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2017-11-14x86/umip: Print a line in the boot log that UMIP has been enabledRicardo Neri
Indicate that this feature has been enabled. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi V. Shankar <ravi.v.shankar@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: ricardo.neri@intel.com Link: http://lkml.kernel.org/r/1510640985-18412-3-git-send-email-ricardo.neri-calderon@linux.intel.com [ Changelog tweaks. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-13Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "Three smaller changes: - clang fix - boot message beautification - unnecessary header inclusion removal" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Disable Clang warnings about GNU extensions x86/boot: Remove unnecessary #include <generated/utsrelease.h> x86/boot: Spell out "boot CPU" for BP
2017-11-08x86/umip: Enable User-Mode Instruction Prevention at runtimeRicardo Neri
User-Mode Instruction Prevention (UMIP) is enabled by setting/clearing a bit in %cr4. It makes sense to enable UMIP at some point while booting, before user spaces come up. Like SMAP and SMEP, is not critical to have it enabled very early during boot. This is because UMIP is relevant only when there is a user space to be protected from. Given these similarities, UMIP can be enabled along with SMAP and SMEP. At the moment, UMIP is disabled by default at build time. It can be enabled at build time by selecting CONFIG_X86_INTEL_UMIP. If enabled at build time, it can be disabled at run time by adding clearcpuid=514 to the kernel parameters. Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> 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: Chen Yucong <slaoub@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang Rui <ray.huang@amd.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi V. Shankar <ravi.v.shankar@intel.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: ricardo.neri@intel.com Link: http://lkml.kernel.org/r/1509935277-22138-10-git-send-email-ricardo.neri-calderon@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Stop initializing TSS.sp0 at bootAndy Lutomirski
In my quest to get rid of thread_struct::sp0, I want to clean up or remove all of its readers. Two of them are in cpu_init() (32-bit and 64-bit), and they aren't needed. This is because we never enter userspace at all on the threads that CPUs are initialized in. Poison the initial TSS.sp0 and stop initializing it on CPU init. The comment text mostly comes from Dave Hansen. Thanks! Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ee4a00540ad28c6cff475fbcc7769a4460acc861.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02x86/entry/64: Pass SP0 directly to load_sp0()Andy Lutomirski
load_sp0() had an odd signature: void load_sp0(struct tss_struct *tss, struct thread_struct *thread); Simplify it to: void load_sp0(unsigned long sp0); Also simplify a few get_cpu()/put_cpu() sequences to preempt_disable()/preempt_enable(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2655d8b42ed940aa384fe18ee1129bbbcf730a08.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-17x86/fpu: Parse clearcpuid= as early XSAVE argumentAndi Kleen
With a followon patch we want to make clearcpuid affect the XSAVE configuration. But xsave is currently initialized before arguments are parsed. Move the clearcpuid= parsing into the special early xsave argument parsing code. Since clearcpuid= contains a = we need to keep the old __setup around as a dummy, otherwise it would end up as a environment variable in init's environment. Signed-off-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20171013215645.23166-4-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-03x86/boot: Spell out "boot CPU" for BPJean Delvare
It's not obvious to everybody that BP stands for boot processor. At least it was not for me. And BP is also a CPU register on x86, so it is ambiguous. Spell out "boot CPU" everywhere instead. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Alok Kataria <akataria@vmware.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-17x86/mm/32: Move setup_clear_cpu_cap(X86_FEATURE_PCID) earlierAndy Lutomirski
Otherwise we might have the PCID feature bit set during cpu_init(). This is just for robustness. I haven't seen any actual bugs here. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: cba4671af755 ("x86/mm: Disable PCID on 32-bit kernels") Link: http://lkml.kernel.org/r/b16dae9d6b0db5d9801ddbebbfd83384097c61f3.1505663533.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-13x86/mm/64: Initialize CR4.PCIDE earlyAndy Lutomirski
cpu_init() is weird: it's called rather late (after early identification and after most MMU state is initialized) on the boot CPU but is called extremely early (before identification) on secondary CPUs. It's called just late enough on the boot CPU that its CR4 value isn't propagated to mmu_cr4_features. Even if we put CR4.PCIDE into mmu_cr4_features, we'd hit two problems. First, we'd crash in the trampoline code. That's fixable, and I tried that. It turns out that mmu_cr4_features is totally ignored by secondary_start_64(), though, so even with the trampoline code fixed, it wouldn't help. This means that we don't currently have CR4.PCIDE reliably initialized before we start playing with cpu_tlbstate. This is very fragile and tends to cause boot failures if I make even small changes to the TLB handling code. Make it more robust: initialize CR4.PCIDE earlier on the boot CPU and propagate it to secondary CPUs in start_secondary(). ( Yes, this is ugly. I think we should have improved mmu_cr4_features to actually control CR4 during secondary bootup, but that would be fairly intrusive at this stage. ) Signed-off-by: Andy Lutomirski <luto@kernel.org> Reported-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Borislav Petkov <bpetkov@suse.de> 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 Fixes: 660da7c9228f ("x86/mm: Enable CR4.PCIDE on supported systems") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-06x86/mm: Document how CR4.PCIDE restore worksAndy Lutomirski
While debugging a problem, I thought that using cr4_set_bits_and_update_boot() to restore CR4.PCIDE would be helpful. It turns out to be counterproductive. Add a comment documenting how this works. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06x86/mm: Reinitialize TLB state on hotplug and resumeAndy Lutomirski
When Linux brings a CPU down and back up, it switches to init_mm and then loads swapper_pg_dir into CR3. With PCID enabled, this has the side effect of masking off the ASID bits in CR3. This can result in some confusion in the TLB handling code. If we bring a CPU down and back up with any ASID other than 0, we end up with the wrong ASID active on the CPU after resume. This could cause our internal state to become corrupt, although major corruption is unlikely because init_mm doesn't have any user pages. More obviously, if CONFIG_DEBUG_VM=y, we'll trip over an assertion in the next context switch. The result of *that* is a failure to resume from suspend with probability 1 - 1/6^(cpus-1). Fix it by reinitializing cpu_tlbstate on resume and CPU bringup. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Jiri Kosina <jikos@kernel.org> Fixes: 10af6235e0d3 ("x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-04Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Thomas Gleixner: "This update provides: - Cleanup of the IDT management including the removal of the extra tracing IDT. A first step to cleanup the vector management code. - The removal of the paravirt op adjust_exception_frame. This is a XEN specific issue, but merged through this branch to avoid nasty merge collisions - Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has disabled the TSC DEADLINE timer in CPUID. - Adjust a debug message in the ioapic code to print out the information correctly" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits) x86/idt: Fix the X86_TRAP_BP gate x86/xen: Get rid of paravirt op adjust_exception_frame x86/eisa: Add missing include x86/idt: Remove superfluous ALIGNment x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature x86/idt: Remove the tracing IDT leftovers x86/idt: Hide set_intr_gate() x86/idt: Simplify alloc_intr_gate() x86/idt: Deinline setup functions x86/idt: Remove unused functions/inlines x86/idt: Move interrupt gate initialization to IDT code x86/idt: Move APIC gate initialization to tables x86/idt: Move regular trap init to tables x86/idt: Move IST stack based traps to table init x86/idt: Move debug stack init to table based x86/idt: Switch early trap init to IDT tables x86/idt: Prepare for table based init x86/idt: Move early IDT setup out of 32-bit asm x86/idt: Move early IDT handler setup to IDT code x86/idt: Consolidate IDT invalidation ...
2017-08-29x86/idt: Create file for IDT related codeThomas Gleixner
IDT related code lives scattered around in various places. Create a new source file in arch/x86/kernel/idt.c to hold it. Move the idt_tables and descriptors to it for a start. Follow up patches will gradually move more code over. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064958.367081121@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-05x86/mm: Enable CR4.PCIDE on supported systemsAndy Lutomirski
We can use PCID if the CPU has PCID and PGE and we're not on Xen. By itself, this has no effect. A followup patch will start using PCID. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/6327ecd907b32f79d5aa0d466f04503bbec5df88.1498751203.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-05x86/mm: Add the 'nopcid' boot option to turn off PCIDAndy Lutomirski
The parameter is only present on x86_64 systems to save a few bytes, as PCID is always disabled on x86_32. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Nadav Amit <nadav.amit@gmail.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/8bbb2e65bcd249a5f18bfb8128b4689f08ac2b60.1498751203.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-02x86/cpu: remove hypervisor specific set_cpu_featuresJuergen Gross
There is no user of x86_hyper->set_cpu_features() any more. Remove it. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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/gdt: Fix setup_fixmap_gdt() to use the correct PAAndy Lutomirski
__pa() cannot be used on percpu pointers because they may be virtually mapped. Use per_cpu_ptr_to_phys() instead. This fixes a boot crash on a some 32-bit configurations. I assume this is related to which allocation strategy is chosen by the percpu core. 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> Fixes: 69218e47994d x86: ("Remap GDT tables in the fixmap section") Link: http://lkml.kernel.org/r/22e0069c29fba31998f193201e359eebfdac4960.1490218061.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16x86: Make the GDT remapping read-only on 64-bitThomas Garnier
This patch makes the GDT remapped pages read-only, to prevent accidental (or intentional) corruption of this key data structure. This change is done only on 64-bit, because 32-bit needs it to be writable for TSS switches. The native_load_tr_desc function was adapted to correctly handle a read-only GDT. The LTR instruction always writes to the GDT TSS entry. This generates a page fault if the GDT is read-only. This change checks if the current GDT is a remap and swap GDTs as needed. This function was tested by booting multiple machines and checking hibernation works properly. KVM SVM and VMX were adapted to use the writeable GDT. On VMX, the per-cpu variable was removed for functions to fetch the original GDT. Instead of reloading the previous GDT, VMX will reload the fixmap GDT as expected. For testing, VMs were started and restored on multiple configurations. Signed-off-by: Thomas Garnier <thgarnie@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@suse.de> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Joerg Roedel <joro@8bytes.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Luis R . Rodriguez <mcgrof@kernel.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rafael J . Wysocki <rjw@rjwysocki.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: kasan-dev@googlegroups.com Cc: kernel-hardening@lists.openwall.com Cc: kvm@vger.kernel.org Cc: lguest@lists.ozlabs.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-pm@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: zijun_hu <zijun_hu@htc.com> Link: http://lkml.kernel.org/r/20170314170508.100882-3-thgarnie@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16x86: Remap GDT tables in the fixmap sectionThomas Garnier
Each processor holds a GDT in its per-cpu structure. The sgdt instruction gives the base address of the current GDT. This address can be used to bypass KASLR memory randomization. With another bug, an attacker could target other per-cpu structures or deduce the base of the main memory section (PAGE_OFFSET). This patch relocates the GDT table for each processor inside the fixmap section. The space is reserved based on number of supported processors. For consistency, the remapping is done by default on 32 and 64-bit. Each processor switches to its remapped GDT at the end of initialization. For hibernation, the main processor returns with the original GDT and switches back to the remapping at completion. This patch was tested on both architectures. Hibernation and KVM were both tested specially for their usage of the GDT. Thanks to Boris Ostrovsky <boris.ostrovsky@oracle.com> for testing and recommending changes for Xen support. Signed-off-by: Thomas Garnier <thgarnie@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@suse.de> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Joerg Roedel <joro@8bytes.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@chromium.org> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Luis R . Rodriguez <mcgrof@kernel.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Michal Hocko <mhocko@suse.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rafael J . Wysocki <rjw@rjwysocki.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: kasan-dev@googlegroups.com Cc: kernel-hardening@lists.openwall.com Cc: kvm@vger.kernel.org Cc: lguest@lists.ozlabs.org Cc: linux-doc@vger.kernel.org Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-pm@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: zijun_hu <zijun_hu@htc.com> Link: http://lkml.kernel.org/r/20170314170508.100882-2-thgarnie@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-07Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "A fix for KVM's scheduler clock which (erroneously) was always marked unstable, a fix for RT/DL load balancing, plus latency fixes" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface sched/core: Fix pick_next_task() for RT,DL sched/fair: Make select_idle_cpu() more aggressive
2017-03-03sched/headers: Move task->mm handling methods to <linux/sched/mm.h>Ingo Molnar
Move the following task->mm helper APIs into a new header file, <linux/sched/mm.h>, to further reduce the size and complexity of <linux/sched.h>. Here are how the APIs are used in various kernel files: # mm_alloc(): arch/arm/mach-rpc/ecard.c fs/exec.c include/linux/sched/mm.h kernel/fork.c # __mmdrop(): arch/arc/include/asm/mmu_context.h include/linux/sched/mm.h kernel/fork.c # mmdrop(): arch/arm/mach-rpc/ecard.c arch/m68k/sun3/mmu_emu.c arch/x86/mm/tlb.c drivers/gpu/drm/amd/amdkfd/kfd_process.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/hw/hfi1/file_ops.c drivers/vfio/vfio_iommu_spapr_tce.c fs/exec.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/mmu_notifier.h include/linux/sched/mm.h kernel/fork.c kernel/futex.c kernel/sched/core.c mm/khugepaged.c mm/ksm.c mm/mmu_context.c mm/mmu_notifier.c mm/oom_kill.c virt/kvm/kvm_main.c # mmdrop_async_fn(): include/linux/sched/mm.h # mmdrop_async(): include/linux/sched/mm.h kernel/fork.c # mmget_not_zero(): fs/userfaultfd.c include/linux/sched/mm.h mm/oom_kill.c # mmput(): arch/arc/include/asm/mmu_context.h arch/arc/kernel/troubleshoot.c arch/frv/mm/mmu-context.c arch/powerpc/platforms/cell/spufs/context.c arch/sparc/include/asm/mmu_context_32.h drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/gpu/drm/i915/i915_gem_userptr.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/core/uverbs_main.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/exec.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c fs/proc/task_nommu.c fs/userfaultfd.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/events/uprobes.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/oom_kill.c mm/process_vm_access.c mm/rmap.c mm/swapfile.c mm/util.c virt/kvm/async_pf.c # mmput_async(): include/linux/sched/mm.h kernel/fork.c mm/oom_kill.c # get_task_mm(): arch/arc/kernel/troubleshoot.c arch/powerpc/platforms/cell/spufs/context.c drivers/android/binder.c drivers/gpu/drm/etnaviv/etnaviv_gem.c drivers/infiniband/core/umem.c drivers/infiniband/core/umem_odp.c drivers/infiniband/hw/mlx4/main.c drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/usnic/usnic_uiom.c drivers/iommu/amd_iommu_v2.c drivers/iommu/intel-svm.c drivers/lguest/lguest_user.c drivers/misc/cxl/fault.c drivers/misc/mic/scif/scif_rma.c drivers/oprofile/buffer_sync.c drivers/vfio/vfio_iommu_type1.c drivers/vhost/vhost.c drivers/xen/gntdev.c fs/proc/array.c fs/proc/base.c fs/proc/task_mmu.c include/linux/sched/mm.h kernel/cpuset.c kernel/events/core.c kernel/exit.c kernel/fork.c kernel/ptrace.c kernel/sys.c kernel/trace/trace_output.c kernel/tsacct.c mm/memcontrol.c mm/memory.c mm/mempolicy.c mm/migrate.c mm/mmu_notifier.c mm/nommu.c mm/util.c # mm_access(): fs/proc/base.c include/linux/sched/mm.h kernel/fork.c mm/process_vm_access.c # mm_release(): arch/arc/include/asm/mmu_context.h fs/exec.c include/linux/sched/mm.h include/uapi/linux/sched.h kernel/exit.c kernel/fork.c Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> 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>
2017-03-02sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interfacePeter Zijlstra
Wanpeng Li reported that since the following commit: acb04058de49 ("sched/clock: Fix hotplug crash") ... KVM always runs with unstable sched-clock even though KVM's kvm_clock _is_ stable. The problem is that we've tied clear_sched_clock_stable() to the TSC state, and overlooked that sched_clock() is a paravirt function. Solve this by doing two things: - tie the sched_clock() stable state more clearly to the TSC stable state for the normal (!paravirt) case. - only call clear_sched_clock_stable() when we mark TSC unstable when we use native_sched_clock(). The first means we can actually run with stable sched_clock in more situations then before, which is good. And since commit: 12907fbb1a69 ("sched/clock, clocksource: Add optional cs::mark_unstable() method") ... this should be reliable. Since any detection of TSC fail now results in marking the TSC unstable. Reported-by: Wanpeng Li <kernellwp@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Fixes: acb04058de49 ("sched/clock: Fix hotplug crash") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare to move 'init_task' and 'init_thread_union' from ↵Ingo Molnar
<linux/sched.h> to <linux/sched/task.h> Update all usage sites first. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> 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>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> 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>
2017-02-27mm: add new mmgrab() helperVegard Nossum
Apart from adding the helper function itself, the rest of the kernel is converted mechanically using: git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)->mm_count);/mmgrab\(\1\);/' git grep -l 'atomic_inc.*mm_count' | xargs sed -i 's/atomic_inc(&\(.*\)\.mm_count);/mmgrab\(\&\1\);/' This is needed for a later patch that hooks into the helper, but might be a worthwhile cleanup on its own. (Michal Hocko provided most of the kerneldoc comment.) Link: http://lkml.kernel.org/r/20161218123229.22952-1-vegard.nossum@oracle.com Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-20Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fpu updates from Ingo Molnar: "The main changes relate to fixes between (lack of) CPUID and FPU detection that should only affect old or weird CPUs, by Andy Lutomirski" * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu: Fix the "Giving up, no FPU found" test x86/fpu: Fix CPUID-less FPU detection x86/fpu: Fix "x86/fpu: Legacy x87 FPU detected" message x86/cpu: Re-apply forced caps every time CPU caps are re-read x86/cpu: Factor out application of forced CPU caps x86/cpu: Add X86_FEATURE_CPUID x86/fpu/xstate: Move XSAVES state init to a function
2017-02-20Merge branch 'x86-cpufeature-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpufeature updates from Ingo Molnar: "The main changes in this cycle were related to enable ring-3 MONITOR/MWAIT instructions support on supported CPUs, by Grzegorz Andrejczuk and Piotr Luc" * 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpufeature: Move RING3MWAIT feature to avoid conflicts x86/cpufeature: Enable RING3MWAIT for Knights Mill x86/cpufeature: Enable RING3MWAIT for Knights Landing x86/cpufeature: Add RING3MWAIT to CPU features x86/elf: Add HWCAP2 to expose ring 3 MONITOR/MWAIT x86/msr: Add MSR_MISC_FEATURE_ENABLES and RING3MWAIT bit x86/cpufeature: Add AVX512_VPOPCNTDQ feature
2017-02-20Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this (fairly busy) cycle were: - There was a class of scheduler bugs related to forgetting to update the rq-clock timestamp which can cause weird and hard to debug problems, so there's a new debug facility for this: which uncovered a whole lot of bugs which convinced us that we want to keep the debug facility. (Peter Zijlstra, Matt Fleming) - Various cputime related updates: eliminate cputime and use u64 nanoseconds directly, simplify and improve the arch interfaces, implement delayed accounting more widely, etc. - (Frederic Weisbecker) - Move code around for better structure plus cleanups (Ingo Molnar) - Move IO schedule accounting deeper into the scheduler plus related changes to improve the situation (Tejun Heo) - ... plus a round of sched/rt and sched/deadline fixes, plus other fixes, updats and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (85 commits) sched/core: Remove unlikely() annotation from sched_move_task() sched/autogroup: Rename auto_group.[ch] to autogroup.[ch] sched/topology: Split out scheduler topology code from core.c into topology.c sched/core: Remove unnecessary #include headers sched/rq_clock: Consolidate the ordering of the rq_clock methods delayacct: Include <uapi/linux/taskstats.h> sched/core: Clean up comments sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds sched/clock: Add dummy clear_sched_clock_stable() stub function sched/cputime: Remove generic asm headers sched/cputime: Remove unused nsec_to_cputime() s390, sched/cputime: Remove unused cputime definitions powerpc, sched/cputime: Remove unused cputime definitions s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs ia64, sched/cputime: Remove unused cputime definitions ia64: Convert vtime to use nsec units directly ia64, sched/cputime: Move the nsecs based cputime headers to the last arch using it sched/cputime: Remove jiffies based cputime sched/cputime, vtime: Return nsecs instead of cputime_t to account sched/cputime: Complete nsec conversion of tick based accounting ...
2017-02-05x86/CPU/AMD: Bring back Compute Unit IDBorislav Petkov
Commit: a33d331761bc ("x86/CPU/AMD: Fix Bulldozer topology") restored the initial approach we had with the Fam15h topology of enumerating CU (Compute Unit) threads as cores. And this is still correct - they're beefier than HT threads but still have some shared functionality. Our current approach has a problem with the Mad Max Steam game, for example. Yves Dionne reported a certain "choppiness" while playing on v4.9.5. That problem stems most likely from the fact that the CU threads share resources within one CU and when we schedule to a thread of a different compute unit, this incurs latency due to migrating the working set to a different CU through the caches. When the thread siblings mask mirrors that aspect of the CUs and threads, the scheduler pays attention to it and tries to schedule within one CU first. Which takes care of the latency, of course. Reported-by: Yves Dionne <yves.dionne@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: <stable@vger.kernel.org> # 4.9 Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yazen Ghannam <yazen.ghannam@amd.com> Link: http://lkml.kernel.org/r/20170205105022.8705-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-04x86/elf: Add HWCAP2 to expose ring 3 MONITOR/MWAITGrzegorz Andrejczuk
Introduce ELF_HWCAP2 variable for x86 and reserve its bit 0 to expose the ring 3 MONITOR/MWAIT. HWCAP variables contain bitmasks which can be used by userspace applications to detect which instruction sets are supported by CPU. On x86 architecture information about CPU capabilities can be checked via CPUID instructions, unfortunately presence of ring 3 MONITOR/MWAIT feature cannot be checked this way. ELF_HWCAP cannot be used as well, because on x86 it is set to CPUID[1].EDX which means that all bits are reserved there. HWCAP2 approach was chosen because it reuses existing solution present in other architectures, so only minor modifications are required to the kernel and userspace applications. When ELF_HWCAP2 is defined kernel maps it to AT_HWCAP2 during the start of the application. This way the ring 3 MONITOR/MWAIT feature can be detected using getauxval() API in a simple and fast manner. ELF_HWCAP2 type is u32 to be consistent with x86 ELF_HWCAP type. Signed-off-by: Grzegorz Andrejczuk <grzegorz.andrejczuk@intel.com> Cc: Piotr.Luc@intel.com Cc: dave.hansen@linux.intel.com Link: http://lkml.kernel.org/r/1484918557-15481-3-git-send-email-grzegorz.andrejczuk@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-02-01Merge branch 'linus' into sched/core, to pick up fixes and refresh the branchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25x86/cpu: Re-apply forced caps every time CPU caps are re-readAndy Lutomirski
Calling get_cpu_cap() will reset a bunch of CPU features. This will cause the system to lose track of force-set and force-cleared features in the words that are reset until the end of CPU initialization. This can cause X86_FEATURE_FPU, for example, to change back and forth during boot and potentially confuse CPU setup. To minimize the chance of confusion, re-apply forced caps every time get_cpu_cap() is called. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Whitehead <tedheadster@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/c817eb373d2c67c2c81413a70fc9b845fa34a37e.1484705016.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25x86/cpu: Factor out application of forced CPU capsAndy Lutomirski
There are multiple call sites that apply forced CPU caps. Factor them into a helper. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Whitehead <tedheadster@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/623ff7555488122143e4417de09b18be2085ad06.1484705016.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25x86/cpu: Add X86_FEATURE_CPUIDBorislav Petkov
Add a synthetic CPUID flag denoting whether the CPU sports the CPUID instruction or not. This will come useful later when accomodating CPUID-less CPUs. Signed-off-by: Borislav Petkov <bp@suse.de> [ Slightly prettified. ] Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Whitehead <tedheadster@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Link: http://lkml.kernel.org/r/dcb355adae3ab812c79397056a61c212f1a0c7cc.1484705016.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-20sched/clock: Fix hotplug crashPeter Zijlstra
Mike reported that he could trigger the WARN_ON_ONCE() in set_sched_clock_stable() using hotplug. This exposed a fundamental problem with the interface, we should never mark the TSC stable if we ever find it to be unstable. Therefore set_sched_clock_stable() is a broken interface. The reason it existed is that not having it is a pain, it means all relevant architecture code needs to call clear_sched_clock_stable() where appropriate. Of the three architectures that select HAVE_UNSTABLE_SCHED_CLOCK ia64 and parisc are trivial in that they never called set_sched_clock_stable(), so add an unconditional call to clear_sched_clock_stable() to them. For x86 the story is a lot more involved, and what this patch tries to do is ensure we preserve the status quo. So even is Cyrix or Transmeta have usable TSC they never called set_sched_clock_stable() so they now get an explicit mark unstable. Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 9881b024b7d7 ("sched/clock: Delay switching sched_clock to stable") Link: http://lkml.kernel.org/r/20170119133633.GB6536@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-05x86/cpu: Fix bootup crashes by sanitizing the argument of the 'clearcpuid=' ↵Lukasz Odzioba
command-line option A negative number can be specified in the cmdline which will be used as setup_clear_cpu_cap() argument. With that we can clear/set some bit in memory predceeding boot_cpu_data/cpu_caps_cleared which may cause kernel to misbehave. This patch adds lower bound check to setup_disablecpuid(). Boris Petkov reproduced a crash: [ 1.234575] BUG: unable to handle kernel paging request at ffffffff858bd540 [ 1.236535] IP: memcpy_erms+0x6/0x10 Signed-off-by: Lukasz Odzioba <lukasz.odzioba@intel.com> Acked-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: andi.kleen@intel.com Cc: bp@alien8.de Cc: dave.hansen@linux.intel.com Cc: luto@kernel.org Cc: slaoub@gmail.com Fixes: ac72e7888a61 ("x86: add generic clearcpuid=... option") Link: http://lkml.kernel.org/r/1482933340-11857-1-git-send-email-lukasz.odzioba@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-19x86/cpu: Probe CPUID leaf 6 even when cpuid_level == 6Andy Lutomirski
A typo (or mis-merge?) resulted in leaf 6 only being probed if cpuid_level >= 7. Fixes: 2ccd71f1b278 ("x86/cpufeature: Move some of the scattered feature bits to x86_capability") Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Link: http://lkml.kernel.org/r/6ea30c0e9daec21e488b54761881a6dfcf3e04d0.1481825597.git.luto@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-13x86/smpboot: Make logical package management more robustThomas Gleixner
The logical package management has several issues: - The APIC ids provided by ACPI are not required to be the same as the initial APIC id which can be retrieved by CPUID. The APIC ids provided by ACPI are those which are written by the BIOS into the APIC. The initial id is set by hardware and can not be changed. The hardware provided ids contain the real hardware package information. Especially AMD sets the effective APIC id different from the hardware id as they need to reserve space for the IOAPIC ids starting at id 0. As a consequence those machines trigger the currently active firmware bug printouts in dmesg, These are obviously wrong. - Virtual machines have their own interesting of enumerating APICs and packages which are not reliably covered by the current implementation. The sizing of the mapping array has been tweaked to be generously large to handle systems which provide a wrong core count when HT is disabled so the whole magic which checks for space in the physical hotplug case is not needed anymore. Simplify the whole machinery and do the mapping when the CPU starts and the CPUID derived physical package information is available. This solves the observed problems on AMD machines and works for the virtualization issues as well. Remove the extra call from XEN cpu bringup code as it is not longer required. Fixes: d49597fd3bc7 ("x86/cpu: Deal with broken firmware (VMWare/XEN)") Reported-and-tested-by: Borislav Petkov <bp@suse.de> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Juergen Gross <jgross@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: M. Vefa Bicakci <m.v.b@runbox.com> Cc: xen-devel <xen-devel@lists.xen.org> Cc: Charles (Chas) Williams <ciwillia@brocade.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Alok Kataria <akataria@vmware.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1612121102260.3429@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-12Merge branch 'x86-microcode-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode update from Ingo Molnar: "The biggest change (by Borislav Petkov) is a thorough rewrite of the Intel microcode loader and its interactions with the core code. The biggest conceptual change is the decoupling of the microcode loading on boot and application processors (which load the microcode in different scenarios), so that both parse the input patches with as few assumptions as possible - this also fixes various kernel address space randomization bugs. (The AP side then goes on and caches the result to improve boot performance.) Since the AMD side already did this, this change also opened up the path towards more unification/simplification of the core microcode loading infrastructure: 10 files changed, 647 insertions(+), 940 deletions(-) which speaks for itself" * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Bump driver version, update copyrights x86/microcode: Rework microcode loading x86/microcode/intel: Remove intel_lib.c x86/microcode/amd: Move private inlines to .c and mark local functions static x86/microcode: Collect CPU info on resume x86/microcode: Issue the debug printk on resume only on success x86/microcode/amd: Hand down the CPU family x86/microcode: Export the microcode cache linked list x86/microcode: Remove one #ifdef clause x86/microcode/intel: Simplify generic_load_microcode() x86/microcode: Move driver authors to CREDITS x86/microcode: Run the AP-loading routine only on the application processors
2016-12-12Merge branch 'x86-idle-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 idle updates from Ingo Molnar: "There were two bigger changes in this development cycle: - remove idle notifiers: 32 files changed, 74 insertions(+), 803 deletions(-) These notifiers were of questionable value and the main usecase, the i7300 driver, was essentially unmaintained and can be removed, plus modern power management concepts don't need the callback - so use this golden opportunity and get rid of this opaque and fragile callback from a latency sensitive code path. (Len Brown, Thomas Gleixner) - improve the AMD Erratum 400 workaround that used high overhead MSR polling in the idle loop (Borisla Petkov, Thomas Gleixner)" * 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Remove empty idle.h header x86/amd: Simplify AMD E400 aware idle routine x86/amd: Check for the C1E bug post ACPI subsystem init x86/bugs: Separate AMD E400 erratum and C1E bug x86/cpufeature: Provide helper to set bugs bits x86/idle: Remove enter_idle(), exit_idle() x86: Remove x86_test_and_clear_bit_percpu() x86/idle: Remove is_idle flag x86/idle: Remove idle_notifier i7300_idle: Remove this driver
2016-12-12Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU updates from Ingo Molnar: "The changes in this development cycle were: - AMD CPU topology enhancements that are cleanups on current CPUs but which enable future Fam17 hardware. (Yazen Ghannam) - unify bugs.c and bugs_64.c (Borislav Petkov) - remove the show_msr= boot option (Borislav Petkov) - simplify a boot message (Borislav Petkov)" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu/AMD: Clean up cpu_llc_id assignment per topology feature x86/cpu: Get rid of the show_msr= boot option x86/cpu: Merge bugs.c and bugs_64.c x86/cpu: Remove the printk format specifier in "CPU0: "
2016-12-09x86/amd: Simplify AMD E400 aware idle routineBorislav Petkov
Reorganize the E400 detection now that we have everything in place: switch the CPUs to broadcast mode after the LAPIC has been initialized and remove the facilities that were used previously on the idle path. Unfortunately static_cpu_has_bug() cannpt be used in the E400 idle routine because alternatives have been applied when the actual detection happens, so the static switching does not take effect and the test will stay false. Use boot_cpu_has_bug() instead which is definitely an improvement over the RDMSR and the cpumask handling. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20161209182912.2726-5-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09x86/cpu: Deal with broken firmware (VMWare/XEN)Thomas Gleixner
Both ACPI and MP specifications require that the APIC id in the respective tables must be the same as the APIC id in CPUID. The kernel retrieves the physical package id from the APIC id during the ACPI/MP table scan and builds the physical to logical package map. The physical package id which is used after a CPU comes up is retrieved from CPUID. So we rely on ACPI/MP tables and CPUID agreeing in that respect. There exist VMware and XEN implementations which violate the spec. As a result the physical to logical package map, which relies on the ACPI/MP tables does not work on those systems, because the CPUID initialized physical package id does not match the firmware id. This causes system crashes and malfunction due to invalid package mappings. The only way to cure this is to sanitize the physical package id after the CPUID enumeration and yell when the APIC ids are different. Fix up the initial APIC id, which is fine as it is only used printout purposes. If the physical package IDs differ yell and use the package information from the ACPI/MP tables so the existing logical package map just works. Chas provided the resulting dmesg output for his affected 4 virtual sockets, 1 core per socket VM: [Firmware Bug]: CPU1: APIC id mismatch. Firmware: 1 CPUID: 2 [Firmware Bug]: CPU1: Using firmware package id 1 instead of 2 .... Reported-and-tested-by: "Charles (Chas) Williams" <ciwillia@brocade.com>, Reported-by: M. Vefa Bicakci <m.v.b@runbox.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Alok Kataria <akataria@vmware.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: #4.6+ <stable@vger,kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611091613540.3501@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-25x86/microcode: Run the AP-loading routine only on the application processorsBorislav Petkov
cpu_init() is run also on the BSP (in addition to the APs): x86_64_start_kernel |-> x86_64_start_reservations |-> start_kernel |-> trap_init |-> cpu_init |-> load_ucode_ap ... but we run the AP (Application Processors) microcode loading routine there too even though we have a BSP-specific routine for that: load_ucode_bsp(). Which is unnecessary. So let's limit the AP microcode loading routine to the APs only. Remove a useless comment while at it. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161025095522.11964-2-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-25x86/cpu: Get rid of the show_msr= boot optionBorislav Petkov
It is useless as it dumps the MSRs too early BUT(!) we do set MSRs later too. Also, it dumps only BSP MSRs as it gets called only for CPU 0. And the MSR range array would need constant updating anyway, and so on and so on... Oh, and we have msr.ko and msr-tools which are the much better solution anyway. So off it goes... Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161024173844.23038-4-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-03Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull low-level x86 updates from Ingo Molnar: "In this cycle this topic tree has become one of those 'super topics' that accumulated a lot of changes: - Add CONFIG_VMAP_STACK=y support to the core kernel and enable it on x86 - preceded by an array of changes. v4.8 saw preparatory changes in this area already - this is the rest of the work. Includes the thread stack caching performance optimization. (Andy Lutomirski) - switch_to() cleanups and all around enhancements. (Brian Gerst) - A large number of dumpstack infrastructure enhancements and an unwinder abstraction. The secret long term plan is safe(r) live patching plus maybe another attempt at debuginfo based unwinding - but all these current bits are standalone enhancements in a frame pointer based debug environment as well. (Josh Poimboeuf) - More __ro_after_init and const annotations. (Kees Cook) - Enable KASLR for the vmemmap memory region. (Thomas Garnier)" [ The virtually mapped stack changes are pretty fundamental, and not x86-specific per se, even if they are only used on x86 right now. ] * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) x86/asm: Get rid of __read_cr4_safe() thread_info: Use unsigned long for flags x86/alternatives: Add stack frame dependency to alternative_call_2() x86/dumpstack: Fix show_stack() task pointer regression x86/dumpstack: Remove dump_trace() and related callbacks x86/dumpstack: Convert show_trace_log_lvl() to use the new unwinder oprofile/x86: Convert x86_backtrace() to use the new unwinder x86/stacktrace: Convert save_stack_trace_*() to use the new unwinder perf/x86: Convert perf_callchain_kernel() to use the new unwinder x86/unwind: Add new unwind interface and implementations x86/dumpstack: Remove NULL task pointer convention fork: Optimize task creation by caching two thread stacks per CPU if CONFIG_VMAP_STACK=y sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK lib/syscall: Pin the task stack in collect_syscall() x86/process: Pin the target stack in get_wchan() x86/dumpstack: Pin the target stack when dumping it kthread: Pin the stack via try_get_task_stack()/put_task_stack() in to_live_kthread() function sched/core: Add try_get_task_stack() and put_task_stack() x86/entry/64: Fix a minor comment rebase error iommu/amd: Don't put completion-wait semaphore on stack ...
2016-09-30x86/boot: Initialize FPU and X86_FEATURE_ALWAYS even if we don't have CPUIDAndy Lutomirski
Otherwise arch_task_struct_size == 0 and we die. While we're at it, set X86_FEATURE_ALWAYS, too. Reported-by: David Saggiorato <david@saggiorato.net> Tested-by: David Saggiorato <david@saggiorato.net> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.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: stable@vger.kernel.org Fixes: aaeb5c01c5b ("x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86") Link: http://lkml.kernel.org/r/8de723afbf0811071185039f9088733188b606c9.1475103911.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-08Merge branch 'x86/mm' into x86/asm, to unify the two branches for simplicityIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-24x86/entry: Remove outdated comment about SYSCALL targetsBorislav Petkov
The comment probably meant some old AMD64 incarnation which most likely never saw the light of day. STAR and LSTAR are two different registers and STAR sets CS/SS(DS) selectors for *all* modes, not only 32-bit. So simply remove that comment. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160823172356.15879-1-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>