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2022-01-12Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+1
Pull x86 core updates from Borislav Petkov: - Get rid of all the .fixup sections because this generates misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and LIVEPATCH as the backtrace misses the function which is being fixed up. - Add Straight Line Speculation mitigation support which uses a new compiler switch -mharden-sls= which sticks an INT3 after a RET or an indirect branch in order to block speculation after them. Reportedly, CPUs do speculate behind such insns. - The usual set of cleanups and improvements * tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) x86/entry_32: Fix segment exceptions objtool: Remove .fixup handling x86: Remove .fixup section x86/word-at-a-time: Remove .fixup usage x86/usercopy: Remove .fixup usage x86/usercopy_32: Simplify __copy_user_intel_nocache() x86/sgx: Remove .fixup usage x86/checksum_32: Remove .fixup usage x86/vmx: Remove .fixup usage x86/kvm: Remove .fixup usage x86/segment: Remove .fixup usage x86/fpu: Remove .fixup usage x86/xen: Remove .fixup usage x86/uaccess: Remove .fixup usage x86/futex: Remove .fixup usage x86/msr: Remove .fixup usage x86/extable: Extend extable functionality x86/entry_32: Remove .fixup usage x86/entry_64: Remove .fixup usage x86/copy_mc_64: Remove .fixup usage ...
2021-12-08x86: Prepare asm files for straight-line-speculationPeter Zijlstra1-1/+1
Replace all ret/retq instructions with RET in preparation of making RET a macro. Since AS is case insensitive it's a big no-op without RET defined. find arch/x86/ -name \*.S | while read file do sed -i 's/\<ret[q]*\>/RET/' $file done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-11-21efi/libstub: x86/mixed: increase supported argument countArd Biesheuvel1-3/+11
Increase the number of arguments supported by mixed mode calls, so that we will be able to call into the TCG2 protocol to measure the initrd and extend the associated PCR. This involves the TCG2 protocol's hash_log_extend_event() method, which takes five arguments, three of which are u64 and need to be split, producing a total of 8 outgoing Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Link: https://lore.kernel.org/r/20211119114745.1560453-3-ilias.apalodimas@linaro.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-08-21x86/efi: Restore Firmware IDT before calling ExitBootServices()Joerg Roedel1-9/+21
Commit 79419e13e808 ("x86/boot/compressed/64: Setup IDT in startup_32 boot path") introduced an IDT into the 32-bit boot path of the decompressor stub. But the IDT is set up before ExitBootServices() is called, and some UEFI firmwares rely on their own IDT. Save the firmware IDT on boot and restore it before calling into EFI functions to fix boot failures introduced by above commit. Fixes: 79419e13e808 ("x86/boot/compressed/64: Setup IDT in startup_32 boot path") Reported-by: Fabio Aiuto <fabioaiuto83@gmail.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Ard Biesheuvel <ardb@kernel.org> Cc: stable@vger.kernel.org # 5.13+ Link: https://lkml.kernel.org/r/20210820125703.32410-1-joro@8bytes.org
2021-03-21x86: Fix various typos in comments, take #2Ingo Molnar1-1/+1
Fix another ~42 single-word typos in arch/x86/ code comments, missed a few in the first pass, in particular in .S files. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-kernel@vger.kernel.org
2020-05-24efi/x86: Drop the special GDT for the EFI thunkArvind Sankar1-16/+3
Instead of using efi_gdt64 to switch back to 64-bit mode and then switching to the real boot-time GDT, just switch to the boot-time GDT directly. The two GDT's are identical other than efi_gdt64 not including the 32-bit code segment. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200523221513.1642948-1-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/x86: Don't depend on firmware GDT layoutArvind Sankar1-5/+24
When booting in mixed mode, the firmware's GDT is still installed at handover entry in efi32_stub_entry. We save the GDTR for later use in __efi64_thunk but we are assuming that descriptor 2 (__KERNEL_CS) is a valid 32-bit code segment descriptor and that descriptor 3 (__KERNEL_DS/__BOOT_DS) is a valid data segment descriptor. This happens to be true for OVMF (it actually uses descriptor 1 for data segments, but descriptor 3 is also setup as data), but we shouldn't depend on this being the case. Fix this by saving the code and data selectors in addition to the GDTR in efi32_stub_entry, and restoring them in __efi64_thunk before calling the firmware. The UEFI specification guarantees that selectors will be flat, so using the DS selector for all the segment registers should be enough. We also need to install our own GDT before initializing segment registers in startup_32, so move the GDT load up to the beginning of the function. [ardb: mention mixed mode in the commit log] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-3-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-01-20efi/libstub/x86: Use mandatory 16-byte stack alignment in mixed modeArd Biesheuvel1-33/+13
Reduce the stack frame of the EFI stub's mixed mode thunk routine by 8 bytes, by moving the GDT and return addresses to EBP and EBX, which we need to preserve anyway, since their top halves will be cleared by the call into 32-bit firmware code. Doing so results in the UEFI code being entered with a 16 byte aligned stack, as mandated by the UEFI spec, fixing the last occurrence in the 64-bit kernel where we violate this requirement. Also, move the saved GDT from a global variable to an unused part of the stack frame, and touch up some other parts of the code. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200113172245.27925-3-ardb@kernel.org
2020-01-10efi/x86: Check number of arguments to variadic functionsArvind Sankar1-2/+2
On x86 we need to thunk through assembler stubs to call the EFI services for mixed mode, and for runtime services in 64-bit mode. The assembler stubs have limits on how many arguments it handles. Introduce a few macros to check that we do not try to pass too many arguments to the stubs. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Matthew Garrett <mjg59@google.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-16-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25efi/libstub/x86: Avoid globals to store context during mixed mode callsArd Biesheuvel1-14/+3
Instead of storing the return address in a global variable when calling a 32-bit EFI service from the 64-bit stub, avoid the indirection via efi_exit32, and take the return address from the stack. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Borislav Petkov <bp@alien8.de> Cc: James Morse <james.morse@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-26-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-18x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_*Jiri Slaby1-2/+2
These are all functions which are invoked from elsewhere, so annotate them as global using the new SYM_FUNC_START and their ENDPROC's by SYM_FUNC_END. Make sure ENTRY/ENDPROC is not defined on X86_64, given these were the last users. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [hibernate] Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [xen bits] Acked-by: Herbert Xu <herbert@gondor.apana.org.au> [crypto] Cc: Allison Randal <allison@lohutok.net> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andy Shevchenko <andy@infradead.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Armijn Hemel <armijn@tjaldur.nl> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Enrico Weigelt <info@metux.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jim Mattson <jmattson@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Len Brown <len.brown@intel.com> Cc: linux-arch@vger.kernel.org Cc: linux-crypto@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: linux-efi@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: platform-driver-x86@vger.kernel.org Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: Wei Huang <wei@redhat.com> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com> Link: https://lkml.kernel.org/r/20191011115108.12392-25-jslaby@suse.cz
2019-10-18x86/asm: Make some functions localJiri Slaby1-4/+4
There are a couple of assembly functions which are invoked only locally in the file they are defined. In C, they are marked "static". In assembly, annotate them using SYM_{FUNC,CODE}_START_LOCAL (and switch their ENDPROC to SYM_{FUNC,CODE}_END too). Whether FUNC or CODE is used, depends on whether ENDPROC or END was used for a particular function before. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andy Shevchenko <andy@infradead.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: linux-arch@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: linux-efi@vger.kernel.org Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: platform-driver-x86@vger.kernel.org Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20191011115108.12392-21-jslaby@suse.cz
2019-10-18x86/boot: Annotate data appropriatelyJiri Slaby1-9/+12
Use the new SYM_DATA, SYM_DATA_START, and SYM_DATA_END* macros for data, so that the data in the object file look sane: Value Size Type Bind Vis Ndx Name 0000 10 OBJECT GLOBAL DEFAULT 3 efi32_boot_gdt 000a 10 OBJECT LOCAL DEFAULT 3 save_gdt 0014 8 OBJECT LOCAL DEFAULT 3 func_rt_ptr 001c 48 OBJECT GLOBAL DEFAULT 3 efi_gdt64 004c 0 OBJECT LOCAL DEFAULT 3 efi_gdt64_end 0000 48 OBJECT LOCAL DEFAULT 3 gdt 0030 0 OBJECT LOCAL DEFAULT 3 gdt_end 0030 8 OBJECT LOCAL DEFAULT 3 efi_config 0038 49 OBJECT GLOBAL DEFAULT 3 efi32_config 0069 49 OBJECT GLOBAL DEFAULT 3 efi64_config All have correct size and type now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Allison Randal <allison@lohutok.net> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: Enrico Weigelt <info@metux.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: linux-arch@vger.kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Huang <wei@redhat.com> Cc: x86-ml <x86@kernel.org> Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com> Link: https://lkml.kernel.org/r/20191011115108.12392-13-jslaby@suse.cz
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-13x86/efi: Avoid triple faults during EFI mixed mode callsMatt Fleming1-0/+196
Andy pointed out that if an NMI or MCE is received while we're in the middle of an EFI mixed mode call a triple fault will occur. This can happen, for example, when issuing an EFI mixed mode call while running perf. The reason for the triple fault is that we execute the mixed mode call in 32-bit mode with paging disabled but with 64-bit kernel IDT handlers installed throughout the call. At Andy's suggestion, stop playing the games we currently do at runtime, such as disabling paging and installing a 32-bit GDT for __KERNEL_CS. We can simply switch to the __KERNEL32_CS descriptor before invoking firmware services, and run in compatibility mode. This way, if an NMI/MCE does occur the kernel IDT handler will execute correctly, since it'll jump to __KERNEL_CS automatically. However, this change is only possible post-ExitBootServices(). Before then the firmware "owns" the machine and expects for its 32-bit IDT handlers to be left intact to service interrupts, etc. So, we now need to distinguish between early boot and runtime invocations of EFI services. During early boot, we need to restore the GDT that the firmware expects to be present. We can only jump to the __KERNEL32_CS code segment for mixed mode calls after ExitBootServices() has been invoked. A liberal sprinkling of comments in the thunking code should make the differences in early and late environments more apparent. Reported-by: Andy Lutomirski <luto@amacapital.net> Tested-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>