kernel/linux.git/arch/x86/power, branch linux-4.16.y

x86/power: Fix swsusp_arch_resume prototype

2018-02-02T22:33:50+00:00

The declaration for swsusp_arch_resume marks it as 'asmlinkage', but the definition in x86-32 does not, and it fails to include the header with the declaration. This leads to a warning when building with link-time-optimizations: kernel/power/power.h:108:23: error: type of 'swsusp_arch_resume' does not match original declaration [-Werror=lto-type-mismatch] extern asmlinkage int swsusp_arch_resume(void); ^ arch/x86/power/hibernate_32.c:148:0: note: 'swsusp_arch_resume' was previously declared here int swsusp_arch_resume(void) This moves the declaration into a globally visible header file and fixes up both x86 definitions to match it. Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Gleixner Cc: Len Brown Cc: Andi Kleen Cc: Nicolas Pitre Cc: linux-pm@vger.kernel.org Cc: "Rafael J. Wysocki" Cc: Pavel Machek Cc: Bart Van Assche Link: https://lkml.kernel.org/r/20180202145634.200291-2-arnd@arndb.de

Merge branch 'WIP.x86-pti.entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-12-18T16:59:15+00:00

Pull x86 syscall entry code changes for PTI from Ingo Molnar: "The main changes here are Andy Lutomirski's changes to switch the x86-64 entry code to use the 'per CPU entry trampoline stack'. This, besides helping fix KASLR leaks (the pending Page Table Isolation (PTI) work), also robustifies the x86 entry code" * 'WIP.x86-pti.entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) x86/cpufeatures: Make CPU bugs sticky x86/paravirt: Provide a way to check for hypervisors x86/paravirt: Dont patch flush_tlb_single x86/entry/64: Make cpu_entry_area.tss read-only x86/entry: Clean up the SYSENTER_stack code x86/entry/64: Remove the SYSENTER stack canary x86/entry/64: Move the IST stacks into struct cpu_entry_area x86/entry/64: Create a per-CPU SYSCALL entry trampoline x86/entry/64: Return to userspace from the trampoline stack x86/entry/64: Use a per-CPU trampoline stack for IDT entries x86/espfix/64: Stop assuming that pt_regs is on the entry stack x86/entry/64: Separate cpu_current_top_of_stack from TSS.sp0 x86/entry: Remap the TSS into the CPU entry area x86/entry: Move SYSENTER_stack to the beginning of struct tss_struct x86/dumpstack: Handle stack overflow on all stacks x86/entry: Fix assumptions that the HW TSS is at the beginning of cpu_tss x86/kasan/64: Teach KASAN about the cpu_entry_area x86/mm/fixmap: Generalize the GDT fixmap mechanism, introduce struct cpu_entry_area x86/entry/gdt: Put per-CPU GDT remaps in ascending order x86/dumpstack: Add get_stack_info() support for the SYSENTER stack ...

x86/entry: Remap the TSS into the CPU entry area

2017-12-17T12:59:56+00:00

This has a secondary purpose: it puts the entry stack into a region with a well-controlled layout. A subsequent patch will take advantage of this to streamline the SYSCALL entry code to be able to find it more easily. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150605.962042855@linutronix.de Signed-off-by: Ingo Molnar

x86/entry: Fix assumptions that the HW TSS is at the beginning of cpu_tss

2017-12-17T12:59:55+00:00

A future patch will move SYSENTER_stack to the beginning of cpu_tss to help detect overflow. Before this can happen, fix several code paths that hardcode assumptions about the old layout. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov Reviewed-by: Dave Hansen Reviewed-by: Thomas Gleixner Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Link: https://lkml.kernel.org/r/20171204150605.722425540@linutronix.de Signed-off-by: Ingo Molnar

x86/power: Make restore_processor_context() sane

2017-12-15T11:21:38+00:00

My previous attempt to fix a couple of bugs in __restore_processor_context(): 5b06bbcfc2c6 ("x86/power: Fix some ordering bugs in __restore_processor_context()") ... introduced yet another bug, breaking suspend-resume. Rather than trying to come up with a minimal fix, let's try to clean it up for real. This patch fixes quite a few things: - The old code saved a nonsensical subset of segment registers. The only registers that need to be saved are those that contain userspace state or those that can't be trivially restored without percpu access working. (On x86_32, we can restore percpu access by writing __KERNEL_PERCPU to %fs. On x86_64, it's easier to save and restore the kernel's GSBASE.) With this patch, we restore hardcoded values to the kernel state where applicable and explicitly restore the user state after fixing all the descriptor tables. - We used to use an unholy mix of inline asm and C helpers for segment register access. Let's get rid of the inline asm. This fixes the reported s2ram hangs and make the code all around more logical. Analyzed-by: Linus Torvalds Reported-by: Jarkko Nikula Reported-by: Pavel Machek Tested-by: Jarkko Nikula Tested-by: Pavel Machek Signed-off-by: Andy Lutomirski Acked-by: Rafael J. Wysocki Acked-by: Thomas Gleixner Cc: Borislav Petkov Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Zhang Rui Fixes: 5b06bbcfc2c6 ("x86/power: Fix some ordering bugs in __restore_processor_context()") Link: http://lkml.kernel.org/r/398ee68e5c0f766425a7b746becfc810840770ff.1513286253.git.luto@kernel.org Signed-off-by: Ingo Molnar

x86/power/32: Move SYSENTER MSR restoration to fix_processor_context()

2017-12-15T11:18:29+00:00

x86_64 restores system call MSRs in fix_processor_context(), and x86_32 restored them along with segment registers. The 64-bit variant makes more sense, so move the 32-bit code to match the 64-bit code. No side effects are expected to runtime behavior. Tested-by: Jarkko Nikula Signed-off-by: Andy Lutomirski Acked-by: Rafael J. Wysocki Acked-by: Thomas Gleixner Cc: Borislav Petkov Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Pavel Machek Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Zhang Rui Link: http://lkml.kernel.org/r/65158f8d7ee64dd6bbc6c1c83b3b34aaa854e3ae.1513286253.git.luto@kernel.org Signed-off-by: Ingo Molnar

x86/power/64: Use struct desc_ptr for the IDT in struct saved_context

2017-12-15T11:18:29+00:00

x86_64's saved_context nonsensically used separate idt_limit and idt_base fields and then cast &idt_limit to struct desc_ptr *. This was correct (with -fno-strict-aliasing), but it's confusing, served no purpose, and required #ifdeffery. Simplify this by using struct desc_ptr directly. No change in functionality. Tested-by: Jarkko Nikula Signed-off-by: Andy Lutomirski Acked-by: Rafael J. Wysocki Acked-by: Thomas Gleixner Cc: Borislav Petkov Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Pavel Machek Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Zhang Rui Link: http://lkml.kernel.org/r/967909ce38d341b01d45eff53e278e2728a3a93a.1513286253.git.luto@kernel.org Signed-off-by: Ingo Molnar

x86/power: Fix some ordering bugs in __restore_processor_context()

2017-12-06T11:29:12+00:00

__restore_processor_context() had a couple of ordering bugs. It restored GSBASE after calling load_gs_index(), and the latter can call into tracing code. It also tried to restore segment registers before restoring the LDT, which is straight-up wrong. Reorder the code so that we restore GSBASE, then the descriptor tables, then the segments. This fixes two bugs. First, it fixes a regression that broke resume under certain configurations due to irqflag tracing in native_load_gs_index(). Second, it fixes resume when the userspace process that initiated suspect had funny segments. The latter can be reproduced by compiling this: // SPDX-License-Identifier: GPL-2.0 /* * ldt_echo.c - Echo argv[1] while using an LDT segment */ int main(int argc, char **argv) { int ret; size_t len; char *buf; const struct user_desc desc = { .entry_number = 0, .base_addr = 0, .limit = 0xfffff, .seg_32bit = 1, .contents = 0, /* Data, grow-up */ .read_exec_only = 0, .limit_in_pages = 1, .seg_not_present = 0, .useable = 0 }; if (argc != 2) errx(1, "Usage: %s STRING", argv[0]); len = asprintf(&buf, "%s\n", argv[1]); if (len < 0) errx(1, "Out of memory"); ret = syscall(SYS_modify_ldt, 1, &desc, sizeof(desc)); if (ret < -1) errno = -ret; if (ret) err(1, "modify_ldt"); asm volatile ("movw %0, %%es" :: "rm" ((unsigned short)7)); write(1, buf, len); return 0; } and running ldt_echo >/sys/power/mem Without the fix, the latter causes a triple fault on resume. Fixes: ca37e57bbe0c ("x86/entry/64: Add missing irqflags tracing to native_load_gs_index()") Reported-by: Jarkko Nikula Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Tested-by: Jarkko Nikula Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Linus Torvalds Link: https://lkml.kernel.org/r/6b31721ea92f51ea839e79bd97ade4a75b1eeea2.1512057304.git.luto@kernel.org Signed-off-by: Ingo Molnar

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

dmi: Mark all struct dmi_system_id instances const

2017-09-14T09:59:30+00:00

... and __initconst if applicable. Based on similar work for an older kernel in the Grsecurity patch. [JD: fix toshiba-wmi build] [JD: add htcpen] [JD: move __initconst where checkscript wants it] Signed-off-by: Christoph Hellwig Signed-off-by: Jean Delvare