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2018-03-15x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()Peter Zijlstra
commit 531bb52a869a9c6e08c8d17ba955fcbfc18037ad upstream. This is boot code and thus Spectre-safe: we run this _way_ before userspace comes along to have a chance to poison our branch predictor. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/boot, objtool: Annotate indirect jump in secondary_startup_64()Peter Zijlstra
commit bd89004f6305cbf7352238f61da093207ee518d6 upstream. The objtool retpoline validation found this indirect jump. Seeing how it's on CPU bringup before we run userspace it should be safe, annotate it. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/paravirt, objtool: Annotate indirect callsPeter Zijlstra
commit 3010a0663fd949d122eca0561b06b0a9453f7866 upstream. Paravirt emits indirect calls which get flagged by objtool retpoline checks, annotate it away because all these indirect calls will be patched out before we start userspace. This patching happens through alternative_instructions() -> apply_paravirt() -> pv_init_ops.patch() which will eventually end up in paravirt_patch_default(). This function _will_ write direct alternatives. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPPIngo Molnar
commit d72f4e29e6d84b7ec02ae93088aa459ac70e733b upstream. firmware_restrict_branch_speculation_*() recently started using preempt_enable()/disable(), but those are relatively high level primitives and cause build failures on some 32-bit builds. Since we want to keep <asm/nospec-branch.h> low level, convert them to macros to avoid header hell... Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: 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 Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/speculation, objtool: Annotate indirect calls/jumps for objtoolPeter Zijlstra
commit 9e0e3c5130e949c389caabc8033e9799b129e429 upstream. Annotate the indirect calls/jumps in the CALL_NOSPEC/JUMP_NOSPEC alternatives. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/retpoline: Support retpoline builds with ClangDavid Woodhouse
commit 87358710c1fb4f1bf96bbe2349975ff9953fc9b2 upstream. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-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/1519037457-7643-5-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/speculation: Use IBRS if available before calling into firmwareDavid Woodhouse
commit dd84441a797150dcc49298ec95c459a8891d8bb1 upstream. Retpoline means the kernel is safe because it has no indirect branches. But firmware isn't, so use IBRS for firmware calls if it's available. Block preemption while IBRS is set, although in practice the call sites already had to be doing that. Ignore hpwdt.c for now. It's taking spinlocks and calling into firmware code, from an NMI handler. I don't want to touch that with a bargepole. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-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/1519037457-7643-2-git-send-email-dwmw@amazon.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15Revert "x86/retpoline: Simplify vmexit_fill_RSB()"David Woodhouse
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>
2018-03-15x86-64/realmode: Add instruction suffixJan Beulich
commit 8554004a0231dedf44d4d62147fb3d6a6db489aa upstream. Omitting suffixes from instructions in AT&T mode is bad practice when operand size cannot be determined by the assembler from register operands, and is likely going to be warned about by upstream GAS in the future (mine does already). Add the single missing suffix here. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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> Link: http://lkml.kernel.org/r/5A8AF5F602000078001A9230@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/LDT: Avoid warning in 32-bit builds with older gccJan Beulich
commit f2f18b16c779978ece4a04f304a92ff9ac8fbce5 upstream. BUG() doesn't always imply "no return", and hence should be followed by a return statement even if that's obviously (to a human) unreachable. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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> Link: http://lkml.kernel.org/r/5A8AF2AA02000078001A91E9@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/IO-APIC: Avoid warning in 32-bit buildsJan Beulich
commit 6262b6e78ce5ba62be47774ca80f5b0a6f0eb428 upstream. Constants wider than 32 bits should be tagged with ULL. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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> Link: http://lkml.kernel.org/r/5A8AF23F02000078001A91E5@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/asm: Improve how GEN_*_SUFFIXED_RMWcc() specify clobbersJan Beulich
commit 700b7c5409c3e9da279fbea78cf28a78fbc176cd upstream. Commit: df3405245a ("x86/asm: Add suffix macro for GEN_*_RMWcc()") ... introduced "suffix" RMWcc operations, adding bogus clobber specifiers: For one, on x86 there's no point explicitly clobbering "cc". In fact, with GCC properly fixed, this results in an overlap being detected by the compiler between outputs and clobbers. Furthermore it seems bad practice to me to have clobber specification and use of the clobbered register(s) disconnected - it should rather be at the invocation place of that GEN_{UN,BIN}ARY_SUFFIXED_RMWcc() macros that the clobber is specified which this particular invocation needs. Drop the "cc" clobber altogether and move the "cx" one to refcount.h. Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF1F802000078001A91E1@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/mm: Remove stale comment about KMEMCHECKJann Horn
commit 3b3a9268bba62b35a29bafe0931715b1725fdf26 upstream. This comment referred to a conditional call to kmemcheck_hide() that was here until commit 4950276672fc ("kmemcheck: remove annotations"). Now that kmemcheck has been removed, it doesn't make sense anymore. Signed-off-by: Jann Horn <jannh@google.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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> Link: http://lkml.kernel.org/r/20180219175039.253089-1-jannh@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/entry/64: Use 'xorl' for faster register clearingDominik Brodowski
commit ced5d0bf603fa0baee8ea889e1d70971fd210894 upstream. On some x86 CPU microarchitectures using 'xorq' to clear general-purpose registers is slower than 'xorl'. As 'xorl' is sufficient to clear all 64 bits of these registers due to zero-extension [*], switch the x86 64-bit entry code to use 'xorl'. No change in functionality and no change in code size. [*] According to Intel 64 and IA-32 Architecture Software Developer's Manual, section 3.4.1.1, the result of 32-bit operands are "zero- extended to a 64-bit result in the destination general-purpose register." The AMD64 Architecture Programmer’s Manual Volume 3, Appendix B.1, describes the same behaviour. Suggested-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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/20180214175924.23065-3-linux@dominikbrodowski.net [ Improved on the changelog a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/entry: Reduce the code footprint of the 'idtentry' macroDominik Brodowski
commit 9e809d15d6b692fa061d74be7aaab1c79f6784b8 upstream. Play a little trick in the generic PUSH_AND_CLEAR_REGS macro to insert the GP registers "above" the original return address. This allows us to (re-)insert the macro in error_entry() and paranoid_entry() and to remove it from the idtentry macro. This reduces the static footprint significantly: text data bss dec hex filename 24307 0 0 24307 5ef3 entry_64.o-orig 20987 0 0 20987 51fb entry_64.o Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 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/20180214175924.23065-2-linux@dominikbrodowski.net [ Small tweaks to comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/spectre_v2: Don't check microcode versions when running under hypervisorsKonrad Rzeszutek Wilk
commit 36268223c1e9981d6cfc33aff8520b3bde4b8114 upstream. As: 1) It's known that hypervisors lie about the environment anyhow (host mismatch) 2) Even if the hypervisor (Xen, KVM, VMWare, etc) provided a valid "correct" value, it all gets to be very murky when migration happens (do you provide the "new" microcode of the machine?). And in reality the cloud vendors are the ones that should make sure that the microcode that is running is correct and we should just sing lalalala and trust them. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Wanpeng Li <kernellwp@gmail.com> Cc: kvm <kvm@vger.kernel.org> Cc: Krčmář <rkrcmar@redhat.com> Cc: Borislav Petkov <bp@alien8.de> CC: "H. Peter Anvin" <hpa@zytor.com> CC: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180226213019.GE9497@char.us.oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/MCE: Serialize sysfs changesSeunghun Han
commit b3b7c4795ccab5be71f080774c45bbbcc75c2aaf upstream. The check_interval file in /sys/devices/system/machinecheck/machinecheck<cpu number> directory is a global timer value for MCE polling. If it is changed by one CPU, mce_restart() broadcasts the event to other CPUs to delete and restart the MCE polling timer and __mcheck_cpu_init_timer() reinitializes the mce_timer variable. If more than one CPU writes a specific value to the check_interval file concurrently, mce_timer is not protected from such concurrent accesses and all kinds of explosions happen. Since only root can write to those sysfs variables, the issue is not a big deal security-wise. However, concurrent writes to these configuration variables is void of reason so the proper thing to do is to serialize the access with a mutex. Boris: - Make store_int_with_restart() use device_store_ulong() to filter out negative intervals - Limit min interval to 1 second - Correct locking - Massage commit message Signed-off-by: Seunghun Han <kkamagui@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180302202706.9434-1-kkamagui@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15x86/MCE: Save microcode revision in machine check recordsTony Luck
commit fa94d0c6e0f3431523f5701084d799c77c7d4a4f upstream. Updating microcode used to be relatively rare. Now that it has become more common we should save the microcode version in a machine check record to make sure that those people looking at the error have this important information bundled with the rest of the logged information. [ Borislav: Simplify a bit. ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180301233449.24311-1-tony.luck@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11KVM: x86: fix backward migration with async_PFRadim Krčmář
commit fe2a3027e74e40a3ece3a4c1e4e51403090a907a upstream. Guests on new hypersiors might set KVM_ASYNC_PF_DELIVERY_AS_PF_VMEXIT bit when enabling async_PF, but this bit is reserved on old hypervisors, which results in a failure upon migration. To avoid breaking different cases, we are checking for CPUID feature bit before enabling the feature and nothing else. Fixes: 52a5c155cf79 ("KVM: async_pf: Let guest support delivery of async_pf from guest mode") Cc: <stable@vger.kernel.org> Reviewed-by: Wanpeng Li <wanpengli@tencent.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [jwang: port to 4.14] Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11bpf, x64: implement retpoline for tail callDaniel Borkmann
[ upstream commit a493a87f38cfa48caaa95c9347be2d914c6fdf29 ] Implement a retpoline [0] for the BPF tail call JIT'ing that converts the indirect jump via jmp %rax that is used to make the long jump into another JITed BPF image. Since this is subject to speculative execution, we need to control the transient instruction sequence here as well when CONFIG_RETPOLINE is set, and direct it into a pause + lfence loop. The latter aligns also with what gcc / clang emits (e.g. [1]). JIT dump after patch: # bpftool p d x i 1 0: (18) r2 = map[id:1] 2: (b7) r3 = 0 3: (85) call bpf_tail_call#12 4: (b7) r0 = 2 5: (95) exit With CONFIG_RETPOLINE: # bpftool p d j i 1 [...] 33: cmp %edx,0x24(%rsi) 36: jbe 0x0000000000000072 |* 38: mov 0x24(%rbp),%eax 3e: cmp $0x20,%eax 41: ja 0x0000000000000072 | 43: add $0x1,%eax 46: mov %eax,0x24(%rbp) 4c: mov 0x90(%rsi,%rdx,8),%rax 54: test %rax,%rax 57: je 0x0000000000000072 | 59: mov 0x28(%rax),%rax 5d: add $0x25,%rax 61: callq 0x000000000000006d |+ 66: pause | 68: lfence | 6b: jmp 0x0000000000000066 | 6d: mov %rax,(%rsp) | 71: retq | 72: mov $0x2,%eax [...] * relative fall-through jumps in error case + retpoline for indirect jump Without CONFIG_RETPOLINE: # bpftool p d j i 1 [...] 33: cmp %edx,0x24(%rsi) 36: jbe 0x0000000000000063 |* 38: mov 0x24(%rbp),%eax 3e: cmp $0x20,%eax 41: ja 0x0000000000000063 | 43: add $0x1,%eax 46: mov %eax,0x24(%rbp) 4c: mov 0x90(%rsi,%rdx,8),%rax 54: test %rax,%rax 57: je 0x0000000000000063 | 59: mov 0x28(%rax),%rax 5d: add $0x25,%rax 61: jmpq *%rax |- 63: mov $0x2,%eax [...] * relative fall-through jumps in error case - plain indirect jump as before [0] https://support.google.com/faqs/answer/7625886 [1] https://github.com/gcc-mirror/gcc/commit/a31e654fa107be968b802786d747e962c2fcdb2b Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM/x86: remove WARN_ON() for when vm_munmap() failsEric Biggers
commit 103c763c72dd2df3e8c91f2d7ec88f98ed391111 upstream. On x86, special KVM memslots such as the TSS region have anonymous memory mappings created on behalf of userspace, and these mappings are removed when the VM is destroyed. It is however possible for removing these mappings via vm_munmap() to fail. This can most easily happen if the thread receives SIGKILL while it's waiting to acquire ->mmap_sem. This triggers the 'WARN_ON(r < 0)' in __x86_set_memory_region(). syzkaller was able to hit this, using 'exit()' to send the SIGKILL. Note that while the vm_munmap() failure results in the mapping not being removed immediately, it is not leaked forever but rather will be freed when the process exits. It's not really possible to handle this failure properly, so almost every other caller of vm_munmap() doesn't check the return value. It's a limitation of having the kernel manage these mappings rather than userspace. So just remove the WARN_ON() so that users can't spam the kernel log with this warning. Fixes: f0d648bdf0a5 ("KVM: x86: map/unmap private slots in __x86_set_memory_region") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM: x86: fix vcpu initialization with userspace lapicRadim Krčmář
commit b7e31be385584afe7f073130e8e570d53c95f7fe upstream. Moving the code around broke this rare configuration. Use this opportunity to finally call lapic reset from vcpu reset. Reported-by: syzbot+fb7a33a4b6c35007a72b@syzkaller.appspotmail.com Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Fixes: 0b2e9904c159 ("KVM: x86: move LAPIC initialization after VMCS creation") Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR ↵Paolo Bonzini
path as unlikely() commit 946fbbc13dce68902f64515b610eeb2a6c3d7a64 upstream. vmx_vcpu_run() and svm_vcpu_run() are large functions, and giving branch hints to the compiler can actually make a substantial cycle difference by keeping the fast path contiguous in memory. With this optimization, the retpoline-guest/retpoline-host case is about 50 cycles faster. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180222154318.20361-3-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM: x86: move LAPIC initialization after VMCS creationPaolo Bonzini
commit 0b2e9904c15963e715d33e5f3f1387f17d19333a upstream. The initial reset of the local APIC is performed before the VMCS has been created, but it tries to do a vmwrite: vmwrite error: reg 810 value 4a00 (err 18944) CPU: 54 PID: 38652 Comm: qemu-kvm Tainted: G W I 4.16.0-0.rc2.git0.1.fc28.x86_64 #1 Hardware name: Intel Corporation S2600CW/S2600CW, BIOS SE5C610.86B.01.01.0003.090520141303 09/05/2014 Call Trace: vmx_set_rvi [kvm_intel] vmx_hwapic_irr_update [kvm_intel] kvm_lapic_reset [kvm] kvm_create_lapic [kvm] kvm_arch_vcpu_init [kvm] kvm_vcpu_init [kvm] vmx_create_vcpu [kvm_intel] kvm_vm_ioctl [kvm] Move it later, after the VMCS has been created. Fixes: 4191db26b714 ("KVM: x86: Update APICv on APIC reset") Cc: stable@vger.kernel.org Cc: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM/x86: Remove indirect MSR op calls from SPEC_CTRLPaolo Bonzini
commit ecb586bd29c99fb4de599dec388658e74388daad upstream. Having a paravirt indirect call in the IBRS restore path is not a good idea, since we are trying to protect from speculative execution of bogus indirect branch targets. It is also slower, so use native_wrmsrl() on the vmentry path too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Fixes: d28b387fb74da95d69d2615732f50cceb38e9a4d Link: http://lkml.kernel.org/r/20180222154318.20361-2-pbonzini@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08KVM: X86: Fix SMRAM accessing even if VM is shutdownWanpeng Li
commit 95e057e25892eaa48cad1e2d637b80d0f1a4fac5 upstream. Reported by syzkaller: WARNING: CPU: 6 PID: 2434 at arch/x86/kvm/vmx.c:6660 handle_ept_misconfig+0x54/0x1e0 [kvm_intel] CPU: 6 PID: 2434 Comm: repro_test Not tainted 4.15.0+ #4 RIP: 0010:handle_ept_misconfig+0x54/0x1e0 [kvm_intel] Call Trace: vmx_handle_exit+0xbd/0xe20 [kvm_intel] kvm_arch_vcpu_ioctl_run+0xdaf/0x1d50 [kvm] kvm_vcpu_ioctl+0x3e9/0x720 [kvm] do_vfs_ioctl+0xa4/0x6a0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x25/0x9c The testcase creates a first thread to issue KVM_SMI ioctl, and then creates a second thread to mmap and operate on the same vCPU. This triggers a race condition when running the testcase with multiple threads. Sometimes one thread exits with a triple fault while another thread mmaps and operates on the same vCPU. Because CS=0x3000/IP=0x8000 is not mapped, accessing the SMI handler results in an EPT misconfig. This patch fixes it by returning RET_PF_EMULATE in kvm_handle_bad_page(), which will go on to cause an emulation failure and an exit with KVM_EXIT_INTERNAL_ERROR. Reported-by: syzbot+c1d9517cab094dae65e446c0c5b4de6c40f4dc58@syzkaller.appspotmail.com Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08x86/mm: Fix {pmd,pud}_{set,clear}_flags()Jan Beulich
commit 842cef9113c2120f74f645111ded1e020193d84c upstream. Just like pte_{set,clear}_flags() their PMD and PUD counterparts should not do any address translation. This was outright wrong under Xen (causing a dead boot with no useful output on "suitable" systems), and produced needlessly more complicated code (even if just slightly) when paravirt was enabled. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/5A8AF1BB02000078001A91C3@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08x86/cpu_entry_area: Sync cpu_entry_area to initial_page_tableThomas Gleixner
commit 945fd17ab6bab8a4d05da6c3170519fbcfe62ddb upstream. The separation of the cpu_entry_area from the fixmap missed the fact that on 32bit non-PAE kernels the cpu_entry_area mapping might not be covered in initial_page_table by the previous synchronizations. This results in suspend/resume failures because 32bit utilizes initial page table for resume. The absence of the cpu_entry_area mapping results in a triple fault, aka. insta reboot. With PAE enabled this works by chance because the PGD entry which covers the fixmap and other parts incindentally provides the cpu_entry_area mapping as well. Synchronize the initial page table after setting up the cpu entry area. Instead of adding yet another copy of the same code, move it to a function and invoke it from the various places. It needs to be investigated if the existing calls in setup_arch() and setup_per_cpu_areas() can be replaced by the later invocation from setup_cpu_entry_areas(), but that's beyond the scope of this fix. Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Reported-by: Woody Suwalski <terraluna977@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Woody Suwalski <terraluna977@gmail.com> Cc: William Grant <william.grant@canonical.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1802282137290.1392@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08x86/platform/intel-mid: Handle Intel Edison reboot correctlySebastian Panceac
commit 028091f82eefd5e84f81cef81a7673016ecbe78b upstream. When the Intel Edison module is powered with 3.3V, the reboot command makes the module stuck. If the module is powered at a greater voltage, like 4.4V (as the Edison Mini Breakout board does), reboot works OK. The official Intel Edison BSP sends the IPCMSG_COLD_RESET message to the SCU by default. The IPCMSG_COLD_BOOT which is used by the upstream kernel is only sent when explicitely selected on the kernel command line. Use IPCMSG_COLD_RESET unconditionally which makes reboot work independent of the power supply voltage. [ tglx: Massaged changelog ] Fixes: bda7b072de99 ("x86/platform/intel-mid: Implement power off sequence") Signed-off-by: Sebastian Panceac <sebastian@resin.io> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1519810849-15131-1-git-send-email-sebastian@resin.io Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08x86/xen: Zero MSR_IA32_SPEC_CTRL before suspendJuergen Gross
commit 71c208dd54ab971036d83ff6d9837bae4976e623 upstream. Older Xen versions (4.5 and before) might have problems migrating pv guests with MSR_IA32_SPEC_CTRL having a non-zero value. So before suspending zero that MSR and restore it after being resumed. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: https://lkml.kernel.org/r/20180226140818.4849-1-jgross@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-05Merge tag 'v4.15.7' into v4.15/standard/baseBruce Ashfield
This is the 4.15.7 stable release
2018-03-05Merge tag 'v4.15.6' into v4.15/standard/baseBruce Ashfield
This is the 4.15.6 stable release
2018-03-05Merge tag 'v4.15.5' into v4.15/standard/baseBruce Ashfield
This is the 4.15.5 stable release
2018-03-05Merge tag 'v4.15.4' into v4.15/standard/baseBruce Ashfield
This is the 4.15.4 stable release
2018-02-28x86/oprofile: Fix bogus GCC-8 warning in nmi_setup()Arnd Bergmann
commit 85c615eb52222bc5fab6c7190d146bc59fac289e upstream. GCC-8 shows a warning for the x86 oprofile code that copies per-CPU data from CPU 0 to all other CPUs, which when building a non-SMP kernel turns into a memcpy() with identical source and destination pointers: arch/x86/oprofile/nmi_int.c: In function 'mux_clone': arch/x86/oprofile/nmi_int.c:285:2: error: 'memcpy' source argument is the same as destination [-Werror=restrict] memcpy(per_cpu(cpu_msrs, cpu).multiplex, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ per_cpu(cpu_msrs, 0).multiplex, ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sizeof(struct op_msr) * model->num_virt_counters); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/oprofile/nmi_int.c: In function 'nmi_setup': arch/x86/oprofile/nmi_int.c:466:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict] arch/x86/oprofile/nmi_int.c:470:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict] I have analyzed a number of such warnings now: some are valid and the GCC warning is welcome. Others turned out to be false-positives, and GCC was changed to not warn about those any more. This is a corner case that is a false-positive but the GCC developers feel it's better to keep warning about it. In this case, it seems best to work around it by telling GCC a little more clearly that this code path is never hit with an IS_ENABLED() configuration check. Cc:stable as we also want old kernels to build cleanly with GCC-8. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Jessica Yu <jeyu@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Sebor <msebor@gcc.gnu.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert Richter <rric@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: oprofile-list@lists.sf.net Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20180220205826.2008875-1-arnd@arndb.de Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84095 Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28x86/apic/vector: Handle vector release on CPU unplug correctlyThomas Gleixner
commit e84cf6aa501c58bf4bf451f1e425192ec090aed2 upstream. When a irq vector is replaced, then the previous vector is normally released when the first interrupt happens on the new vector. If the target CPU of the previous vector is already offline when the new vector is installed, then the previous vector is silently discarded, which leads to accounting issues causing suspend failures and other problems. Adjust the logic so that the previous vector is freed in the underlying matrix allocator to ensure that the accounting stays correct. Fixes: 69cde0004a4b ("x86/vector: Use matrix allocator for vector assignment") Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180222112316.930791749@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25KVM: x86: fix escape of guest dr6 to the hostWanpeng Li
commit efdab992813fb2ed825745625b83c05032e9cda2 upstream. syzkaller reported: WARNING: CPU: 0 PID: 12927 at arch/x86/kernel/traps.c:780 do_debug+0x222/0x250 CPU: 0 PID: 12927 Comm: syz-executor Tainted: G OE 4.15.0-rc2+ #16 RIP: 0010:do_debug+0x222/0x250 Call Trace: <#DB> debug+0x3e/0x70 RIP: 0010:copy_user_enhanced_fast_string+0x10/0x20 </#DB> _copy_from_user+0x5b/0x90 SyS_timer_create+0x33/0x80 entry_SYSCALL_64_fastpath+0x23/0x9a The testcase sets a watchpoint (with perf_event_open) on a buffer that is passed to timer_create() as the struct sigevent argument. In timer_create(), copy_from_user()'s rep movsb triggers the BP. The testcase also sets the debug registers for the guest. However, KVM only restores host debug registers when the host has active watchpoints, which triggers a race condition when running the testcase with multiple threads. The guest's DR6.BS bit can escape to the host before another thread invokes timer_create(), and do_debug() complains. The fix is to respect do_debug()'s dr6 invariant when leaving KVM. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-25crypto: x86/twofish-3way - Fix %rbp usageEric Biggers
commit d8c7fe9f2a486a6e5f0d5229ca43807af5ab22c6 upstream. Using %rbp as a temporary register breaks frame pointer convention and breaks stack traces when unwinding from an interrupt in the crypto code. In twofish-3way, we can't simply replace %rbp with another register because there are none available. Instead, we use the stack to hold the values that %rbp, %r11, and %r12 were holding previously. Each of these values represents the half of the output from the previous Feistel round that is being passed on unchanged to the following round. They are only used once per round, when they are exchanged with %rax, %rbx, and %rcx. As a result, we free up 3 registers (one per block) and can reassign them so that %rbp is not used, and additionally %r14 and %r15 are not used so they do not need to be saved/restored. There may be a small overhead caused by replacing 'xchg REG, REG' with the needed sequence 'mov MEM, REG; mov REG, MEM; mov REG, REG' once per round. But, counterintuitively, when I tested "ctr-twofish-3way" on a Haswell processor, the new version was actually about 2% faster. (Perhaps 'xchg' is not as well optimized as plain moves.) Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/mm, mm/hwpoison: Don't unconditionally unmap kernel 1:1 pagesTony Luck
commit fd0e786d9d09024f67bd71ec094b110237dc3840 upstream. In the following commit: ce0fa3e56ad2 ("x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages") ... we added code to memory_failure() to unmap the page from the kernel 1:1 virtual address space to avoid speculative access to the page logging additional errors. But memory_failure() may not always succeed in taking the page offline, especially if the page belongs to the kernel. This can happen if there are too many corrected errors on a page and either mcelog(8) or drivers/ras/cec.c asks to take a page offline. Since we remove the 1:1 mapping early in memory_failure(), we can end up with the page unmapped, but still in use. On the next access the kernel crashes :-( There are also various debug paths that call memory_failure() to simulate occurrence of an error. Since there is no actual error in memory, we don't need to map out the page for those cases. Revert most of the previous attempt and keep the solution local to arch/x86/kernel/cpu/mcheck/mce.c. Unmap the page only when: 1) there is a real error 2) memory_failure() succeeds. All of this only applies to 64-bit systems. 32-bit kernel doesn't map all of memory into kernel space. It isn't worth adding the code to unmap the piece that is mapped because nobody would run a 32-bit kernel on a machine that has recoverable machine checks. 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@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Robert (Persistent Memory) <elliott@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: stable@vger.kernel.org #v4.14 Fixes: ce0fa3e56ad2 ("x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages") Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22xen: Fix {set,clear}_foreign_p2m_mapping on autotranslating guestsSimon Gaiser
commit 781198f1f373c3e350dbeb3af04a7d4c81c1b8d7 upstream. Commit 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") removed the check for autotranslation from {set,clear}_foreign_p2m_mapping but those are called by grant-table.c also on PVH/HVM guests. Cc: <stable@vger.kernel.org> # 4.14 Fixes: 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/smpboot: Fix uncore_pci_remove() indexing bug when hot-removing a ↵Masayoshi Mizuma
physical CPU commit 295cc7eb314eb3321fb6d67ca6f7305f5c50d10f upstream. When a physical CPU is hot-removed, the following warning messages are shown while the uncore device is removed in uncore_pci_remove(): WARNING: CPU: 120 PID: 5 at arch/x86/events/intel/uncore.c:988 uncore_pci_remove+0xf1/0x110 ... CPU: 120 PID: 5 Comm: kworker/u1024:0 Not tainted 4.15.0-rc8 #1 Workqueue: kacpi_hotplug acpi_hotplug_work_fn ... Call Trace: pci_device_remove+0x36/0xb0 device_release_driver_internal+0x145/0x210 pci_stop_bus_device+0x76/0xa0 pci_stop_root_bus+0x44/0x60 acpi_pci_root_remove+0x1f/0x80 acpi_bus_trim+0x54/0x90 acpi_bus_trim+0x2e/0x90 acpi_device_hotplug+0x2bc/0x4b0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x141/0x340 worker_thread+0x47/0x3e0 kthread+0xf5/0x130 When uncore_pci_remove() runs, it tries to get the package ID to clear the value of uncore_extra_pci_dev[].dev[] by using topology_phys_to_logical_pkg(). The warning messesages are shown because topology_phys_to_logical_pkg() returns -1. arch/x86/events/intel/uncore.c: static void uncore_pci_remove(struct pci_dev *pdev) { ... phys_id = uncore_pcibus_to_physid(pdev->bus); ... pkg = topology_phys_to_logical_pkg(phys_id); // returns -1 for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) { if (uncore_extra_pci_dev[pkg].dev[i] == pdev) { uncore_extra_pci_dev[pkg].dev[i] = NULL; break; } } WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX); // <=========== HERE!! topology_phys_to_logical_pkg() tries to find cpuinfo_x86->phys_proc_id that matches the phys_pkg argument. arch/x86/kernel/smpboot.c: int topology_phys_to_logical_pkg(unsigned int phys_pkg) { int cpu; for_each_possible_cpu(cpu) { struct cpuinfo_x86 *c = &cpu_data(cpu); if (c->initialized && c->phys_proc_id == phys_pkg) return c->logical_proc_id; } return -1; } However, the phys_proc_id was already set to 0 by remove_siblinginfo() when the CPU was offlined. So, topology_phys_to_logical_pkg() cannot find the correct logical_proc_id and always returns -1. As the result, uncore_pci_remove() calls WARN_ON_ONCE() and the warning messages are shown. What is worse is that the bogus 'pkg' index results in two bugs: - We dereference uncore_extra_pci_dev[] with a negative index - We fail to clean up a stale pointer in uncore_extra_pci_dev[][] To fix these bugs, remove the clearing of ->phys_proc_id from remove_siblinginfo(). This should not cause any problems, because ->phys_proc_id is not used after it is hot-removed and it is re-set while hot-adding. Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: yasu.isimatu@gmail.com Cc: <stable@vger.kernel.org> Fixes: 30bb9811856f ("x86/topology: Avoid wasting 128k for package id array") Link: http://lkml.kernel.org/r/ed738d54-0f01-b38b-b794-c31dc118c207@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/entry/64: Fix CR3 restore in paranoid_exit()Ingo Molnar
commit e48657573481a5dff7cfdc3d57005c80aa816500 upstream. Josh Poimboeuf noticed the following bug: "The paranoid exit code only restores the saved CR3 when it switches back to the user GS. However, even in the kernel GS case, it's possible that it needs to restore a user CR3, if for example, the paranoid exception occurred in the syscall exit path between SWITCH_TO_USER_CR3_STACK and SWAPGS." Josh also confirmed via targeted testing that it's possible to hit this bug. Fix the bug by also restoring CR3 in the paranoid_exit_no_swapgs branch. The reason we haven't seen this bug reported by users yet is probably because "paranoid" entry points are limited to the following cases: idtentry double_fault do_double_fault has_error_code=1 paranoid=2 idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK idtentry int3 do_int3 has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK idtentry machine_check do_mce has_error_code=0 paranoid=1 Amongst those entry points only machine_check is one that will interrupt an IRQS-off critical section asynchronously - and machine check events are rare. The other main asynchronous entries are NMI entries, which can be very high-freq with perf profiling, but they are special: they don't use the 'idtentry' macro but are open coded and restore user CR3 unconditionally so don't have this bug. Reported-and-tested-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180214073910.boevmg65upbk3vqb@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/cpu: Change type of x86_cache_size variable to unsigned intGustavo A. R. Silva
commit 24dbc6000f4b9b0ef5a9daecb161f1907733765a upstream. Currently, x86_cache_size is of type int, which makes no sense as we will never have a valid cache size equal or less than 0. So instead of initializing this variable to -1, it can perfectly be initialized to 0 and use it as an unsigned variable instead. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Addresses-Coverity-ID: 1464429 Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/spectre: Fix an error messageDan Carpenter
commit 9de29eac8d2189424d81c0d840cd0469aa3d41c8 upstream. If i == ARRAY_SIZE(mitigation_options) then we accidentally print garbage from one space beyond the end of the mitigation_options[] array. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-janitors@vger.kernel.org Fixes: 9005c6834c0f ("x86/spectre: Simplify spectre_v2 command line parsing") Link: http://lkml.kernel.org/r/20180214071416.GA26677@mwanda 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 Zhang
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>
2018-02-22x86/mm: Rename flush_tlb_single() and flush_tlb_one() to ↵Andy Lutomirski
__flush_tlb_one_[user|kernel]() commit 1299ef1d8870d2d9f09a5aadf2f8b2c887c2d033 upstream. flush_tlb_single() and flush_tlb_one() sound almost identical, but they really mean "flush one user translation" and "flush one kernel translation". Rename them to flush_tlb_one_user() and flush_tlb_one_kernel() to make the semantics more obvious. [ I was looking at some PTI-related code, and the flush-one-address code is unnecessarily hard to understand because the names of the helpers are uninformative. This came up during PTI review, but no one got around to doing it. ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Hugh Dickins <hughd@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux-MM <linux-mm@kvack.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/3303b02e3c3d049dc5235d5651e0ae6d29a34354.1517414378.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/speculation: Add <asm/msr-index.h> dependencyPeter Zijlstra
commit ea00f301285ea2f07393678cd2b6057878320c9d upstream. Joe Konno reported a compile failure resulting from using an MSR without inclusion of <asm/msr-index.h>, and while the current code builds fine (by accident) this needs fixing for future patches. Reported-by: Joe Konno <joe.konno@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arjan@linux.intel.com Cc: bp@alien8.de Cc: dan.j.williams@intel.com Cc: dave.hansen@linux.intel.com Cc: dwmw2@infradead.org Cc: dwmw@amazon.co.uk Cc: gregkh@linuxfoundation.org Cc: hpa@zytor.com Cc: jpoimboe@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: luto@kernel.org Fixes: 20ffa1caecca ("x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support") Link: http://lkml.kernel.org/r/20180213132819.GJ25201@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/speculation: Fix up array_index_nospec_mask() asm constraintDan Williams
commit be3233fbfcb8f5acb6e3bcd0895c3ef9e100d470 upstream. Allow the compiler to handle @size as an immediate value or memory directly rather than allocating a register. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/151797010204.1289.1510000292250184993.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/debug: Use UD2 for WARN()Peter Zijlstra
commit 3b3a371cc9bc980429baabe0a8e5f307f3d1f463 upstream. Since the Intel SDM added an ModR/M byte to UD0 and binutils followed that specification, we now cannot disassemble our kernel anymore. This now means Intel and AMD disagree on the encoding of UD0. And instead of playing games with additional bytes that are valid ModR/M and single byte instructions (0xd6 for instance), simply use UD2 for both WARN() and BUG(). Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> 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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180208194406.GD25181@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22x86/debug, objtool: Annotate WARN()-related UD2 as reachableJosh Poimboeuf
commit 2b5db66862b95532cb6cca8165ae6eb73633cf85 upstream. By default, objtool assumes that a UD2 is a dead end. This is mainly because GCC 7+ sometimes inserts a UD2 when it detects a divide-by-zero condition. Now that WARN() is moving back to UD2, annotate the code after it as reachable so objtool can follow the code flow. Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> 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> Cc: kbuild test robot <fengguang.wu@intel.com> Link: http://lkml.kernel.org/r/0e483379275a42626ba8898117f918e1bf661e40.1518130694.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>