem: flush posted-write queues on shutdown ...
2016-07-26Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2-95/+186
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "This tree contains tooling fixes plus some additions: - fixes to the vdso2c build environment that Stephen Rothwell is using for the linux-next build (Arnaldo Carvalho de Melo) - AVX-512 instruction mappings (Adrian Hunter) - misc fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "perf tools: event.h needs asm/perf_regs.h" x86: Make the vdso2c compiler use the host architecture headers tools build: Fix objtool build with ARCH=x86_64 objtool: Always use host headers objtool: Use tools/scripts/Makefile.arch to get ARCH and HOSTARCH tools build: Add HOSTARCH Makefile variable perf tests kmod-path: Fix build on ubuntu:16.04-x-armhf perf tools: Add AVX-512 instructions to the new instructions test perf tools: Add AVX-512 support to the instruction decoder used by Intel PT x86/insn: Add AVX-512 support to the instruction decoder x86/insn: perf tools: Fix vcvtph2ps instruction decoding
2016-07-26Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds2-0/+91
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "The main changes: - add initial commits to randomize kernel memory section virtual addresses, enabled via a new kernel option: RANDOMIZE_MEMORY (Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu) - enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees Cook) - EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar) - misc cleanups/fixes" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Simplify EBDA-vs-BIOS reservation logic x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does x86/boot: Reorganize and clean up the BIOS area reservation code x86/mm: Do not reference phys addr beyond kernel x86/mm: Add memory hotplug support for KASLR memory randomization x86/mm: Enable KASLR for vmalloc memory regions x86/mm: Enable KASLR for physical mapping memory regions x86/mm: Implement ASLR for kernel memory regions x86/mm: Separate variable for trampoline PGD x86/mm: Add PUD VA support for physical mapping x86/mm: Update physical mapping variable names x86/mm: Refactor KASLR entropy functions x86/KASLR: Fix boot crash with certain memory configurations x86/boot/64: Add forgotten end of function marker x86/KASLR: Allow randomization below the load address x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G x86/KASLR: Randomize virtual address separately x86/KASLR: Clarify identity map interface x86/boot: Refuse to build with data relocations x86/KASLR, x86/power: Remove x86 hibernation restrictions
2016-07-23x86/insn: remove pcommitDan Williams1-1/+1
The pcommit instruction is being deprecated in favor of either ADR (asynchronous DRAM refresh: flush-on-power-fail) at the platform level, or posted-write-queue flush addresses as defined by the ACPI 6.x NFIT (NVDIMM Firmware Interface Table). Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-21x86/insn: Add AVX-512 support to the instruction decoderAdrian Hunter2-95/+186
Add support for Intel's AVX-512 instructions to the instruction decoder. AVX-512 instructions are documented in Intel Architecture Instruction Set Extensions Programming Reference (February 2016). AVX-512 instructions are identified by a EVEX prefix which, for the purpose of instruction decoding, can be treated as though it were a 4-byte VEX prefix. Existing instructions which can now accept an EVEX prefix need not be further annotated in the op code map (x86-opcode-map.txt). In the case of new instructions, the op code map is updated accordingly. Also add associated Mask Instructions that are used to manipulate mask registers used in AVX-512 instructions. The 'perf tools' instruction decoder is updated in a subsequent patch. And a representative set of instructions is added to the perf tools new instructions test in a subsequent patch. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dan Williams <dan.j.williams@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: X86 ML <x86@kernel.org> Link: http://lkml.kernel.org/r/1469003437-32706-3-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-20x86/insn: perf tools: Fix vcvtph2ps instruction decodingAdrian Hunter1-1/+1
vcvtph2ps does not have an immediate operand, so remove the erroneous 'Ib' from its opcode map entry. Add vcvtph2ps to the perf tools new instructions test to verify it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dan Williams <dan.j.williams@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: X86 ML <x86@kernel.org> Link: http://lkml.kernel.org/r/1469003437-32706-2-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-15x86/uaccess: Move thread_info::addr_limit to thread_structAndy Lutomirski5-20/+21
struct thread_info is a legacy mess. To prepare for its partial removal, move thread_info::addr_limit out. As an added benefit, this way is simpler. Signed-off-by: Andy Lutomirski <luto@kernel.org> 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: Josh Poimboeuf <jpoimboe@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/15bee834d09402b47ac86f2feccdf6529f9bc5b0.1468527351.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14x86/lib: Audit and remove any unnecessary uses of module.hPaul Gortmaker14-14/+16
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance for the presence of either and replace as needed. Build testing revealed a couple implicit header usage issues that were fixed. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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/20160714001901.31603-5-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08x86/mm: Refactor KASLR entropy functionsThomas Garnier2-0/+91
Move the KASLR entropy functions into arch/x86/lib to be used in early kernel boot for KASLR memory randomization. Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: Alexander Popov <alpopov@ptsecurity.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Baoquan He <bhe@redhat.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: kernel-hardening@lists.openwall.com Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/1466556426-32664-2-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08x86/hweight: Get rid of the special calling conventionBorislav Petkov2-1/+78
People complained about ARCH_HWEIGHT_CFLAGS and how it throws a wrench into kcov, lto, etc, experimentations. Add asm versions for __sw_hweight{32,64}() and do explicit saving and restoring of clobbered registers. This gets rid of the special calling convention. We get to call those functions on !X86_FEATURE_POPCNT CPUs. We still need to hardcode POPCNT and register operands as some old gas versions which we support, do not know about POPCNT. Btw, remove redundant REX prefix from 32-bit POPCNT because alternatives can do padding now. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1464605787-20603-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-17Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - MSR access API fixes and enhancements (Andy Lutomirski) - early exception handling improvements (Andy Lutomirski) - user-space FS/GS prctl usage fixes and improvements (Andy Lutomirski) - Remove the cpu_has_*() APIs and replace them with equivalents (Borislav Petkov) - task switch micro-optimization (Brian Gerst) - 32-bit entry code simplification (Denys Vlasenko) - enhance PAT handling in enumated CPUs (Toshi Kani) ... and lots of other cleanups/fixlets" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GS x86/entry/32: Remove asmlinkage_protect() x86/entry/32: Remove GET_THREAD_INFO() from entry code x86/entry, sched/x86: Don't save/restore EFLAGS on task switch x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment x86/tls: Synchronize segment registers in set_thread_area() x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimization x86/segments/64: When load_gs_index fails, clear the base x86/segments/64: When loadsegment(fs, ...) fails, clear the base x86/asm: Make asm/alternative.h safe from assembly x86/asm: Stop depending on ptrace.h in alternative.h x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall() x86/asm: Make sure verify_cpu() has a good stack x86/extable: Add a comment about early exception handlers x86/msr: Set the return value to zero when native_rdmsr_safe() fails x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y x86/paravirt: Add paravirt_{read,write}_msr() x86/msr: Carry on after a non-"safe" MSR access fails ...
2016-05-16locking/rwsem: Fix comment on register clobberingBorislav Petkov1-2/+4
Document explicitly that %edx can get clobbered on the slow path, on 32-bit kernels. Something I learned the hard way. :-\ Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-next@vger.kernel.org Link: http://lkml.kernel.org/r/20160516093428.GA26108@pd.tnic Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-22locking/rwsem, x86: Add frame annotation for ↵Michal Hocko1-0/+2
call_rwsem_down_write_failed_killable() 3387a535ce62 ("x86/asm: Create stack frames in rwsem functions") has added FRAME_{BEGIN,END} annotations to rwsem asm stubs. The patch which has added call_rwsem_down_write_failed_killable() was based on an older tree so it didn't know about annotations. Let's add them. This addresses the following objtool warning: arch/x86/lib/rwsem.o: warning: objtool: call_rwsem_down_write_failed_killable()+0xe: call without frame pointer save/setup Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1460541432-21631-1-git-send-email-mhocko@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13locking/rwsem, x86: Provide __down_write_killable()Michal Hocko1-0/+8
which uses the same fast path as __down_write() except it falls back to call_rwsem_down_write_failed_killable() slow path and return -EINTR if killed. To prevent from code duplication extract the skeleton of __down_write() into a helper macro which just takes the semaphore and the slow path function to be called. Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Chris Zankel <chris@zankel.net> Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Signed-off-by: Jason Low <jason.low2@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/1460041951-22347-11-git-send-email-mhocko@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31x86/cpufeature: Remove cpu_has_xmm2Borislav Petkov1-2/+2
Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-crypto@vger.kernel.org Link: http://lkml.kernel.org/r/1459266123-21878-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-24Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2-4/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - fix hotplug bugs - fix irq live lock - fix various topology handling bugs - fix APIC ACK ordering - fix PV iopl handling - fix speling - fix/tweak memcpy_mcsafe() return value - fix fbcon bug - remove stray prototypes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/msr: Remove unused native_read_tscp() x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck x86/oprofile/nmi: Add missing hotplug FROZEN handling x86/hpet: Use proper mask to modify hotplug action x86/apic/uv: Fix the hotplug notifier x86/apb/timer: Use proper mask to modify hotplug action x86/topology: Use total_cpus not nr_cpu_ids for logical packages x86/topology: Fix Intel HT disable x86/topology: Fix logical package mapping x86/irq: Cure live lock in fixup_irqs() x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known() x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt() x86/iopl: Fix iopl capability check on Xen PV x86/iopl/64: Properly context-switch IOPL on Xen PV selftests/x86: Add an iopl test x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe() x86/video: Don't assume all FB devices are PCI devices arch/x86/irq: Purge useless handler declarations from hw_irq.h x86: Fix misspellings in comments
2016-03-23kernel: add kcov code coverageDmitry Vyukov1-0/+3
kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tavis Ormandy <taviso@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@google.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Drysdale <drysdale@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-21Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds2-4/+13
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'objtool' stack frame validation from Ingo Molnar: "This tree adds a new kernel build-time object file validation feature (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation. It was written by and is maintained by Josh Poimboeuf. The motivation: there's a category of hard to find kernel bugs, most of them in assembly code (but also occasionally in C code), that degrades the quality of kernel stack dumps/backtraces. These bugs are hard to detect at the source code level. Such bugs result in incorrect/incomplete backtraces most of time - but can also in some rare cases result in crashes or other undefined behavior. The build time correctness checking is done via the new 'objtool' user-space utility that was written for this purpose and which is hosted in the kernel repository in tools/objtool/. The tool's (very simple) UI and source code design is shaped after Git and perf and shares quite a bit of infrastructure with tools/perf (which tooling infrastructure sharing effort got merged via perf and is already upstream). Objtool follows the well-known kernel coding style. Objtool does not try to check .c or .S files, it instead analyzes the resulting .o generated machine code from first principles: it decodes the instruction stream and interprets it. (Right now objtool supports the x86-64 architecture.) From tools/objtool/Documentation/stack-validation.txt: "The kernel CONFIG_STACK_VALIDATION option enables a host tool named objtool which runs at compile time. It has a "check" subcommand which analyzes every .o file and ensures the validity of its stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. Currently it only checks frame pointer usage, but there are plans to add CFI validation for C files and CFI generation for asm files. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables." When this new kernel option is enabled (it's disabled by default), the tool, if it finds any suspicious assembly code pattern, outputs warnings in compiler warning format: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup warning: objtool:__schedule()+0x3c0: duplicate frame pointer save warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer ... so that scripts that pick up compiler warnings will notice them. All known warnings triggered by the tool are fixed by the tree, most of the commits in fact prepare the kernel to be warning-free. Most of them are bugfixes or cleanups that stand on their own, but there are also some annotations of 'special' stack frames for justified cases such entries to JIT-ed code (BPF) or really special boot time code. There are two other long-term motivations behind this tool as well: - To improve the quality and reliability of kernel stack frames, so that they can be used for optimized live patching. - To create independent infrastructure to check the correctness of CFI stack frames at build time. CFI debuginfo is notoriously unreliable and we cannot use it in the kernel as-is without extra checking done both on the kernel side and on the build side. The quality of kernel stack frames matters to debuggability as well, so IMO we can merge this without having to consider the live patching or CFI debuginfo angle" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) objtool: Only print one warning per function objtool: Add several performance improvements tools: Copy hashtable.h into tools directory objtool: Fix false positive warnings for functions with multiple switch statements objtool: Rename some variables and functions objtool: Remove superflous INIT_LIST_HEAD objtool: Add helper macros for traversing instructions objtool: Fix false positive warnings related to sibling calls objtool: Compile with debugging symbols objtool: Detect infinite recursion objtool: Prevent infinite recursion in noreturn detection objtool: Detect and warn if libelf is missing and don't break the build tools: Support relative directory path for 'O=' objtool: Support CROSS_COMPILE x86/asm/decoder: Use explicitly signed chars objtool: Enable stack metadata validation on 64-bit x86 objtool: Add CONFIG_STACK_VALIDATION option objtool: Add tool to perform compile-time stack metadata validation x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard sched: Always inline context_switch() ...
2016-03-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-1/+1
Pull networking updates from David Miller: "Highlights: 1) Support more Realtek wireless chips, from Jes Sorenson. 2) New BPF types for per-cpu hash and arrap maps, from Alexei Starovoitov. 3) Make several TCP sysctls per-namespace, from Nikolay Borisov. 4) Allow the use of SO_REUSEPORT in order to do per-thread processing of incoming TCP/UDP connections. The muxing can be done using a BPF program which hashes the incoming packet. From Craig Gallek. 5) Add a multiplexer for TCP streams, to provide a messaged based interface. BPF programs can be used to determine the message boundaries. From Tom Herbert. 6) Add 802.1AE MACSEC support, from Sabrina Dubroca. 7) Avoid factorial complexity when taking down an inetdev interface with lots of configured addresses. We were doing things like traversing the entire address less for each address removed, and flushing the entire netfilter conntrack table for every address as well. 8) Add and use SKB bulk free infrastructure, from Jesper Brouer. 9) Allow offloading u32 classifiers to hardware, and implement for ixgbe, from John Fastabend. 10) Allow configuring IRQ coalescing parameters on a per-queue basis, from Kan Liang. 11) Extend ethtool so that larger link mode masks can be supported. From David Decotigny. 12) Introduce devlink, which can be used to configure port link types (ethernet vs Infiniband, etc.), port splitting, and switch device level attributes as a whole. From Jiri Pirko. 13) Hardware offload support for flower classifiers, from Amir Vadai. 14) Add "Local Checksum Offload". Basically, for a tunneled packet the checksum of the outer header is 'constant' (because with the checksum field filled into the inner protocol header, the payload of the outer frame checksums to 'zero'), and we can take advantage of that in various ways. From Edward Cree" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits) bonding: fix bond_get_stats() net: bcmgenet: fix dma api length mismatch net/mlx4_core: Fix backward compatibility on VFs phy: mdio-thunder: Fix some Kconfig typos lan78xx: add ndo_get_stats64 lan78xx: handle statistics counter rollover RDS: TCP: Remove unused constant RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket net: smc911x: convert pxa dma to dmaengine team: remove duplicate set of flag IFF_MULTICAST bonding: remove duplicate set of flag IFF_MULTICAST net: fix a comment typo ethernet: micrel: fix some error codes ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it bpf, dst: add and use dst_tclassid helper bpf: make skb->tc_classid also readable net: mvneta: bm: clarify dependencies cls_bpf: reset class and reuse major in da ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c ldmvsw: Add ldmvsw.c driver code ...
2016-03-17Merge branch 'x86/cleanups' into x86/urgentIngo Molnar1-1/+1
Pull in some merge window leftovers. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-16x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe()Tony Luck1-3/+4
Returning a 'bool' was very unpopular. Doubly so because the code was just wrong (returning zero for true, one for false; great for shell programming, not so good for C). Change return type to "int". Keep zero as the success indicator because it matches other similar code and people may be more comfortable writing: if (memcpy_mcsafe(to, from, count)) { printk("Sad panda, copy failed\n"); ... } Make the failure return value -EFAULT for now. Reported by: Mika Penttilä <mika.penttila@nextfour.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: mika.penttila@nextfour.com Fixes: 92b0729c34ca ("x86/mm, x86/mce: Add memcpy_mcsafe()") Link: http://lkml.kernel.org/r/695f14233fa7a54fcac4406c706d7fec228e3f4c.1457993040.git.tony.luck@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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