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2018-09-02Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds20-46/+167
Pull x86 fixes from Thomas Gleixner: "Speculation: - Make the microcode check more robust - Make the L1TF memory limit depend on the internal cache physical address space and not on the CPUID advertised physical address space, which might be significantly smaller. This avoids disabling L1TF on machines which utilize the full physical address space. - Fix the GDT mapping for EFI calls on 32bit PTI - Fix the MCE nospec implementation to prevent #GP Fixes and robustness: - Use the proper operand order for LSL in the VDSO - Prevent NMI uaccess race against CR3 switching - Add a lockdep check to verify that text_mutex is held in text_poke() functions - Repair the fallout of giving native_restore_fl() a prototype - Prevent kernel memory dumps based on usermode RIP - Wipe KASAN shadow stack before rewinding the stack to prevent false positives - Move the AMS GOTO enforcement to the actual build stage to allow user API header extraction without a compiler - Fix a section mismatch introduced by the on demand VDSO mapping change Miscellaneous: - Trivial typo, GCC quirk removal and CC_SET/OUT() cleanups" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pti: Fix section mismatch warning/error x86/vdso: Fix lsl operand order x86/mce: Fix set_mce_nospec() to avoid #GP fault x86/efi: Load fixmap GDT in efi_call_phys_epilog() x86/nmi: Fix NMI uaccess race against CR3 switching x86: Allow generating user-space headers without a compiler x86/dumpstack: Don't dump kernel memory based on usermode RIP x86/asm: Use CC_SET()/CC_OUT() in __gen_sigismember() x86/alternatives: Lockdep-enforce text_mutex in text_poke*() x86/entry/64: Wipe KASAN stack shadow before rewind_stack_do_exit() x86/irqflags: Mark native_restore_fl extern inline x86/build: Remove jump label quirk for GCC older than 4.5.2 x86/Kconfig: Fix trivial typo x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+ x86/spectre: Add missing family 6 check to microcode check
2018-09-02x86/pti: Fix section mismatch warning/errorRandy Dunlap1-1/+1
Fix the section mismatch warning in arch/x86/mm/pti.c: WARNING: vmlinux.o(.text+0x6972a): Section mismatch in reference from the function pti_clone_pgtable() to the function .init.text:pti_user_pagetable_walk_pte() The function pti_clone_pgtable() references the function __init pti_user_pagetable_walk_pte(). This is often because pti_clone_pgtable lacks a __init annotation or the annotation of pti_user_pagetable_walk_pte is wrong. FATAL: modpost: Section mismatches detected. Fixes: 85900ea51577 ("x86/pti: Map the vsyscall page if needed") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/43a6d6a3-d69d-5eda-da09-0b1c88215a2a@infradead.org
2018-09-01x86/vdso: Fix lsl operand orderSamuel Neves1-1/+1
In the __getcpu function, lsl is using the wrong target and destination registers. Luckily, the compiler tends to choose %eax for both variables, so it has been working so far. Fixes: a582c540ac1b ("x86/vdso: Use RDPID in preference to LSL when available") Signed-off-by: Samuel Neves <sneves@dei.uc.pt> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180901201452.27828-1-sneves@dei.uc.pt
2018-09-01x86/mce: Fix set_mce_nospec() to avoid #GP faultLuckTony1-1/+24
The trick with flipping bit 63 to avoid loading the address of the 1:1 mapping of the poisoned page while the 1:1 map is updated used to work when unmapping the page. But it falls down horribly when attempting to directly set the page as uncacheable. The problem is that when the cache mode is changed to uncachable, the pages needs to be flushed from the cache first. But the decoy address is non-canonical due to bit 63 flipped, and the CLFLUSH instruction throws a #GP fault. Add code to change_page_attr_set_clr() to fix the address before calling flush. Fixes: 284ce4011ba6 ("x86/memory_failure: Introduce {set, clear}_mce_nospec()") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Anvin <hpa@zytor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Link: https://lkml.kernel.org/r/20180831165506.GA9605@agluck-desk
2018-08-31x86/efi: Load fixmap GDT in efi_call_phys_epilog()Joerg Roedel1-6/+2
When PTI is enabled on x86-32 the kernel uses the GDT mapped in the fixmap for the simple reason that this address is also mapped for user-space. The efi_call_phys_prolog()/efi_call_phys_epilog() wrappers change the GDT to call EFI runtime services and switch back to the kernel GDT when they return. But the switch-back uses the writable GDT, not the fixmap GDT. When that happened and and the CPU returns to user-space it switches to the user %cr3 and tries to restore user segment registers. This fails because the writable GDT is not mapped in the user page-table, and without a GDT the fault handlers also can't be launched. The result is a triple fault and reboot of the machine. Fix that by restoring the GDT back to the fixmap GDT which is also mapped in the user page-table. Fixes: 7757d607c6b3 x86/pti: ('Allow CONFIG_PAGE_TABLE_ISOLATION for x86_32') Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: hpa@zytor.com Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/1535702738-10971-1-git-send-email-joro@8bytes.org
2018-08-31Merge tag 'for-linus-4.19b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds2-10/+6
Pull xen fixes from Juergen Gross: - minor cleanup avoiding a warning when building with new gcc - a patch to add a new sysfs node for Xen frontend/backend drivers to make it easier to obtain the state of a pv device - two fixes for 32-bit pv-guests to avoid intermediate L1TF vulnerable PTEs * tag 'for-linus-4.19b-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: remove redundant variable save_pud xen: export device state to sysfs x86/pae: use 64 bit atomic xchg function in native_ptep_get_and_clear x86/xen: don't write ptes directly in 32-bit PV guests
2018-08-31x86/nmi: Fix NMI uaccess race against CR3 switchingAndy Lutomirski4-1/+53
A NMI can hit in the middle of context switching or in the middle of switch_mm_irqs_off(). In either case, CR3 might not match current->mm, which could cause copy_from_user_nmi() and friends to read the wrong memory. Fix it by adding a new nmi_uaccess_okay() helper and checking it in copy_from_user_nmi() and in __copy_from_user_nmi()'s callers. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rik van Riel <riel@surriel.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jann Horn <jannh@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/dd956eba16646fd0b15c3c0741269dfd84452dac.1535557289.git.luto@kernel.org
2018-08-31x86: Allow generating user-space headers without a compilerBen Hutchings1-4/+7
When bootstrapping an architecture, it's usual to generate the kernel's user-space headers (make headers_install) before building a compiler. Move the compiler check (for asm goto support) to the archprepare target so that it is only done when building code for the target. Fixes: e501ce957a78 ("x86: Force asm-goto") Reported-by: Helmut Grohne <helmutg@debian.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180829194317.GA4765@decadent.org.uk
2018-08-31x86/dumpstack: Don't dump kernel memory based on usermode RIPJann Horn3-5/+15
show_opcodes() is used both for dumping kernel instructions and for dumping user instructions. If userspace causes #PF by jumping to a kernel address, show_opcodes() can be reached with regs->ip controlled by the user, pointing to kernel code. Make sure that userspace can't trick us into dumping kernel memory into dmesg. Fixes: 7cccf0725cf7 ("x86/dumpstack: Add a show_ip() function") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: security@kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180828154901.112726-1-jannh@google.com
2018-08-30x86/asm: Use CC_SET()/CC_OUT() in __gen_sigismember()Uros Bizjak1-3/+4
Replace open-coded set instructions with CC_SET()/CC_OUT(). Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180814165951.13538-1-ubizjak@gmail.com
2018-08-30x86/alternatives: Lockdep-enforce text_mutex in text_poke*()Jiri Kosina1-4/+5
text_poke() and text_poke_bp() must be called with text_mutex held. Put proper lockdep anotation in place instead of just mentioning the requirement in a comment. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1808280853520.25787@cbobk.fhfr.pm
2018-08-30x86/entry/64: Wipe KASAN stack shadow before rewind_stack_do_exit()Jann Horn1-0/+4
Reset the KASAN shadow state of the task stack before rewinding RSP. Without this, a kernel oops will leave parts of the stack poisoned, and code running under do_exit() can trip over such poisoned regions and cause nonsensical false-positive KASAN reports about stack-out-of-bounds bugs. This does not wipe the exception stacks; if an oops happens on an exception stack, it might result in random KASAN false-positives from other tasks afterwards. This is probably relatively uninteresting, since if the kernel oopses on an exception stack, there are most likely bigger things to worry about. It'd be more interesting if vmapped stacks and KASAN were compatible, since then handle_stack_overflow() would oops from exception stack context. Fixes: 2deb4be28077 ("x86/dumpstack: When OOPSing, rewind the stack before do_exit()") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: kasan-dev@googlegroups.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180828184033.93712-1-jannh@google.com
2018-08-30x86/irqflags: Mark native_restore_fl extern inlineNick Desaulniers1-1/+2
This should have been marked extern inline in order to pick up the out of line definition in arch/x86/kernel/irqflags.S. Fixes: 208cbb325589 ("x86/irqflags: Provide a declaration for native_save_fl") Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180827214011.55428-1-ndesaulniers@google.com
2018-08-30x86/build: Remove jump label quirk for GCC older than 4.5.2Masahiro Yamada1-12/+0
Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6") bumped the minimum GCC version to 4.6 for all architectures. Remove the workaround code. It was the only user of cc-if-fullversion. Remove the macro as well. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Michal Marek <michal.lkml@markovi.net> Cc: linux-kbuild@vger.kernel.org Link: https://lkml.kernel.org/r/1535348714-25457-1-git-send-email-yamada.masahiro@socionext.com
2018-08-29Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds1-33/+33
Pull crypto fixes from Herbert Xu: - Check for the right CPU feature bit in sm4-ce on arm64. - Fix scatterwalk WARN_ON in aes-gcm-ce on arm64. - Fix unaligned fault in aesni on x86. - Fix potential NULL pointer dereference on exit in chtls. - Fix DMA mapping direction for RSA in caam. - Fix error path return value for xts setkey in caam. - Fix address endianness when DMA unmapping in caam. - Fix sleep-in-atomic in vmx. - Fix command corruption when queue is full in cavium/nitrox. * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: cavium/nitrox - fix for command corruption in queue full case with backlog submissions. crypto: vmx - Fix sleep-in-atomic bugs crypto: arm64/aes-gcm-ce - fix scatterwalk API violation crypto: aesni - Use unaligned loads from gcm_context_data crypto: chtls - fix null dereference chtls_free_uld() crypto: arm64/sm4-ce - check for the right CPU feature bit crypto: caam - fix DMA mapping direction for RSA forms 2 & 3 crypto: caam/qi - fix error path in xts setkey crypto: caam/jr - fix descriptor DMA unmapping
2018-08-28x86/xen: remove redundant variable save_pudColin Ian King1-2/+0
Variable save_pud is being assigned but is never used hence it is redundant and can be removed. Cleans up clang warning: variable 'save_pud' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-08-27x86/pae: use 64 bit atomic xchg function in native_ptep_get_and_clearJuergen Gross1-4/+3
Using only 32-bit writes for the pte will result in an intermediate L1TF vulnerable PTE. When running as a Xen PV guest this will at once switch the guest to shadow mode resulting in a loss of performance. Use arch_atomic64_xchg() instead which will perform the requested operation atomically with all 64 bits. Some performance considerations according to: https://software.intel.com/sites/default/files/managed/ad/dc/Intel-Xeon-Scalable-Processor-throughput-latency.pdf The main number should be the latency, as there is no tight loop around native_ptep_get_and_clear(). "lock cmpxchg8b" has a latency of 20 cycles, while "lock xchg" (with a memory operand) isn't mentioned in that document. "lock xadd" (with xadd having 3 cycles less latency than xchg) has a latency of 11, so we can assume a latency of 14 for "lock xchg". Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Beulich <jbeulich@suse.com> Tested-by: Jason Andryuk <jandryuk@gmail.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-08-27x86/xen: don't write ptes directly in 32-bit PV guestsJuergen Gross1-4/+3
In some cases 32-bit PAE PV guests still write PTEs directly instead of using hypercalls. This is especially bad when clearing a PTE as this is done via 32-bit writes which will produce intermediate L1TF attackable PTEs. Change the code to use hypercalls instead. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-08-27x86/Kconfig: Fix trivial typoNikolas Nyby1-1/+1
Fix a typo in the Kconfig help text: adverticed -> advertised. Signed-off-by: Nikolas Nyby <nikolas@gnu.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: trivial@kernel.org Cc: tglx@linutronix.de Cc: x86@kernel.org Link: https://lkml.kernel.org/r/20180825231054.23813-1-nikolas@gnu.org
2018-08-27x86/speculation/l1tf: Increase l1tf memory limit for Nehalem+Andi Kleen3-6/+45
On Nehalem and newer core CPUs the CPU cache internally uses 44 bits physical address space. The L1TF workaround is limited by this internal cache address width, and needs to have one bit free there for the mitigation to work. Older client systems report only 36bit physical address space so the range check decides that L1TF is not mitigated for a 36bit phys/32GB system with some memory holes. But since these actually have the larger internal cache width this warning is bogus because it would only really be needed if the system had more than 43bits of memory. Add a new internal x86_cache_bits field. Normally it is the same as the physical bits field reported by CPUID, but for Nehalem and newerforce it to be at least 44bits. Change the L1TF memory size warning to use the new cache_bits field to avoid bogus warnings and remove the bogus comment about memory size. Fixes: 17dbca119312 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Reported-by: George Anchev <studio@anchev.net> Reported-by: Christopher Snowhill <kode54@gmail.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: Michael Hocko <mhocko@suse.com> Cc: vbabka@suse.cz Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180824170351.34874-1-andi@firstfloor.org
2018-08-27x86/spectre: Add missing family 6 check to microcode checkAndi Kleen1-0/+3
The check for Spectre microcodes does not check for family 6, only the model numbers. Add a family 6 check to avoid ambiguity with other families. Fixes: a5b296636453 ("x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes") Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180824170351.34874-2-andi@firstfloor.org
2018-08-26Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+33
Pull perf updates from Thomas Gleixner: "Kernel: - Improve kallsyms coverage - Add x86 entry trampolines to kcore - Fix ARM SPE handling - Correct PPC event post processing Tools: - Make the build system more robust - Small fixes and enhancements all over the place - Update kernel ABI header copies - Preparatory work for converting libtraceevnt to a shared library - License cleanups" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits) tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy' tools arch x86: Update tools's copy of cpufeatures.h perf python: Fix pyrf_evlist__read_on_cpu() interface perf mmap: Store real cpu number in 'struct perf_mmap' perf tools: Remove ext from struct kmod_path perf tools: Add gzip_is_compressed function perf tools: Add lzma_is_compressed function perf tools: Add is_compressed callback to compressions array perf tools: Move the temp file processing into decompress_kmodule perf tools: Use compression id in decompress_kmodule() perf tools: Store compression id into struct dso perf tools: Add compression id into 'struct kmod_path' perf tools: Make is_supported_compression() static perf tools: Make decompress_to_file() function static perf tools: Get rid of dso__needs_decompress() call in __open_dso() perf tools: Get rid of dso__needs_decompress() call in symbol__disassemble() perf tools: Get rid of dso__needs_decompress() call in read_object_code() tools lib traceevent: Change to SPDX License format perf llvm: Allow passing options to llc in addition to clang perf parser: Improve error message for PMU address filters ...
2018-08-26Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds8-10/+15
Pull x86 fixes from Thomas Gleixner: - Correct the L1TF fallout on 32bit and the off by one in the 'too much RAM for protection' calculation. - Add a helpful kernel message for the 'too much RAM' case - Unbreak the VDSO in case that the compiler desides to use indirect jumps/calls and emits retpolines which cannot be resolved because the kernel uses its own thunks, which does not work for the VDSO. Make it use the builtin thunks. - Re-export start_thread() which was unexported when the 32/64bit implementation was unified. start_thread() is required by modular binfmt handlers. - Trivial cleanups * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/speculation/l1tf: Suggest what to do on systems with too much RAM x86/speculation/l1tf: Fix off-by-one error when warning that system has too much RAM x86/kvm/vmx: Remove duplicate l1d flush definitions x86/speculation/l1tf: Fix overflow in l1tf_pfn_limit() on 32bit x86/process: Re-export start_thread() x86/mce: Add notifier_block forward declaration x86/vdso: Fix vDSO build if a retpoline is emitted
2018-08-25Merge tag 'libnvdimm-for-4.19_dax-memory-failure' of gitolite.kernel.org:pub/scm/linux/kernel/git/nvdimm/nvdimmLinus Torvalds4-50/+61
Pull libnvdimm memory-failure update from Dave Jiang: "As it stands, memory_failure() gets thoroughly confused by dev_pagemap backed mappings. The recovery code has specific enabling for several possible page states and needs new enabling to handle poison in dax mappings. In order to support reliable reverse mapping of user space addresses: 1/ Add new locking in the memory_failure() rmap path to prevent races that would typically be handled by the page lock. 2/ Since dev_pagemap pages are hidden from the page allocator and the "compound page" accounting machinery, add a mechanism to determine the size of the mapping that encompasses a given poisoned pfn. 3/ Given pmem errors can be repaired, change the speculatively accessed poison protection, mce_unmap_kpfn(), to be reversible and otherwise allow ongoing access from the kernel. A side effect of this enabling is that MADV_HWPOISON becomes usable for dax mappings, however the primary motivation is to allow the system to survive userspace consumption of hardware-poison via dax. Specifically the current behavior is: mce: Uncorrected hardware memory error in user-access at af34214200 {1}[Hardware Error]: It has been corrected by h/w and requires no further action mce: [Hardware Error]: Machine check events logged {1}[Hardware Error]: event severity: corrected Memory failure: 0xaf34214: reserved kernel page still referenced by 1 users [..] Memory failure: 0xaf34214: recovery action for reserved kernel page: Failed mce: Memory error not recovered <reboot> ...and with these changes: Injecting memory failure for pfn 0x20cb00 at process virtual address 0x7f763dd00000 Memory failure: 0x20cb00: Killing dax-pmd:5421 due to hardware memory corruption Memory failure: 0x20cb00: recovery action for dax page: Recovered Given all the cross dependencies I propose taking this through nvdimm.git with acks from Naoya, x86/core, x86/RAS, and of course dax folks" * tag 'libnvdimm-for-4.19_dax-memory-failure' of gitolite.kernel.org:pub/scm/linux/kernel/git/nvdimm/nvdimm: libnvdimm, pmem: Restore page attributes when clearing errors x86/memory_failure: Introduce {set, clear}_mce_nospec() x86/mm/pat: Prepare {reserve, free}_memtype() for "decoy" addresses mm, memory_failure: Teach memory_failure() about dev_pagemap pages filesystem-dax: Introduce dax_lock_mapping_entry() mm, memory_failure: Collect mapping size in collect_procs() mm, madvise_inject_error: Let memory_failure() optionally take a page reference mm, dev_pagemap: Do not clear ->mapping on final put mm, madvise_inject_error: Disable MADV_SOFT_OFFLINE for ZONE_DEVICE pages filesystem-dax: Set page->index device-dax: Set page->index device-dax: Enable page_mapping() device-dax: Convert to vmf_insert_mixed and vm_fault_t
2018-08-25Merge tag 'kbuild-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuildLinus Torvalds3-7/+7
Pull more Kbuild updates from Masahiro Yamada: - add build_{menu,n,g,x}config targets for compile-testing Kconfig - fix and improve recursive dependency detection in Kconfig - fix parallel building of menuconfig/nconfig - fix syntax error in clang-version.sh - suppress distracting log from syncconfig - remove obsolete "rpm" target - remove VMLINUX_SYMBOL(_STR) macro entirely - fix microblaze build with CONFIG_DYNAMIC_FTRACE - move compiler test for dead code/data elimination to Kconfig - rename well-known LDFLAGS variable to KBUILD_LDFLAGS - misc fixes and cleanups * tag 'kbuild-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: rename LDFLAGS to KBUILD_LDFLAGS kbuild: pass LDFLAGS to recordmcount.pl kbuild: test dead code/data elimination support in Kconfig initramfs: move gen_initramfs_list.sh from scripts/ to usr/ vmlinux.lds.h: remove stale <linux/export.h> include export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() Coccinelle: remove pci_alloc_consistent semantic to detect in zalloc-simple.cocci kbuild: make sorting initramfs contents independent of locale kbuild: remove "rpm" target, which is alias of "rpm-pkg" kbuild: Fix LOADLIBES rename in Documentation/kbuild/makefiles.txt kconfig: suppress "configuration written to .config" for syncconfig kconfig: fix "Can't open ..." in parallel build kbuild: Add a space after `!` to prevent parsing as file pattern scripts: modpost: check memory allocation results kconfig: improve the recursive dependency report kconfig: report recursive dependency involving 'imply' kconfig: error out when seeing recursive dependency kconfig: add build-only configurator targets scripts/dtc: consolidate include path options in Makefile
2018-08-25crypto: aesni - Use unaligned loads from gcm_context_dataDave Watson1-33/+33
A regression was reported bisecting to 1476db2d12 "Move HashKey computation from stack to gcm_context". That diff moved HashKey computation from the stack, which was explicitly aligned in the asm, to a struct provided from the C code, depending on AESNI_ALIGN_ATTR for alignment. It appears some compilers may not align this struct correctly, resulting in a crash on the movdqa instruction when attempting to encrypt or decrypt data. Fix by using unaligned loads for the HashKeys. On modern hardware there is no perf difference between the unaligned and aligned loads. All other accesses to gcm_context_data already use unaligned loads. Reported-by: Mauro Rossi <issor.oruam@gmail.com> Fixes: 1476db2d12 ("Move HashKey computation from stack to gcm_context") Cc: <stable@vger.kernel.org> Signed-off-by: Dave Watson <davejwatson@fb.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-24Merge tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds2-0/+13
Pull IOMMU updates from Joerg Roedel: - PASID table handling updates for the Intel VT-d driver. It implements a global PASID space now so that applications usings multiple devices will just have one PASID. - A new config option to make iommu passthroug mode the default. - New sysfs attribute for iommu groups to export the type of the default domain. - A debugfs interface (for debug only) usable by IOMMU drivers to export internals to user-space. - R-Car Gen3 SoCs support for the ipmmu-vmsa driver - The ARM-SMMU now aborts transactions from unknown devices and devices not attached to any domain. - Various cleanups and smaller fixes all over the place. * tag 'iommu-updates-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (42 commits) iommu/omap: Fix cache flushes on L2 table entries iommu: Remove the ->map_sg indirection iommu/arm-smmu-v3: Abort all transactions if SMMU is enabled in kdump kernel iommu/arm-smmu-v3: Prevent any devices access to memory without registration iommu/ipmmu-vmsa: Don't register as BUS IOMMU if machine doesn't have IPMMU-VMSA iommu/ipmmu-vmsa: Clarify supported platforms iommu/ipmmu-vmsa: Fix allocation in atomic context iommu: Add config option to set passthrough as default iommu: Add sysfs attribyte for domain type iommu/arm-smmu-v3: sync the OVACKFLG to PRIQ consumer register iommu/arm-smmu: Error out only if not enough context interrupts iommu/io-pgtable-arm-v7s: Abort allocation when table address overflows the PTE iommu/io-pgtable-arm: Fix pgtable allocation in selftest iommu/vt-d: Remove the obsolete per iommu pasid tables iommu/vt-d: Apply per pci device pasid table in SVA iommu/vt-d: Allocate and free pasid table iommu/vt-d: Per PCI device pasid table interfaces iommu/vt-d: Add for_each_device_domain() helper iommu/vt-d: Move device_domain_info to header iommu/vt-d: Apply global PASID in SVA ...
2018-08-24x86/speculation/l1tf: Suggest what to do on systems with too much RAMVlastimil Babka1-0/+4
Two users have reported [1] that they have an "extremely unlikely" system with more than MAX_PA/2 memory and L1TF mitigation is not effective. Make the warning more helpful by suggesting the proper mem=X kernel boot parameter to make it effective and a link to the L1TF document to help decide if the mitigation is worth the unusable RAM. [1] https://bugzilla.suse.com/show_bug.cgi?id=1105536 Suggested-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/966571f0-9d7f-43dc-92c6-a10eec7a1254@suse.cz
2018-08-24x86/speculation/l1tf: Fix off-by-one error when warning that system has too much RAMVlastimil Babka3-3/+3
Two users have reported [1] that they have an "extremely unlikely" system with more than MAX_PA/2 memory and L1TF mitigation is not effective. In fact it's a CPU with 36bits phys limit (64GB) and 32GB memory, but due to holes in the e820 map, the main region is almost 500MB over the 32GB limit: [ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000081effffff] usable Suggestions to use 'mem=32G' to enable the L1TF mitigation while losing the 500MB revealed, that there's an off-by-one error in the check in l1tf_select_mitigation(). l1tf_pfn_limit() returns the last usable pfn (inclusive) and the range check in the mitigation path does not take this into account. Instead of amending the range check, make l1tf_pfn_limit() return the first PFN which is over the limit which is less error prone. Adjust the other users accordingly. [1] https://bugzilla.suse.com/show_bug.cgi?id=1105536 Fixes: 17dbca119312 ("x86/speculation/l1tf: Add sysfs reporting for l1tf") Reported-by: George Anchev <studio@anchev.net> Reported-by: Christopher Snowhill <kode54@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180823134418.17008-1-vbabka@suse.cz
2018-08-24kbuild: rename LDFLAGS to KBUILD_LDFLAGSMasahiro Yamada3-7/+7
Commit a0f97e06a43c ("kbuild: enable 'make CFLAGS=...' to add additional options to CC") renamed CFLAGS to KBUILD_CFLAGS. Commit 222d394d30e7 ("kbuild: enable 'make AFLAGS=...' to add additional options to AS") renamed AFLAGS to KBUILD_AFLAGS. Commit 06c5040cdb13 ("kbuild: enable 'make CPPFLAGS=...' to add additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS. For some reason, LDFLAGS was not renamed. Using a well-known variable like LDFLAGS may result in accidental override of the variable. Kbuild generally uses KBUILD_ prefixed variables for the internally appended options, so here is one more conversion to sanitize the naming convention. I did not touch Makefiles under tools/ since the tools build system is a different world. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-23Merge branch 'tlb-fixes'Linus Torvalds10-163/+96
Merge fixes for missing TLB shootdowns. This fixes a couple of cases that involved us possibly freeing page table structures before the required TLB shootdown had been done. There are a few cleanup patches to make the code easier to follow, and to avoid some of the more problematic cases entirely when not necessary. To make this easier for backports, it undoes the recent lazy TLB patches, because the cleanups and fixes are more important, and Rik is ok with re-doing them later when things have calmed down. The missing TLB flush was only delayed, and the wrong ordering only happened under memory pressure (and in theory under a couple of other fairly theoretical situations), so this may have been all very unlikely to have hit people in practice. But getting the TLB shootdown wrong is _so_ hard to debug and see that I consider this a crticial fix. Many thanks to Jann Horn for having debugged this. * tlb-fixes: x86/mm: Only use tlb_remove_table() for paravirt mm: mmu_notifier fix for tlb_end_vma mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE mm/tlb: Remove tlb_remove_table() non-concurrent condition mm: move tlb_table_flush to tlb_flush_mmu_free x86/mm/tlb: Revert the recent lazy TLB patches
2018-08-23Merge tag 'for-linus-4.19b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tipLinus Torvalds6-159/+23
Pull xen fixes and cleanups from Juergen Gross: "Some cleanups, some minor fixes and a fix for a bug introduced in this merge window hitting 32-bit PV guests" * tag 'for-linus-4.19b-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: enable early use of set_fixmap in 32-bit Xen PV guest xen: remove unused hypercall functions x86/xen: remove unused function xen_auto_xlated_memory_setup() xen/ACPI: don't upload Px/Cx data for disabled processors x86/Xen: further refine add_preferred_console() invocations xen/mcelog: eliminate redundant setting of interface version x86/Xen: mark xen_setup_gdt() __init
2018-08-23x86/mm: Only use tlb_remove_table() for paravirtPeter Zijlstra9-6/+26
If we don't use paravirt; don't play unnecessary and complicated games to free page-tables. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rik van Riel <riel@surriel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-23mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREEPeter Zijlstra1-0/+1
Jann reported that x86 was missing required TLB invalidates when he hit the !*batch slow path in tlb_remove_table(). This is indeed the case; RCU_TABLE_FREE does not provide TLB (cache) invalidates, the PowerPC-hash where this code originated and the Sparc-hash where this was subsequently used did not need that. ARM which later used this put an explicit TLB invalidate in their __p*_free_tlb() functions, and PowerPC-radix followed that example. But when we hooked up x86 we failed to consider this. Fix this by (optionally) hooking tlb_remove_table() into the TLB invalidate code. NOTE: s390 was also needing something like this and might now be able to use the generic code again. [ Modified to be on top of Nick's cleanups, which simplified this patch now that tlb_flush_mmu_tlbonly() really only flushes the TLB - Linus ] Fixes: 9e52fc2b50de ("x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rik van Riel <riel@surriel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: Will Deacon <will.deacon@arm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22x86/mm/tlb: Revert the recent lazy TLB patchesPeter Zijlstra2-157/+69
Revert commits: 95b0e6357d3e x86/mm/tlb: Always use lazy TLB mode 64482aafe55f x86/mm/tlb: Only send page table free TLB flush to lazy TLB CPUs ac0315896970 x86/mm/tlb: Make lazy TLB mode lazier 61d0beb5796a x86/mm/tlb: Restructure switch_mm_irqs_off() 2ff6ddf19c0e x86/mm/tlb: Leave lazy TLB mode at page table free time In order to simplify the TLB invalidate fixes for x86 and unify the parts that need backporting. We'll try again later. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Rik van Riel <riel@surriel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds4-26/+61
Pull second set of KVM updates from Paolo Bonzini: "ARM: - Support for Group0 interrupts in guests - Cache management optimizations for ARMv8.4 systems - Userspace interface for RAS - Fault path optimization - Emulated physical timer fixes - Random cleanups x86: - fixes for L1TF - a new test case - non-support for SGX (inject the right exception in the guest) - fix lockdep false positive" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (49 commits) KVM: VMX: fixes for vmentry_l1d_flush module parameter kvm: selftest: add dirty logging test kvm: selftest: pass in extra memory when create vm kvm: selftest: include the tools headers kvm: selftest: unify the guest port macros tools: introduce test_and_clear_bit KVM: x86: SVM: Call x86_spec_ctrl_set_guest/host() with interrupts disabled KVM: vmx: Inject #UD for SGX ENCLS instruction in guest KVM: vmx: Add defines for SGX ENCLS exiting x86/kvm/vmx: Fix coding style in vmx_setup_l1d_flush() x86: kvm: avoid unused variable warning KVM: Documentation: rename the capability of KVM_CAP_ARM_SET_SERROR_ESR KVM: arm/arm64: Skip updating PTE entry if no change KVM: arm/arm64: Skip updating PMD entry if no change KVM: arm: Use true and false for boolean values KVM: arm/arm64: vgic: Do not use spin_lock_irqsave/restore with irq disabled KVM: arm/arm64: vgic: Move DEBUG_SPINLOCK_BUG_ON to vgic.h KVM: arm: vgic-v3: Add support for ICC_SGI0R and ICC_ASGI1R accesses KVM: arm64: vgic-v3: Add support for ICC_SGI0R_EL1 and ICC_ASGI1R_EL1 accesses KVM: arm/arm64: vgic-v3: Add core support for Group0 SGIs ...
2018-08-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds5-11/+8
Merge more updates from Andrew Morton: - the rest of MM - procfs updates - various misc things - more y2038 fixes - get_maintainer updates - lib/ updates - checkpatch updates - various epoll updates - autofs updates - hfsplus - some reiserfs work - fatfs updates - signal.c cleanups - ipc/ updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits) ipc/util.c: update return value of ipc_getref from int to bool ipc/util.c: further variable name cleanups ipc: simplify ipc initialization ipc: get rid of ids->tables_initialized hack lib/rhashtable: guarantee initial hashtable allocation lib/rhashtable: simplify bucket_table_alloc() ipc: drop ipc_lock() ipc/util.c: correct comment in ipc_obtain_object_check ipc: rename ipcctl_pre_down_nolock() ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid() ipc: reorganize initialization of kern_ipc_perm.seq ipc: compute kern_ipc_perm.id under the ipc lock init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp adfs: use timespec64 for time conversion kernel/sysctl.c: fix typos in comments drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md fork: don't copy inconsistent signal handler state to child signal: make get_signal() return bool signal: make sigkill_pending() return bool ...
2018-08-22module: use relative references for __ksymtab entriesArd Biesheuvel2-5/+1
An ordinary arm64 defconfig build has ~64 KB worth of __ksymtab entries, each consisting of two 64-bit fields containing absolute references, to the symbol itself and to a char array containing its name, respectively. When we build the same configuration with KASLR enabled, we end up with an additional ~192 KB of relocations in the .init section, i.e., one 24 byte entry for each absolute reference, which all need to be processed at boot time. Given how the struct kernel_symbol that describes each entry is completely local to module.c (except for the references emitted by EXPORT_SYMBOL() itself), we can easily modify it to contain two 32-bit relative references instead. This reduces the size of the __ksymtab section by 50% for all 64-bit architectures, and gets rid of the runtime relocations entirely for architectures implementing KASLR, either via standard PIE linking (arm64) or using custom host tools (x86). Note that the binary search involving __ksymtab contents relies on each section being sorted by symbol name. This is implemented based on the input section names, not the names in the ksymtab entries, so this patch does not interfere with that. Given that the use of place-relative relocations requires support both in the toolchain and in the module loader, we cannot enable this feature for all architectures. So make it dependent on whether CONFIG_HAVE_ARCH_PREL32_RELOCATIONS is defined. Link: http://lkml.kernel.org/r/20180704083651.24360-4-ard.biesheuvel@linaro.org Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morris <james.morris@microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22module: allow symbol exports to be disabledArd Biesheuvel1-4/+1
To allow existing C code to be incorporated into the decompressor or the UEFI stub, introduce a CPP macro that turns all EXPORT_SYMBOL_xxx declarations into nops, and #define it in places where such exports are undesirable. Note that this gets rid of a rather dodgy redefine of linux/export.h's header guard. Link: http://lkml.kernel.org/r/20180704083651.24360-3-ard.biesheuvel@linaro.org Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morris <james.morris@microsoft.com> Cc: James Morris <jmorris@namei.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Russell King <linux@armlinux.org.uk> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22arch: enable relative relocations for arm64, power and x86Ard Biesheuvel1-0/+1
Patch series "add support for relative references in special sections", v10. This adds support for emitting special sections such as initcall arrays, PCI fixups and tracepoints as relative references rather than absolute references. This reduces the size by 50% on 64-bit architectures, but more importantly, it removes the need for carrying relocation metadata for these sections in relocatable kernels (e.g., for KASLR) that needs to be fixed up at boot time. On arm64, this reduces the vmlinux footprint of such a reference by 8x (8 byte absolute reference + 24 byte RELA entry vs 4 byte relative reference) Patch #3 was sent out before as a single patch. This series supersedes the previous submission. This version makes relative ksymtab entries dependent on the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS rather than trying to infer from kbuild test robot replies for which architectures it should be blacklisted. Patch #1 introduces the new Kconfig symbol HAVE_ARCH_PREL32_RELOCATIONS, and sets it for the main architectures that are expected to benefit the most from this feature, i.e., 64-bit architectures or ones that use runtime relocations. Patch #2 add support for #define'ing __DISABLE_EXPORTS to get rid of ksymtab/kcrctab sections in decompressor and EFI stub objects when rebuilding existing C files to run in a different context. Patches #4 - #6 implement relative references for initcalls, PCI fixups and tracepoints, respectively, all of which produce sections with order ~1000 entries on an arm64 defconfig kernel with tracing enabled. This means we save about 28 KB of vmlinux space for each of these patches. [From the v7 series blurb, which included the jump_label patches as well]: For the arm64 kernel, all patches combined reduce the memory footprint of vmlinux by about 1.3 MB (using a config copied from Ubuntu that has KASLR enabled), of which ~1 MB is the size reduction of the RELA section in .init, and the remaining 300 KB is reduction of .text/.data. This patch (of 6): Before updating certain subsystems to use place relative 32-bit relocations in special sections, to save space and reduce the number of absolute relocations that need to be processed at runtime by relocatable kernels, introduce the Kconfig symbol and define it for some architectures that should be able to support and benefit from it. Link: http://lkml.kernel.org/r/20180704083651.24360-2-ard.biesheuvel@linaro.org Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Will Deacon <will.deacon@arm.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Petr Mladek <pmladek@suse.com> Cc: James Morris <jmorris@namei.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>, Cc: James Morris <james.morris@microsoft.com> Cc: Jessica Yu <jeyu@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22mm, oom: distinguish blockable mode for mmu notifiersMichal Hocko1-2/+5
There are several blockable mmu notifiers which might sleep in mmu_notifier_invalidate_range_start and that is a problem for the oom_reaper because it needs to guarantee a forward progress so it cannot depend on any sleepable locks. Currently we simply back off and mark an oom victim with blockable mmu notifiers as done after a short sleep. That can result in selecting a new oom victim prematurely because the previous one still hasn't torn its memory down yet. We can do much better though. Even if mmu notifiers use sleepable locks there is no reason to automatically assume those locks are held. Moreover majority of notifiers only care about a portion of the address space and there is absolutely zero reason to fail when we are unmapping an unrelated range. Many notifiers do really block and wait for HW which is harder to handle and we have to bail out though. This patch handles the low hanging fruit. __mmu_notifier_invalidate_range_start gets a blockable flag and callbacks are not allowed to sleep if the flag is set to false. This is achieved by using trylock instead of the sleepable lock for most callbacks and continue as long as we do not block down the call chain. I think we can improve that even further because there is a common pattern to do a range lookup first and then do something about that. The first part can be done without a sleeping lock in most cases AFAICS. The oom_reaper end then simply retries if there is at least one notifier which couldn't make any progress in !blockable mode. A retry loop is already implemented to wait for the mmap_sem and this is basically the same thing. The simplest way for driver developers to test this code path is to wrap userspace code which uses these notifiers into a memcg and set the hard limit to hit the oom. This can be done e.g. after the test faults in all the mmu notifier managed memory and set the hard limit to something really small. Then we are looking for a proper process tear down. [akpm@linux-foundation.org: coding style fixes] [akpm@linux-foundation.org: minor code simplification] Link: http://lkml.kernel.org/r/20180716115058.5559-1-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Christian König <christian.koenig@amd.com> # AMD notifiers Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx and umem_odp Reported-by: David Rientjes <rientjes@google.com> Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: David Airlie <airlied@linux.ie> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Doug Ledford <dledford@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Mike Marciniszyn <mike.marciniszyn@intel.com> Cc: Dennis Dalessandro <dennis.dalessandro@intel.com> Cc: Sudeep Dutt <sudeep.dutt@intel.com> Cc: Ashutosh Dixit <ashutosh.dixit@intel.com> Cc: Dimitri Sivanich <sivanich@sgi.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Felix Kuehling <felix.kuehling@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22KVM: VMX: fixes for vmentry_l1d_flush module parameterPaolo Bonzini1-10/+16
Two bug fixes: 1) missing entries in the l1d_param array; this can cause a host crash if an access attempts to reach the missing entry. Future-proof the get function against any overflows as well. However, the two entries VMENTER_L1D_FLUSH_EPT_DISABLED and VMENTER_L1D_FLUSH_NOT_REQUIRED must not be accepted by the parse function, so disable them there. 2) invalid values must be rejected even if the CPU does not have the bug, so test for them before checking boot_cpu_has(X86_BUG_L1TF) ... and a small refactoring, since the .cmd field is redundant with the index in the array. Reported-by: Bandan Das <bsd@redhat.com> Cc: stable@vger.kernel.org Fixes: a7b9020b06ec6d7c3f3b0d4ef1a9eba12654f4f7 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22KVM: x86: SVM: Call x86_spec_ctrl_set_guest/host() with interrupts disabledThomas Gleixner1-4/+4
Mikhail reported the following lockdep splat: WARNING: possible irq lock inversion dependency detected CPU 0/KVM/10284 just changed the state of lock: 000000000d538a88 (&st->lock){+...}, at: speculative_store_bypass_update+0x10b/0x170 but this lock was taken by another, HARDIRQ-safe lock in the past: (&(&sighand->siglock)->rlock){-.-.} and interrupts could create inverse lock ordering between them. Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&st->lock); local_irq_disable(); lock(&(&sighand->siglock)->rlock); lock(&st->lock); <Interrupt> lock(&(&sighand->siglock)->rlock); *** DEADLOCK *** The code path which connects those locks is: speculative_store_bypass_update() ssb_prctl_set() do_seccomp() do_syscall_64() In svm_vcpu_run() speculative_store_bypass_update() is called with interupts enabled via x86_virt_spec_ctrl_set_guest/host(). This is actually a false positive, because GIF=0 so interrupts are disabled even if IF=1; however, we can easily move the invocations of x86_virt_spec_ctrl_set_guest/host() into the interrupt disabled region to cure it, and it's a good idea to keep the GIF=0/IF=1 area as small and self-contained as possible. Fixes: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD") Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: kvm@vger.kernel.org Cc: x86@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22KVM: vmx: Inject #UD for SGX ENCLS instruction in guestSean Christopherson1-1/+29
Virtualization of Intel SGX depends on Enclave Page Cache (EPC) management that is not yet available in the kernel, i.e. KVM support for exposing SGX to a guest cannot be added until basic support for SGX is upstreamed, which is a WIP[1]. Until SGX is properly supported in KVM, ensure a guest sees expected behavior for ENCLS, i.e. all ENCLS #UD. Because SGX does not have a true software enable bit, e.g. there is no CR4.SGXE bit, the ENCLS instruction can be executed[1] by the guest if SGX is supported by the system. Intercept all ENCLS leafs (via the ENCLS- exiting control and field) and unconditionally inject #UD. [1] https://www.spinics.net/lists/kvm/msg171333.html or https://lkml.org/lkml/2018/7/3/879 [2] A guest can execute ENCLS in the sense that ENCLS will not take an immediate #UD, but no ENCLS will ever succeed in a guest without explicit support from KVM (map EPC memory into the guest), unless KVM has a *very* egregious bug, e.g. accidentally mapped EPC memory into the guest SPTEs. In other words this patch is needed only to prevent the guest from seeing inconsistent behavior, e.g. #GP (SGX not enabled in Feature Control MSR) or #PF (leaf operand(s) does not point at EPC memory) instead of #UD on ENCLS. Intercepting ENCLS is not required to prevent the guest from truly utilizing SGX. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20180814163334.25724-3-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22KVM: vmx: Add defines for SGX ENCLS exitingSean Christopherson1-0/+3
Hardware support for basic SGX virtualization adds a new execution control (ENCLS_EXITING), VMCS field (ENCLS_EXITING_BITMAP) and exit reason (ENCLS), that enables a VMM to intercept specific ENCLS leaf functions, e.g. to inject faults when the VMM isn't exposing SGX to a VM. When ENCLS_EXITING is enabled, the VMM can set/clear bits in the bitmap to intercept/allow ENCLS leaf functions in non-root, e.g. setting bit 2 in the ENCLS_EXITING_BITMAP will cause ENCLS[EINIT] to VMExit(ENCLS). Note: EXIT_REASON_ENCLS was previously added by commit 1f5199927034 ("KVM: VMX: add missing exit reasons"). Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20180814163334.25724-2-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22x86/kvm/vmx: Fix coding style in vmx_setup_l1d_flush()Yi Wang1-9/+9
Substitute spaces with tab. No functional changes. Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Message-Id: <1534398159-48509-1-git-send-email-wang.yi59@zte.com.cn> Cc: stable@vger.kernel.org # L1TF Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22x86: kvm: avoid unused variable warningArnd Bergmann1-3/+1
Removing one of the two accesses of the maxphyaddr variable led to a harmless warning: arch/x86/kvm/x86.c: In function 'kvm_set_mmio_spte_mask': arch/x86/kvm/x86.c:6563:6: error: unused variable 'maxphyaddr' [-Werror=unused-variable] Removing the #ifdef seems to be the nicest workaround, as it makes the code look cleaner than adding another #ifdef. Fixes: 28a1f3ac1d0c ("kvm: x86: Set highest physical address bits in non-present/reserved SPTEs") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: stable@vger.kernel.org # L1TF Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-22Merge tag 'pm-4.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds1-1/+1
Pull more power management updates from Rafael Wysocki: "These fix the main idle loop and the menu cpuidle governor, clean up the latter, fix a mistake in the PCI bus type's support for system suspend and resume, fix the ondemand and conservative cpufreq governors, address a build issue in the system wakeup framework and make the ACPI C-states desciptions less confusing. Specifics: - Make the idle loop handle stopped scheduler tick correctly (Rafael Wysocki). - Prevent the menu cpuidle governor from letting CPUs spend too much time in shallow idle states when it is invoked with scheduler tick stopped and clean it up somewhat (Rafael Wysocki). - Avoid invoking the platform firmware to make the platform enter the ACPI S3 sleep state with suspended PCIe root ports which may confuse the firmware and cause it to crash (Rafael Wysocki). - Fix sysfs-related race in the ondemand and conservative cpufreq governors which may cause the system to crash if the governor module is removed during an update of CPU frequency limits (Henry Willard). - Select SRCU when building the system wakeup framework to avoid a build issue in it (zhangyi). - Make the descriptions of ACPI C-states vendor-neutral to avoid confusion (Prarit Bhargava)" * tag 'pm-4.19-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpuidle: menu: Handle stopped tick more aggressively sched: idle: Avoid retaining the tick when it has been stopped PCI / ACPI / PM: Resume all bridges on suspend-to-RAM cpuidle: menu: Update stale polling override comment cpufreq: governor: Avoid accessing invalid governor_data x86/ACPI/cstate: Make APCI C1 FFH MWAIT C-state description vendor-neutral cpuidle: menu: Fix white space PM / sleep: wakeup: Fix build error caused by missing SRCU support
2018-08-20x86/xen: enable early use of set_fixmap in 32-bit Xen PV guestJuergen Gross3-5/+16
Commit 7b25b9cb0dad83 ("x86/xen/time: Initialize pv xen time in init_hypervisor_platform()") moved the mapping of the shared info area before pagetable_init(). This breaks booting as 32-bit PV guest as the use of set_fixmap isn't possible at this time on 32-bit. This can be worked around by populating the needed PMD on 32-bit kernel earlier. In order not to reimplement populate_extra_pte() using extend_brk() for allocating new page tables extend alloc_low_pages() to do that in case the early page table pool is not yet available. Fixes: 7b25b9cb0dad83 ("x86/xen/time: Initialize pv xen time in init_hypervisor_platform()") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-08-20xen: remove unused hypercall functionsJuergen Gross1-118/+0
Remove Xen hypercall functions which are used nowhere in the kernel. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>