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2017-04-12kprobes/x86: Set kprobes pages read-onlyMasami Hiramatsu
Set the pages which is used for kprobes' singlestep buffer and optprobe's trampoline instruction buffer to readonly. This can prevent unexpected (or unintended) instruction modification. This also passes rodata_test as below. Without this patch, rodata_test shows a warning: WARNING: CPU: 0 PID: 1 at arch/x86/mm/dump_pagetables.c:235 note_page+0x7a9/0xa20 x86/mm: Found insecure W+X mapping at address ffffffffa0000000/0xffffffffa0000000 With this fix, no W+X pages are found: x86/mm: Checked W+X mappings: passed, no W+X pages found. rodata_test: all tests were successful Reported-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076375592.22469.14174394514338612247.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12kprobes/x86: Make boostable flag booleanMasami Hiramatsu
Make arch_specific_insn.boostable to boolean, since it has only 2 states, boostable or not. So it is better to use boolean from the viewpoint of code readability. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076368566.22469.6322906866458231844.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12kprobes/x86: Do not modify singlestep buffer while resumingMasami Hiramatsu
Do not modify singlestep execution buffer (kprobe.ainsn.insn) while resuming from single-stepping, instead, modifies the buffer to add a jump back instruction at preparing buffer. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076361560.22469.1610155860343077495.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12kprobes/x86: Use instruction decoder for boosterMasami Hiramatsu
Use x86 instruction decoder for checking whether the probed instruction is able to boost or not, instead of hand-written code. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076354563.22469.13379472209338986858.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12kprobes/x86: Fix the description of __copy_instruction()Masami Hiramatsu
Fix the description comment of __copy_instruction() function since it has already been changed to return the length of the copied instruction. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076347582.22469.3775133607244923462.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-12kprobes/x86: Fix kprobe-booster not to boost far call instructionsMasami Hiramatsu
Fix the kprobe-booster not to boost far call instruction, because a call may store the address in the single-step execution buffer to the stack, which should be modified after single stepping. Currently, this instruction will be filtered as not boostable in resume_execution(), so this is not a critical issue. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David S . Miller <davem@davemloft.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ye Xiaolong <xiaolong.ye@intel.com> Link: http://lkml.kernel.org/r/149076340615.22469.14066273186134229909.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11Merge branch 'x86/urgent' into x86/cpu, to resolve conflictIngo Molnar
Conflicts: arch/x86/kernel/cpu/intel_rdt_schemata.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11x86/intel_rdt: Fix locking in rdtgroup_schemata_write()Jiri Olsa
The schemata lock is released before freeing the resource's temporary tmp_cbms allocation. That's racy versus another write which allocates and uses new temporary storage, resulting in memory leaks, freeing in use memory, double a free or any combination of those. Move the unlock after the release code. Fixes: 60ec2440c63d ("x86/intel_rdt: Add schemata file") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Shaohua Li <shli@fb.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170411071446.15241-1-jolsa@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-11x86/debug: Fix the printk() debug output of signal_fault(), do_trap() and ↵Markus Trippelsdorf
do_general_protection() Since commit: 4bcc595ccd80 "printk: reinstate KERN_CONT for printing" ... the debug output of signal_fault(), do_trap() and do_general_protection() looks garbled, e.g.: traps: conftest[9335] trap invalid opcode ip:400428 sp:7ffeaba1b0d8 error:0 in conftest[400000+1000] (note the unintended line break.) Fix the bug by adding KERN_CONTs. Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11Merge branch 'x86/boot' into x86/mm, to avoid conflictIngo Molnar
There's a conflict between ongoing level-5 paging support and the E820 rewrite. Since the E820 rewrite is essentially ready, merge it into x86/mm to reduce tree conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11Merge branch 'WIP.x86/boot' into x86/boot, to pick up ready branchIngo Molnar
The E820 rework in WIP.x86/boot has gone through a couple of weeks of exposure in -tip, merge it in a wider fashion. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11Backmerge tag 'v4.11-rc6' into drm-nextDave Airlie
Linux 4.11-rc6 drm-misc needs 4.11-rc5, may as well fix conflicts with rc6.
2017-04-10x86/intel_rdt: Add cpus_list rdtgroup fileJiri Olsa
The resource control filesystem provides only a bitmask based cpus file for assigning CPUs to a resource group. That's cumbersome with large cpumasks and non-intuitive when modifying the file from the command line. Range based cpu lists are commonly used along with bitmask based cpu files in various subsystems throughout the kernel. Add 'cpus_list' file which is CPU range based. # cd /sys/fs/resctrl/ # echo 1-10 > krava/cpus_list # cat krava/cpus_list 1-10 # cat krava/cpus 0007fe # cat cpus fffff9 # cat cpus_list 0,3-23 [ tglx: Massaged changelog and replaced "bitmask lists" by "CPU ranges" ] Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Shaohua Li <shli@fb.com> Link: http://lkml.kernel.org/r/20170410145232.GF25354@krava Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-10x86/nmi, EDAC: Get rid of DRAM error reporting thru PCI SERR NMIBorislav Petkov
Apparently, some machines used to report DRAM errors through a PCI SERR NMI. This is why we have a call into EDAC in the NMI handler. See c0d121720220 ("drivers/edac: add new nmi rescan"). From looking at the patch above, that's two drivers: e752x_edac.c and e7xxx_edac.c. Now, I wanna say those are old machines which are probably decommissioned already. Tony says that "[t]the newest CPU supported by either of those drivers is the Xeon E7520 (a.k.a. "Nehalem") released in Q1'2010. Possibly some folks are still using these ... but people that hold onto h/w for 7 years generally cling to old s/w too ... so I'd guess it unlikely that we will get complaints for breaking these in upstream." So even if there is a small number still in use, we did load EDAC with edac_op_state == EDAC_OPSTATE_POLL by default (we still do, in fact) which means a default EDAC setup without any parameters supplied on the command line or otherwise would never even log the error in the NMI handler because we're polling by default: inline int edac_handler_set(void) { if (edac_op_state == EDAC_OPSTATE_POLL) return 0; return atomic_read(&edac_handlers); } So, long story short, I'd like to get rid of that nastiness called edac_stub.c and confine all the EDAC drivers solely to drivers/edac/. If we ever have to do stuff like that again, it should be notifiers we're using and not some insanity like this one. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com>
2017-04-08Drivers: hv: Issue explicit EOI when autoeoi is not enabledK. Y. Srinivasan
When auto EOI is not enabled; issue an explicit EOI for hyper-v interrupts. Fixes: 6c248aad81c8 ("Drivers: hv: Base autoeoi enablement based on hypervisor hints") Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-05x86/intel_rdt: Update schemata read to show data in tabular formatVikas Shivappa
The schemata file displays data from different resources on all domains. Its cumbersome to read since they are not tabular and data/names could be of different widths. Make the schemata file to display data in a tabular format thereby making it nice and simple to read. Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: peterz@infradead.org Cc: vikas.shivappa@intel.com Cc: h.peter.anvin@intel.com Link: http://lkml.kernel.org/r/1491255857-17213-4-git-send-email-vikas.shivappa@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-05x86/intel_rdt: Implement "update" mode when writing schemata fileTony Luck
The schemata file can have multiple lines and it is cumbersome to update all lines. Remove code that requires that the user provides values for every resource (in the right order). If the user provides values for just a few resources, update them and leave the rest unchanged. Side benefit: we now check which values were updated and only send IPIs to cpus that actually have updates. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: ravi.v.shankar@intel.com Cc: fenghua.yu@intel.com Cc: peterz@infradead.org Cc: vikas.shivappa@intel.com Cc: h.peter.anvin@intel.com Link: http://lkml.kernel.org/r/1491255857-17213-3-git-send-email-vikas.shivappa@linux.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-05efi/bgrt: Enable ACPI BGRT handling on arm64Bhupesh Sharma
Now that the ACPI BGRT handling code has been made generic, we can enable it for arm64. Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com> [ Updated commit log to reflect that BGRT is only enabled for arm64, and added missing 'return' statement to the dummy acpi_parse_bgrt() function. ] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170404160245.27812-8-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-05x86/signals: Fix lower/upper bound reporting in compat siginfoJoerg Roedel
Put the right values from the original siginfo into the userspace compat-siginfo. This fixes the 32-bit MPX "tabletest" testcase on 64-bit kernels. Signed-off-by: Joerg Roedel <jroedel@suse.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: <stable@vger.kernel.org> # v4.8+ Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: a4455082dc6f0 ('x86/signals: Add missing signal_compat code for x86 features') Link: http://lkml.kernel.org/r/1491322501-5054-1-git-send-email-joro@8bytes.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-04x86/espfix: Add support for 5-level pagingKirill A. Shutemov
We don't need extra virtual address space for ESPFIX, so it stays within one PUD page table for both 4- and 5-level paging. Redefining ESPFIX_BASE_ADDR using P4D_SHIFT instead of PGDIR_SHIFT would make it stay in the same place regarding of paging mode. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170330080731.65421-8-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-04x86/paravirt: Add 5-level support to the paravirt codeKirill A. Shutemov
Add operations to allocate/release p4ds. Xen requires more work. We will need to come back to it. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170330080731.65421-5-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-03Merge branch 'ras-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RAS fix from Thomas Gleixner: "Prevent dmesg from being spammed when MCE logging is active" * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Don't print MCEs when mcelog is active
2017-04-03Merge tag 'v4.11-rc5' into x86/mm, to refresh the branchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-03debug: Fix __bug_table[] in arch linker scriptsPeter Zijlstra
The kbuild test robot reported this build failure on a number of architectures: > make.cross ARCH=arm > lib/lib.a(bug.o): In function `find_bug': > >> lib/bug.c:135: undefined reference to `__start___bug_table' > >> lib/bug.c:135: undefined reference to `__stop___bug_table' Caused by: 19d436268dde ("debug: Add _ONCE() logic to report_bug()") Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(), but a number of architectures don't use RW_DATA_SECTION(), so they ended up with no __bug_table[] ... Ideally all those would use RW_DATA_SECTION() in their linker scripts, but that's for another day. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kbuild test robot <fengguang.wu@intel.com> Cc: kbuild-all@01.org Cc: tipbuild@zytor.com Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-02Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "This update provides: - prevent KASLR from randomizing EFI regions - restrict the usage of -maccumulate-outgoing-args and document when and why it is required. - make the Global Physical Address calculation for UV4 systems work correctly. - address a copy->paste->forgot-edit problem in the MCE exception table entries. - assign a name to AMD MCA bank 3, so the sysfs file registration works. - add a missing include in the boot code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Include missing header file x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs x86/build: Mostly disable '-maccumulate-outgoing-args' x86/mm/KASLR: Exclude EFI region from KASLR VA space randomization x86/mce: Fix copy/paste error in exception table entries x86/platform/uv: Fix calculation of Global Physical Address
2017-03-31x86/mm: Make in_compat_syscall() work during execDmitry Safonov
The x86 mmap() code selects the mmap base for an allocation depending on the bitness of the syscall. For 64bit sycalls it select mm->mmap_base and for 32bit mm->mmap_compat_base. On execve the registers of the task invoking exec() are copied to the child pt_regs. So child->pt_regs->orig_ax contains the execve syscall number of the parent. exec() calls mmap() which in turn uses in_compat_syscall() to check whether the mapping is for a 32bit or a 64bit task. The decision is made on the following criteria: ia32 child->thread.status & TS_COMPAT x32 child->pt_regs.orig_ax & __X32_SYSCALL_BIT ia64 !ia32 && !x32 child->thread.status is corretly set up in set_personality_*(), but the syscall number in child->pt_regs.orig_ax is left unmodified. Therefore the parent/child combinations work or fail in the following way: Parent Child Child->thread_status child->pt_regs.orig_ax in_compat() Works ia64 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false Y ia64 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 0 true Y ia64 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false N ia32 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false Y ia32 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 0 true Y ia32 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false N x32 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 1 true N x32 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 1 true Y x32 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 1 true Y Make set_personality_*() store the syscall number incl. __X32_SYSCALL_BIT which corresponds to the newly started ELF executable in the childs pt_regs, i.e. pretend that the exec was invoked from a task with the same executable format. So both thread.status and pt_regs.orig_ax correspond to the new ELF format and in_compat_syscall() returns the correct result. [ tglx: Rewrote changelog ] Fixes: commit 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()") Reported-by: Adam Borowski <kilobyte@angband.pl> Suggested-by: H. Peter Anvin <hpa@zytor.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: 0x7f454c46@gmail.com Cc: linux-mm@kvack.org Cc: Andrei Vagin <avagin@gmail.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Borislav Petkov <bp@suse.de> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/20170331111137.28170-1-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-31x86/pci-calgary: Use setup_timer() instead of open coding it.Geliang Tang
Use setup_timer() instead of init_timer() to simplify the code. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Cc: iommu@lists.linux-foundation.org Cc: Jon Mason <jdmason@kudzu.us> Cc: Muli Ben-Yehuda <mulix@mulix.org> Link: http://lkml.kernel.org/r/e4f1888b9e4a87f6a6345f86ed23071483763b22.1490340972.git.geliangtang@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-31x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRsYazen Ghannam
MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name. However, MCA bank 3 is defined on Fam17h systems and can be accessed using legacy MSRs. Without a name we get a stack trace on Fam17h systems when trying to register sysfs files for bank 3 on kernels that don't recognize Scalable MCA. Call MCA bank 3 "decode_unit" since this is what it represents on Fam17h. This will allow kernels without SMCA support to see this bank on Fam17h+ and prevent the stack trace. This will not affect older systems since this bank is reserved on them, i.e. it'll be ignored. Tested on AMD Fam15h and Fam17h systems. WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal kobject: (ffff88085bb256c0): attempted to be registered with empty name! ... Call Trace: kobject_add_internal kobject_add kobject_create_and_add threshold_create_device threshold_init_device Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-30x86/build: Mostly disable '-maccumulate-outgoing-args'Josh Poimboeuf
The GCC '-maccumulate-outgoing-args' flag is enabled for most configs, mostly because of issues which are no longer relevant. For most configs, and with most recent versions of GCC, it's no longer needed. Clarify which cases need it, and only enable it for those cases. Also produce a compile-time error for the ftrace graph + mcount + '-Os' case, which will otherwise cause runtime failures. The main benefit of '-maccumulate-outgoing-args' is that it prevents an ugly prologue for functions which have aligned stacks. But removing the option also has some benefits: more readable argument saves, smaller text size, and (presumably) slightly improved performance. Here are the object size savings for 32-bit and 64-bit defconfig kernels: text data bss dec hex filename 10006710 3543328 1773568 15323606 e9d1d6 vmlinux.x86-32.before 9706358 3547424 1773568 15027350 e54c96 vmlinux.x86-32.after text data bss dec hex filename 10652105 4537576 843776 16033457 f4a6b1 vmlinux.x86-64.before 10639629 4537576 843776 16020981 f475f5 vmlinux.x86-64.after That comes out to a 3% text size improvement on x86-32 and a 0.1% text size improvement on x86-64. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170316193133.zrj6gug53766m6nn@treble Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-30Merge branch 'x86/cpu' into x86/mm, before applying dependent patchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28ftrace/x86: Do no run CPU sync when there is only one CPU onlineSteven Rostedt (VMware)
Moving enabling of function tracing to early boot, even before scheduling is enabled, means that it is not safe to enable interrupts. When function tracing was enabled at boot up, it use to happen after scheduling and the other CPUs were brought up. That required running a sync across all CPUs when modifying the function hook locations in the code. To do the synchronization, interrupts had to be enabled. Now function tracing can be started before the other CPUs are brought up, and enabling interrupts in that case is dangerous. As only tho boot CPU is active, there is no reason to run the synchronization. If the online CPU count is one, do not bother doing the synchronization. This removes the need to enable interrupts. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-03-28x86/mce: Do not register notifiers with invalid prioBorislav Petkov
This is just a defensive precaution: do not register notifiers with a priority which would disrupt the error handling in the notifiers with prio higher than MCE_PRIO_EDAC. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-7-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28x86/mce: Factor out and deprecate the /dev/mcelog driverTony Luck
Move all code relating to /dev/mcelog to a separate source file. /dev/mcelog driver can now operate from the machine check notifier with lowest prio. Signed-off-by: Tony Luck <tony.luck@intel.com> [ Move the mce_helper and trigger functionality behind CONFIG_X86_MCELOG_LEGACY. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-6-bp@alien8.de [ Renamed CONFIG_X86_MCELOG to CONFIG_X86_MCELOG_LEGACY. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28RAS: Add a Corrected Errors CollectorBorislav Petkov
Introduce a simple data structure for collecting correctable errors along with accessors. More detailed description in the code itself. The error decoding is done with the decoding chain now and mce_first_notifier() gets to see the error first and the CEC decides whether to log it and then the rest of the chain doesn't hear about it - basically the main reason for the CE collector - or to continue running the notifiers. When the CEC hits the action threshold, it will try to soft-offine the page containing the ECC and then the whole decoding chain gets to see the error. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-5-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28x86/mce: Rename mce_log to mce_log_bufferBorislav Petkov
It is confusing when staring at "struct mce_log mcelog" and then there's also a function called mce_log(). So call the buffer what it is. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-4-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28x86/mce: Rename mce_log()'s argumentBorislav Petkov
We call it everywhere "struct mce *m". Adjust that here too to avoid confusion. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20170327093304.10683-3-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28Merge branch 'ras/urgent' into ras/core, to pick up fixIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-28x86/mce: Don't print MCEs when mcelog is activeAndi Kleen
Since: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") all MCEs are printed even when mcelog is running. Fix the regression to not print to dmesg when mcelog is running as it is a consumer too. Signed-off-by: Andi Kleen <ak@linux.intel.com> [ Massage commit message. ] Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-edac <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org # 4.10.. Fixes: cd9c57cad3fe ("x86/MCE: Dump MCE to dmesg if no consumers") Link: http://lkml.kernel.org/r/20170327093304.10683-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27x86/debug: Implement __WARN() using UD0Peter Zijlstra
By using "UD0" for WARN()s we remove the function call and its possible __FILE__ and __LINE__ immediate arguments from the instruction stream. Total image size will not change much, what we win in the instruction stream we'll lose because of the __bug_table entries. Still, saves on I$ footprint and the total image size does go down a bit. text data filename 10702123 4530992 defconfig-build/vmlinux.orig 10682460 4530992 defconfig-build/vmlinux.patched (UML didn't seem to use GENERIC_BUG at all, so remove it) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard.weinberger@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27x86: Convert the rest of the code to support p4d_tKirill A. Shutemov
This patch converts x86 to use proper folding of a new (fifth) page table level with <asm-generic/pgtable-nop4d.h>. That's a bit of a kitchen sink patch, but I don't see how to split it further without hurting bisectability. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170317185515.8636-7-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-27x86/kexec: Add 5-level paging supportKirill A. Shutemov
Handle additional page table level in the kexec code. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170317185515.8636-2-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-24x86/ftrace: Use Makefile logic instead of #ifdef for compiling ftrace_*.oSteven Rostedt (VMware)
Currently ftrace_32.S and ftrace_64.S are compiled even when CONFIG_FUNCTION_TRACER is not set. This means there's an unnecessary #ifdef to protect the code. Instead of using preprocessor directives, only compile those files when FUNCTION_TRACER is defined. Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170316210043.peycxdxktwwn6cid@treble Link: http://lkml.kernel.org/r/20170323143446.217684991@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Add -mfentry support to x86_32 with DYNAMIC_FTRACE setSteven Rostedt (VMware)
x86_64 has had fentry support for some time. I did not add support to x86_32 as I was unsure if it will be used much in the future. It is still very much used, and there's issues with function graph tracing with gcc playing around with the mcount frames, causing function graph to panic. The fentry code does not have this issue, and is able to cope as there is no frame to mess up. Note, this only adds support for fentry when DYNAMIC_FTRACE is set. There's really no reason to not have that set, because the performance of the machine drops significantly when it's not enabled. Keep !DYNAMIC_FTRACE around to test it off, as there's still some archs that have FTRACE but not DYNAMIC_FTRACE. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170323143446.052202377@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Clean up ftrace_regs_callerSteven Rostedt (VMware)
When ftrace_regs_caller was created, it was designed to preserve flags as much as possible as it needed to act just like a breakpoint triggered on the same location. But the design is over complicated as it treated all operations as modifying flags. But push, mov and lea do not modify flags. This means the code can become more simplified by allowing flags to be stored further down. Making ftrace_regs_caller simpler will also be useful in implementing fentry logic. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20170316135328.36123c3e@gandalf.local.home Link: http://lkml.kernel.org/r/20170323143445.917292592@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Add stack frame pointer to ftrace_callerSteven Rostedt (VMware)
The function hook ftrace_caller does not create its own stack frame, and this causes the ftrace stack trace to miss the first function when doing stack traces. # echo schedule:stacktrace > /sys/kernel/tracing/set_ftrace_filter Before: <idle>-0 [002] .N.. 29.865807: <stack trace> => cpu_startup_entry => start_secondary => startup_32_smp <...>-7 [001] .... 29.866509: <stack trace> => kthread => ret_from_fork <...>-1 [000] .... 29.865377: <stack trace> => poll_schedule_timeout => do_select => core_sys_select => SyS_select => do_fast_syscall_32 => entry_SYSENTER_32 After: <idle>-0 [002] .N.. 31.234853: <stack trace> => do_idle => cpu_startup_entry => start_secondary => startup_32_smp <...>-7 [003] .... 31.235140: <stack trace> => rcu_gp_kthread => kthread => ret_from_fork <...>-1819 [000] .... 31.264172: <stack trace> => schedule_hrtimeout_range => poll_schedule_timeout => do_sys_poll => SyS_ppoll => do_fast_syscall_32 => entry_SYSENTER_32 Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170323143445.771707773@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Move the ftrace specific code out of entry_32.SSteven Rostedt (VMware)
The function tracing hook code for ftrace is not an entry point from userspace and does not belong in the entry_*.S files. It has already been moved out of entry_64.S. Move it out of entry_32.S into its own ftrace_32.S file. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170323143445.645218946@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Rename mcount_64.S to ftrace_64.SSteven Rostedt (VMware)
With the advent of -mfentry that uses the new "fentry" hook over mcount, the mcount name is obsolete. Having the code file that ftrace hooks into called "mcount*.S" is rather misleading. Rename it to ftrace_64.S and remove the file name reference. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170323143445.490601451@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-23Merge branch 'x86/process' into x86/mm, to create new base for further patchesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-23x86/xen/gdt: Use X86_FEATURE_XENPV instead of globals for the GDT fixupAndy Lutomirski
Xen imposes special requirements on the GDT. Rather than using a global variable for the pgprot, just use an explicit special case for Xen -- this makes it clearer what's going on. It also debloats 64-bit kernels very slightly. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/e9ea96abbfd6a8c87753849171bb5987ecfeb523.1490218061.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-23x86/boot/32: Defer resyncing initial_page_table until per-cpu is set upAndy Lutomirski
The x86 smpboot trampoline expects initial_page_table to have the GDT mapped. If the GDT ends up in a virtually mapped per-cpu page, then it won't be in the page tables at all until perc-pu areas are set up. The result will be a triple fault the first time that the CPU attempts to access the GDT after LGDT loads the perc-pu GDT. This appears to be an old bug, but somehow the GDT fixmap rework is triggering it. This seems to have something to do with the memory layout. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/a553264a5972c6a86f9b5caac237470a0c74a720.1490218061.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>