kernel.git/arch/x86/kernel/alternative.c, branch linux-4.20.y

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

2018-10-23T16:54:58Z

Pull x86 paravirt updates from Ingo Molnar: "Two main changes: - Remove no longer used parts of the paravirt infrastructure and put large quantities of paravirt ops under a new config option PARAVIRT_XXL=y, which is selected by XEN_PV only. (Joergen Gross) - Enable PV spinlocks on Hyperv (Yi Sun)" * 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/hyperv: Enable PV qspinlock for Hyper-V x86/hyperv: Add GUEST_IDLE_MSR support x86/paravirt: Clean up native_patch() x86/paravirt: Prevent redefinition of SAVE_FLAGS macro x86/xen: Make xen_reservation_lock static x86/paravirt: Remove unneeded mmu related paravirt ops bits x86/paravirt: Move the Xen-only pv_mmu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the pv_irq_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move the Xen-only pv_cpu_ops under the PARAVIRT_XXL umbrella x86/paravirt: Move items in pv_info under PARAVIRT_XXL umbrella x86/paravirt: Introduce new config option PARAVIRT_XXL x86/paravirt: Remove unused paravirt bits x86/paravirt: Use a single ops structure x86/paravirt: Remove clobbers from struct paravirt_patch_site x86/paravirt: Remove clobbers parameter from paravirt patch functions x86/paravirt: Make paravirt_patch_call() and paravirt_patch_jmp() static x86/xen: Add SPDX identifier in arch/x86/xen files x86/xen: Link platform-pci-unplug.o only if CONFIG_XEN_PVHVM x86/xen: Move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c x86/xen: Move pv irq related functions under CONFIG_XEN_PV umbrella

x86/alternative: Init ideal_nops for Hygon Dhyana

2018-09-27T16:28:58Z

The ideal_nops for Hygon Dhyana CPU should be p6_nops. Signed-off-by: Pu Wen Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Cc: tglx@linutronix.de Cc: mingo@redhat.com Cc: hpa@zytor.com Cc: x86@kernel.org Cc: thomas.lendacky@amd.com Link: https://lkml.kernel.org/r/79e76c3173716984fe5fdd4a8e2c798bf4193205.1537533369.git.puwen@hygon.cn

x86/paravirt: Use a single ops structure

2018-09-03T14:50:35Z

Instead of using six globally visible paravirt ops structures combine them in a single structure, keeping the original structures as sub-structures. This avoids the need to assemble struct paravirt_patch_template at runtime on the stack each time apply_paravirt() is being called (i.e. when loading a module). [ tglx: Made the struct and the initializer tabular for readability sake ] Signed-off-by: Juergen Gross Signed-off-by: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: virtualization@lists.linux-foundation.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: boris.ostrovsky@oracle.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180828074026.820-9-jgross@suse.com

x86/paravirt: Remove clobbers parameter from paravirt patch functions

2018-09-03T14:50:34Z

The clobbers parameter from paravirt_patch_default() et al isn't used any longer. Remove it. Signed-off-by: Juergen Gross Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: virtualization@lists.linux-foundation.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: boris.ostrovsky@oracle.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180828074026.820-7-jgross@suse.com

x86/alternatives: Lockdep-enforce text_mutex in text_poke*()

2018-08-30T11:02:30Z

text_poke() and text_poke_bp() must be called with text_mutex held. Put proper lockdep anotation in place instead of just mentioning the requirement in a comment. Reported-by: Peter Zijlstra Signed-off-by: Jiri Kosina Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Acked-by: Masami Hiramatsu Cc: Andy Lutomirski Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1808280853520.25787@cbobk.fhfr.pm

x86/alternatives, jumplabel: Use text_poke_early() before mm_init()

2018-07-19T22:02:38Z

It supposed to be safe to modify static branches after jump_label_init(). But, because static key modifying code eventually calls text_poke() it can end up accessing a struct page which has not been initialized yet. Here is how to quickly reproduce the problem. Insert code like this into init/main.c: | +static DEFINE_STATIC_KEY_FALSE(__test); | asmlinkage __visible void __init start_kernel(void) | { | char *command_line; |@@ -587,6 +609,10 @@ asmlinkage __visible void __init start_kernel(void) | vfs_caches_init_early(); | sort_main_extable(); | trap_init(); |+ { |+ static_branch_enable(&__test); |+ WARN_ON(!static_branch_likely(&__test)); |+ } | mm_init(); The following warnings show-up: WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:701 text_poke+0x20d/0x230 RIP: 0010:text_poke+0x20d/0x230 Call Trace: ? text_poke_bp+0x50/0xda ? arch_jump_label_transform+0x89/0xe0 ? __jump_label_update+0x78/0xb0 ? static_key_enable_cpuslocked+0x4d/0x80 ? static_key_enable+0x11/0x20 ? start_kernel+0x23e/0x4c8 ? secondary_startup_64+0xa5/0xb0 ---[ end trace abdc99c031b8a90a ]--- If the code above is moved after mm_init(), no warning is shown, as struct pages are initialized during handover from memblock. Use text_poke_early() in static branching until early boot IRQs are enabled and from there switch to text_poke. Also, ensure text_poke() is never invoked when unitialized memory access may happen by using adding a !after_bootmem assertion. Signed-off-by: Pavel Tatashin Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: douly.fnst@cn.fujitsu.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-9-pasha.tatashin@oracle.com

x86/paravirt: Remove 'noreplace-paravirt' cmdline option

2018-01-31T09:37:45Z

The 'noreplace-paravirt' option disables paravirt patching, leaving the original pv indirect calls in place. That's highly incompatible with retpolines, unless we want to uglify paravirt even further and convert the paravirt calls to retpolines. As far as I can tell, the option doesn't seem to be useful for much other than introducing surprising corner cases and making the kernel vulnerable to Spectre v2. It was probably a debug option from the early paravirt days. So just remove it. Signed-off-by: Josh Poimboeuf Signed-off-by: Thomas Gleixner Reviewed-by: Juergen Gross Cc: Andrea Arcangeli Cc: Peter Zijlstra Cc: Andi Kleen Cc: Ashok Raj Cc: Greg KH Cc: Jun Nakajima Cc: Tim Chen Cc: Rusty Russell Cc: Dave Hansen Cc: Asit Mallick Cc: Andy Lutomirski Cc: Linus Torvalds Cc: Jason Baron Cc: Paolo Bonzini Cc: Alok Kataria Cc: Arjan Van De Ven Cc: David Woodhouse Cc: Dan Williams Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble

Merge tag 'v4.15' into x86/pti, to be able to merge dependent changes

2018-01-30T14:08:27Z

Time has come to switch PTI development over to a v4.15 base - we'll still try to make sure that all PTI fixes backport cleanly to v4.14 and earlier. Signed-off-by: Ingo Molnar

x86/alternative: Print unadorned pointers

2018-01-26T14:53:19Z

After commit ad67b74d2469 ("printk: hash addresses printed with %p") pointers are being hashed when printed. However, this makes the alternative debug output completely useless. Switch to %px in order to see the unadorned kernel pointers. Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: riel@redhat.com Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: David Woodhouse Cc: jikos@kernel.org Cc: luto@amacapital.net Cc: dave.hansen@intel.com Cc: torvalds@linux-foundation.org Cc: keescook@google.com Cc: Josh Poimboeuf Cc: tim.c.chen@linux.intel.com Cc: gregkh@linux-foundation.org Cc: pjt@google.com Link: https://lkml.kernel.org/r/20180126121139.31959-2-bp@alien8.de

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

2018-01-14T17:51:25Z

Pull x86 pti updates from Thomas Gleixner: "This contains: - a PTI bugfix to avoid setting reserved CR3 bits when PCID is disabled. This seems to cause issues on a virtual machine at least and is incorrect according to the AMD manual. - a PTI bugfix which disables the perf BTS facility if PTI is enabled. The BTS AUX buffer is not globally visible and causes the CPU to fault when the mapping disappears on switching CR3 to user space. A full fix which restores BTS on PTI is non trivial and will be worked on. - PTI bugfixes for EFI and trusted boot which make sure that the user space visible page table entries have the NX bit cleared - removal of dead code in the PTI pagetable setup functions - add PTI documentation - add a selftest for vsyscall to verify that the kernel actually implements what it advertises. - a sysfs interface to expose vulnerability and mitigation information so there is a coherent way for users to retrieve the status. - the initial spectre_v2 mitigations, aka retpoline: + The necessary ASM thunk and compiler support + The ASM variants of retpoline and the conversion of affected ASM code + Make LFENCE serializing on AMD so it can be used as speculation trap + The RSB fill after vmexit - initial objtool support for retpoline As I said in the status mail this is the most of the set of patches which should go into 4.15 except two straight forward patches still on hold: - the retpoline add on of LFENCE which waits for ACKs - the RSB fill after context switch Both should be ready to go early next week and with that we'll have covered the major holes of spectre_v2 and go back to normality" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) x86,perf: Disable intel_bts when PTI security/Kconfig: Correct the Documentation reference for PTI x86/pti: Fix !PCID and sanitize defines selftests/x86: Add test_vsyscall x86/retpoline: Fill return stack buffer on vmexit x86/retpoline/irq32: Convert assembler indirect jumps x86/retpoline/checksum32: Convert assembler indirect jumps x86/retpoline/xen: Convert Xen hypercall indirect jumps x86/retpoline/hyperv: Convert assembler indirect jumps x86/retpoline/ftrace: Convert ftrace assembler indirect jumps x86/retpoline/entry: Convert entry assembler indirect jumps x86/retpoline/crypto: Convert crypto assembler indirect jumps x86/spectre: Add boot time option to select Spectre v2 mitigation x86/retpoline: Add initial retpoline support objtool: Allow alternatives to be ignored objtool: Detect jumps to retpoline thunks x86/pti: Make unpoison of pgd for trusted boot work for real x86/alternatives: Fix optimize_nops() checking sysfs/cpu: Fix typos in vulnerability documentation x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC ...