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* Merge branch 'speck-v20' of ↵Linus Torvalds2018-05-216-21/+137
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Merge speculative store buffer bypass fixes from Thomas Gleixner: - rework of the SPEC_CTRL MSR management to accomodate the new fancy SSBD (Speculative Store Bypass Disable) bit handling. - the CPU bug and sysfs infrastructure for the exciting new Speculative Store Bypass 'feature'. - support for disabling SSB via LS_CFG MSR on AMD CPUs including Hyperthread synchronization on ZEN. - PRCTL support for dynamic runtime control of SSB - SECCOMP integration to automatically disable SSB for sandboxed processes with a filter flag for opt-out. - KVM integration to allow guests fiddling with SSBD including the new software MSR VIRT_SPEC_CTRL to handle the LS_CFG based oddities on AMD. - BPF protection against SSB .. this is just the core and x86 side, other architecture support will come separately. * 'speck-v20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits) bpf: Prevent memory disambiguation attack x86/bugs: Rename SSBD_NO to SSB_NO KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFG x86/bugs: Rework spec_ctrl base and mask logic x86/bugs: Remove x86_spec_ctrl_set() x86/bugs: Expose x86_spec_ctrl_base directly x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host} x86/speculation: Rework speculative_store_bypass_update() x86/speculation: Add virtualized speculative store bypass disable support x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL x86/speculation: Handle HT correctly on AMD x86/cpufeatures: Add FEATURE_ZEN x86/cpufeatures: Disentangle SSBD enumeration x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRS x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP KVM: SVM: Move spec control call after restore of GS x86/cpu: Make alternative_msr_write work for 32-bit code x86/bugs: Fix the parameters alignment and missing void x86/bugs: Make cpu_show_common() static ...
| * x86/bugs: Rename SSBD_NO to SSB_NOKonrad Rzeszutek Wilk2018-05-181-1/+1
| | | | | | | | | | | | | | | | The "336996 Speculative Execution Side Channel Mitigations" from May defines this as SSB_NO, hence lets sync-up. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBDTom Lendacky2018-05-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Expose the new virtualized architectural mechanism, VIRT_SSBD, for using speculative store bypass disable (SSBD) under SVM. This will allow guests to use SSBD on hardware that uses non-architectural mechanisms for enabling SSBD. [ tglx: Folded the migration fixup from Paolo Bonzini ] Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/speculation, KVM: Implement support for VIRT_SPEC_CTRL/LS_CFGThomas Gleixner2018-05-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | Add the necessary logic for supporting the emulated VIRT_SPEC_CTRL MSR to x86_virt_spec_ctrl(). If either X86_FEATURE_LS_CFG_SSBD or X86_FEATURE_VIRT_SPEC_CTRL is set then use the new guest_virt_spec_ctrl argument to check whether the state must be modified on the host. The update reuses speculative_store_bypass_update() so the ZEN-specific sibling coordination can be reused. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/bugs: Remove x86_spec_ctrl_set()Thomas Gleixner2018-05-171-2/+0
| | | | | | | | | | | | | | | | | | | | | | x86_spec_ctrl_set() is only used in bugs.c and the extra mask checks there provide no real value as both call sites can just write x86_spec_ctrl_base to MSR_SPEC_CTRL. x86_spec_ctrl_base is valid and does not need any extra masking or checking. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/bugs: Expose x86_spec_ctrl_base directlyThomas Gleixner2018-05-172-14/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | x86_spec_ctrl_base is the system wide default value for the SPEC_CTRL MSR. x86_spec_ctrl_get_default() returns x86_spec_ctrl_base and was intended to prevent modification to that variable. Though the variable is read only after init and globaly visible already. Remove the function and export the variable instead. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/bugs: Unify x86_spec_ctrl_{set_guest,restore_host}Borislav Petkov2018-05-171-4/+29
| | | | | | | | | | | | | | | | | | | | | | | | Function bodies are very similar and are going to grow more almost identical code. Add a bool arg to determine whether SPEC_CTRL is being set for the guest or restored to the host. No functional changes. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/speculation: Rework speculative_store_bypass_update()Thomas Gleixner2018-05-171-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | The upcoming support for the virtual SPEC_CTRL MSR on AMD needs to reuse speculative_store_bypass_update() to avoid code duplication. Add an argument for supplying a thread info (TIF) value and create a wrapper speculative_store_bypass_update_current() which is used at the existing call site. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/speculation: Add virtualized speculative store bypass disable supportTom Lendacky2018-05-172-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some AMD processors only support a non-architectural means of enabling speculative store bypass disable (SSBD). To allow a simplified view of this to a guest, an architectural definition has been created through a new CPUID bit, 0x80000008_EBX[25], and a new MSR, 0xc001011f. With this, a hypervisor can virtualize the existence of this definition and provide an architectural method for using SSBD to a guest. Add the new CPUID feature, the new MSR and update the existing SSBD support to use this MSR when present. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de>
| * x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRLThomas Gleixner2018-05-171-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AMD is proposing a VIRT_SPEC_CTRL MSR to handle the Speculative Store Bypass Disable via MSR_AMD64_LS_CFG so that guests do not have to care about the bit position of the SSBD bit and thus facilitate migration. Also, the sibling coordination on Family 17H CPUs can only be done on the host. Extend x86_spec_ctrl_set_guest() and x86_spec_ctrl_restore_host() with an extra argument for the VIRT_SPEC_CTRL MSR. Hand in 0 from VMX and in SVM add a new virt_spec_ctrl member to the CPU data structure which is going to be used in later patches for the actual implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/speculation: Handle HT correctly on AMDThomas Gleixner2018-05-171-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The AMD64_LS_CFG MSR is a per core MSR on Family 17H CPUs. That means when hyperthreading is enabled the SSBD bit toggle needs to take both cores into account. Otherwise the following situation can happen: CPU0 CPU1 disable SSB disable SSB enable SSB <- Enables it for the Core, i.e. for CPU0 as well So after the SSB enable on CPU1 the task on CPU0 runs with SSB enabled again. On Intel the SSBD control is per core as well, but the synchronization logic is implemented behind the per thread SPEC_CTRL MSR. It works like this: CORE_SPEC_CTRL = THREAD0_SPEC_CTRL | THREAD1_SPEC_CTRL i.e. if one of the threads enables a mitigation then this affects both and the mitigation is only disabled in the core when both threads disabled it. Add the necessary synchronization logic for AMD family 17H. Unfortunately that requires a spinlock to serialize the access to the MSR, but the locks are only shared between siblings. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/cpufeatures: Add FEATURE_ZENThomas Gleixner2018-05-171-0/+1
| | | | | | | | | | | | | | | | | | Add a ZEN feature bit so family-dependent static_cpu_has() optimizations can be built for ZEN. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/cpufeatures: Disentangle SSBD enumerationThomas Gleixner2018-05-171-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SSBD enumeration is similarly to the other bits magically shared between Intel and AMD though the mechanisms are different. Make X86_FEATURE_SSBD synthetic and set it depending on the vendor specific features or family dependent setup. Change the Intel bit to X86_FEATURE_SPEC_CTRL_SSBD to denote that SSBD is controlled via MSR_SPEC_CTRL and fix up the usage sites. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/cpufeatures: Disentangle MSR_SPEC_CTRL enumeration from IBRSThomas Gleixner2018-05-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The availability of the SPEC_CTRL MSR is enumerated by a CPUID bit on Intel and implied by IBRS or STIBP support on AMD. That's just confusing and in case an AMD CPU has IBRS not supported because the underlying problem has been fixed but has another bit valid in the SPEC_CTRL MSR, the thing falls apart. Add a synthetic feature bit X86_FEATURE_MSR_SPEC_CTRL to denote the availability on both Intel and AMD. While at it replace the boot_cpu_has() checks with static_cpu_has() where possible. This prevents late microcode loading from exposing SPEC_CTRL, but late loading is already very limited as it does not reevaluate the mitigation options and other bits and pieces. Having static_cpu_has() is the simplest and least fragile solution. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/speculation: Use synthetic bits for IBRS/IBPB/STIBPBorislav Petkov2018-05-171-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel and AMD have different CPUID bits hence for those use synthetic bits which get set on the respective vendor's in init_speculation_control(). So that debacles like what the commit message of c65732e4f721 ("x86/cpu: Restore CPUID_8000_0008_EBX reload") talks about don't happen anymore. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Jörg Otte <jrg.otte@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/20180504161815.GG9257@pd.tnic
| * x86/cpu: Make alternative_msr_write work for 32-bit codeJim Mattson2018-05-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Cast val and (val >> 32) to (u32), so that they fit in a general-purpose register in both 32-bit and 64-bit code. [ tglx: Made it u32 instead of uintptr_t ] Fixes: c65732e4f721 ("x86/cpu: Restore CPUID_8000_0008_EBX reload") Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
| * x86/bugs: Rename _RDS to _SSBDKonrad Rzeszutek Wilk2018-05-094-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel collateral will reference the SSB mitigation bit in IA32_SPEC_CTL[2] as SSBD (Speculative Store Bypass Disable). Hence changing it. It is unclear yet what the MSR_IA32_ARCH_CAPABILITIES (0x10a) Bit(4) name is going to be. Following the rename it would be SSBD_NO but that rolls out to Speculative Store Bypass Disable No. Also fixed the missing space in X86_FEATURE_AMD_SSBD. [ tglx: Fixup x86_amd_rds_enable() and rds_tif_to_amd_ls_cfg() as well ] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/speculation: Make "seccomp" the default mode for Speculative Store BypassKees Cook2018-05-051-0/+1
| | | | | | | | | | | | | | | | | | | | Unless explicitly opted out of, anything running under seccomp will have SSB mitigations enabled. Choosing the "prctl" mode will disable this. [ tglx: Adjusted it to the new arch_seccomp_spec_mitigate() mechanism ] Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/speculation: Add prctl for Speculative Store Bypass mitigationThomas Gleixner2018-05-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add prctl based control for Speculative Store Bypass mitigation and make it the default mitigation for Intel and AMD. Andi Kleen provided the following rationale (slightly redacted): There are multiple levels of impact of Speculative Store Bypass: 1) JITed sandbox. It cannot invoke system calls, but can do PRIME+PROBE and may have call interfaces to other code 2) Native code process. No protection inside the process at this level. 3) Kernel. 4) Between processes. The prctl tries to protect against case (1) doing attacks. If the untrusted code can do random system calls then control is already lost in a much worse way. So there needs to be system call protection in some way (using a JIT not allowing them or seccomp). Or rather if the process can subvert its environment somehow to do the prctl it can already execute arbitrary code, which is much worse than SSB. To put it differently, the point of the prctl is to not allow JITed code to read data it shouldn't read from its JITed sandbox. If it already has escaped its sandbox then it can already read everything it wants in its address space, and do much worse. The ability to control Speculative Store Bypass allows to enable the protection selectively without affecting overall system performance. Based on an initial patch from Tim Chen. Completely rewritten. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/process: Allow runtime control of Speculative Store BypassThomas Gleixner2018-05-033-2/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Speculative Store Bypass vulnerability can be mitigated with the Reduced Data Speculation (RDS) feature. To allow finer grained control of this eventually expensive mitigation a per task mitigation control is required. Add a new TIF_RDS flag and put it into the group of TIF flags which are evaluated for mismatch in switch_to(). If these bits differ in the previous and the next task, then the slow path function __switch_to_xtra() is invoked. Implement the TIF_RDS dependent mitigation control in the slow path. If the prctl for controlling Speculative Store Bypass is disabled or no task uses the prctl then there is no overhead in the switch_to() fast path. Update the KVM related speculation control functions to take TID_RDS into account as well. Based on a patch from Tim Chen. Completely rewritten. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| * x86/speculation: Create spec-ctrl.h to avoid include hellThomas Gleixner2018-05-032-14/+21
| | | | | | | | | | | | | | | | | | | | | | Having everything in nospec-branch.h creates a hell of dependencies when adding the prctl based switching mechanism. Move everything which is not required in nospec-branch.h to spec-ctrl.h and fix up the includes in the relevant files. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs/AMD: Add support to disable RDS on Fam[15,16,17]h if requestedKonrad Rzeszutek Wilk2018-05-032-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AMD does not need the Speculative Store Bypass mitigation to be enabled. The parameters for this are already available and can be done via MSR C001_1020. Each family uses a different bit in that MSR for this. [ tglx: Expose the bit mask via a variable and move the actual MSR fiddling into the bugs code as that's the right thing to do and also required to prepare for dynamic enable/disable ] Suggested-by: Borislav Petkov <bp@suse.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs/intel: Set proper CPU features and setup RDSKonrad Rzeszutek Wilk2018-05-031-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel CPUs expose methods to: - Detect whether RDS capability is available via CPUID.7.0.EDX[31], - The SPEC_CTRL MSR(0x48), bit 2 set to enable RDS. - MSR_IA32_ARCH_CAPABILITIES, Bit(4) no need to enable RRS. With that in mind if spec_store_bypass_disable=[auto,on] is selected set at boot-time the SPEC_CTRL MSR to enable RDS if the platform requires it. Note that this does not fix the KVM case where the SPEC_CTRL is exposed to guests which can muck with it, see patch titled : KVM/SVM/VMX/x86/spectre_v2: Support the combination of guest and host IBRS. And for the firmware (IBRS to be set), see patch titled: x86/spectre_v2: Read SPEC_CTRL MSR during boot and re-use reserved bits [ tglx: Distangled it from the intel implementation and kept the call order ] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigationKonrad Rzeszutek Wilk2018-05-032-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Contemporary high performance processors use a common industry-wide optimization known as "Speculative Store Bypass" in which loads from addresses to which a recent store has occurred may (speculatively) see an older value. Intel refers to this feature as "Memory Disambiguation" which is part of their "Smart Memory Access" capability. Memory Disambiguation can expose a cache side-channel attack against such speculatively read values. An attacker can create exploit code that allows them to read memory outside of a sandbox environment (for example, malicious JavaScript in a web page), or to perform more complex attacks against code running within the same privilege level, e.g. via the stack. As a first step to mitigate against such attacks, provide two boot command line control knobs: nospec_store_bypass_disable spec_store_bypass_disable=[off,auto,on] By default affected x86 processors will power on with Speculative Store Bypass enabled. Hence the provided kernel parameters are written from the point of view of whether to enable a mitigation or not. The parameters are as follows: - auto - Kernel detects whether your CPU model contains an implementation of Speculative Store Bypass and picks the most appropriate mitigation. - on - disable Speculative Store Bypass - off - enable Speculative Store Bypass [ tglx: Reordered the checks so that the whole evaluation is not done when the CPU does not support RDS ] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/cpufeatures: Add X86_FEATURE_RDSKonrad Rzeszutek Wilk2018-05-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | Add the CPU feature bit CPUID.7.0.EDX[31] which indicates whether the CPU supports Reduced Data Speculation. [ tglx: Split it out from a later patch ] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs: Expose /sys/../spec_store_bypassKonrad Rzeszutek Wilk2018-05-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the sysfs file for the new vulerability. It does not do much except show the words 'Vulnerable' for recent x86 cores. Intel cores prior to family 6 are known not to be vulnerable, and so are some Atoms and some Xeon Phi. It assumes that older Cyrix, Centaur, etc. cores are immune. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs, KVM: Support the combination of guest and host IBRSKonrad Rzeszutek Wilk2018-05-031-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A guest may modify the SPEC_CTRL MSR from the value used by the kernel. Since the kernel doesn't use IBRS, this means a value of zero is what is needed in the host. But the 336996-Speculative-Execution-Side-Channel-Mitigations.pdf refers to the other bits as reserved so the kernel should respect the boot time SPEC_CTRL value and use that. This allows to deal with future extensions to the SPEC_CTRL interface if any at all. Note: This uses wrmsrl() instead of native_wrmsl(). I does not make any difference as paravirt will over-write the callq *0xfff.. with the wrmsrl assembler code. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bitsKonrad Rzeszutek Wilk2018-05-031-4/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 336996-Speculative-Execution-Side-Channel-Mitigations.pdf refers to all the other bits as reserved. The Intel SDM glossary defines reserved as implementation specific - aka unknown. As such at bootup this must be taken it into account and proper masking for the bits in use applied. A copy of this document is available at https://bugzilla.kernel.org/show_bug.cgi?id=199511 [ tglx: Made x86_spec_ctrl_base __ro_after_init ] Suggested-by: Jon Masters <jcm@redhat.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
| * x86/nospec: Simplify alternative_msr_write()Linus Torvalds2018-05-031-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The macro is not type safe and I did look for why that "g" constraint for the asm doesn't work: it's because the asm is more fundamentally wrong. It does movl %[val], %%eax but "val" isn't a 32-bit value, so then gcc will pass it in a register, and generate code like movl %rsi, %eax and gas will complain about a nonsensical 'mov' instruction (it's moving a 64-bit register to a 32-bit one). Passing it through memory will just hide the real bug - gcc still thinks the memory location is 64-bit, but the "movl" will only load the first 32 bits and it all happens to work because x86 is little-endian. Convert it to a type safe inline function with a little trick which hands the feature into the ALTERNATIVE macro. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-05-202-5/+15
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "An unfortunately larger set of fixes, but a large portion is selftests: - Fix the missing clusterid initializaiton for x2apic cluster management which caused boot failures due to IPIs being sent to the wrong cluster - Drop TX_COMPAT when a 64bit executable is exec()'ed from a compat task - Wrap access to __supported_pte_mask in __startup_64() where clang compile fails due to a non PC relative access being generated. - Two fixes for 5 level paging fallout in the decompressor: - Handle GOT correctly for paging_prepare() and cleanup_trampoline() - Fix the page table handling in cleanup_trampoline() to avoid page table corruption. - Stop special casing protection key 0 as this is inconsistent with the manpage and also inconsistent with the allocation map handling. - Override the protection key wen moving away from PROT_EXEC to prevent inaccessible memory. - Fix and update the protection key selftests to address breakage and to cover the above issue - Add a MOV SS self test" [ Part of the x86 fixes were in the earlier core pull due to dependencies ] * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86/mm: Drop TS_COMPAT on 64-bit exec() syscall x86/apic/x2apic: Initialize cluster ID properly x86/boot/compressed/64: Fix moving page table out of trampoline memory x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline() x86/pkeys: Do not special case protection key 0 x86/pkeys/selftests: Add a test for pkey 0 x86/pkeys/selftests: Save off 'prot' for allocations x86/pkeys/selftests: Fix pointer math x86/pkeys: Override pkey when moving away from PROT_EXEC x86/pkeys/selftests: Fix pkey exhaustion test off-by-one x86/pkeys/selftests: Add PROT_EXEC test x86/pkeys/selftests: Factor out "instruction page" x86/pkeys/selftests: Allow faults on unknown keys x86/pkeys/selftests: Avoid printf-in-signal deadlocks x86/pkeys/selftests: Remove dead debugging code, fix dprint_in_signal x86/pkeys/selftests: Stop using assert() x86/pkeys/selftests: Give better unexpected fault error messages x86/selftests: Add mov_to_ss test x86/mpx/selftests: Adjust the self-test to fresh distros that export the MPX ABI x86/pkeys/selftests: Adjust the self-test to fresh distros that export the pkeys ABI ...
| * | x86/pkeys: Do not special case protection key 0Dave Hansen2018-05-142-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mm_pkey_is_allocated() treats pkey 0 as unallocated. That is inconsistent with the manpages, and also inconsistent with mm->context.pkey_allocation_map. Stop special casing it and only disallow values that are actually bad (< 0). The end-user visible effect of this is that you can now use mprotect_pkey() to set pkey=0. This is a bit nicer than what Ram proposed[1] because it is simpler and removes special-casing for pkey 0. On the other hand, it does allow applications to pkey_free() pkey-0, but that's just a silly thing to do, so we are not going to protect against it. The scenario that could happen is similar to what happens if you free any other pkey that is in use: it might get reallocated later and used to protect some other data. The most likely scenario is that pkey-0 comes back from pkey_alloc(), an access-disable or write-disable bit is set in PKRU for it, and the next stack access will SIGSEGV. It's not horribly different from if you mprotect()'d your stack or heap to be unreadable or unwritable, which is generally very foolish, but also not explicitly prevented by the kernel. 1. http://lkml.kernel.org/r/1522112702-27853-1-git-send-email-linuxram@us.ibm.com Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org>p Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellermen <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ram Pai <linuxram@us.ibm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: stable@vger.kernel.org Fixes: 58ab9a088dda ("x86/pkeys: Check against max pkey to avoid overflows") Link: http://lkml.kernel.org/r/20180509171358.47FD785E@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | x86/pkeys: Override pkey when moving away from PROT_EXECDave Hansen2018-05-141-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I got a bug report that the following code (roughly) was causing a SIGSEGV: mprotect(ptr, size, PROT_EXEC); mprotect(ptr, size, PROT_NONE); mprotect(ptr, size, PROT_READ); *ptr = 100; The problem is hit when the mprotect(PROT_EXEC) is implicitly assigned a protection key to the VMA, and made that key ACCESS_DENY|WRITE_DENY. The PROT_NONE mprotect() failed to remove the protection key, and the PROT_NONE-> PROT_READ left the PTE usable, but the pkey still in place and left the memory inaccessible. To fix this, we ensure that we always "override" the pkee at mprotect() if the VMA does not have execute-only permissions, but the VMA has the execute-only pkey. We had a check for PROT_READ/WRITE, but it did not work for PROT_NONE. This entirely removes the PROT_* checks, which ensures that PROT_NONE now works. Reported-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellermen <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ram Pai <linuxram@us.ibm.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: stable@vger.kernel.org Fixes: 62b5f7d013f ("mm/core, x86/mm/pkeys: Add execute-only protection keys support") Link: http://lkml.kernel.org/r/20180509171351.084C5A71@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2018-05-202-0/+33
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core fixes from Thomas Gleixner: - Unbreak the BPF compilation which got broken by the unconditional requirement of asm-goto, which is not supported by clang. - Prevent probing on exception masking instructions in uprobes and kprobes to avoid the issues of the delayed exceptions instead of having an ugly workaround. - Prevent a double free_page() in the error path of do_kexec_load() - A set of objtool updates addressing various issues mostly related to switch tables and the noreturn detection for recursive sibling calls - Header sync for tools. * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Detect RIP-relative switch table references, part 2 objtool: Detect RIP-relative switch table references objtool: Support GCC 8 switch tables objtool: Support GCC 8's cold subfunctions objtool: Fix "noreturn" detection for recursive sibling calls objtool, kprobes/x86: Sync the latest <asm/insn.h> header with tools/objtool/arch/x86/include/asm/insn.h x86/cpufeature: Guard asm_volatile_goto usage for BPF compilation uprobes/x86: Prohibit probing on MOV SS instruction kprobes/x86: Prohibit probing on exception masking instructions x86/kexec: Avoid double free_page() upon do_kexec_load() failure
| * | x86/cpufeature: Guard asm_volatile_goto usage for BPF compilationAlexei Starovoitov2018-05-131-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Workaround for the sake of BPF compilation which utilizes kernel headers, but clang does not support ASM GOTO and fails the build. Fixes: d0266046ad54 ("x86: Remove FAST_FEATURE_TESTS") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: daniel@iogearbox.net Cc: peterz@infradead.org Cc: netdev@vger.kernel.org Cc: bp@alien8.de Cc: yhs@fb.com Cc: kernel-team@fb.com Cc: torvalds@linux-foundation.org Cc: davem@davemloft.net Link: https://lkml.kernel.org/r/20180513193222.1997938-1-ast@kernel.org
| * | kprobes/x86: Prohibit probing on exception masking instructionsMasami Hiramatsu2018-05-131-0/+18
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since MOV SS and POP SS instructions will delay the exceptions until the next instruction is executed, single-stepping on it by kprobes must be prohibited. However, kprobes usually executes those instructions directly on trampoline buffer (a.k.a. kprobe-booster), except for the kprobes which has post_handler. Thus if kprobe user probes MOV SS with post_handler, it will do single-stepping on the MOV SS. This means it is safe that if it is used via ftrace or perf/bpf since those don't use the post_handler. Anyway, since the stack switching is a rare case, it is safer just rejecting kprobes on such instructions. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Francis Deslauriers <francis.deslauriers@efficios.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Yonghong Song <yhs@fb.com> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "David S . Miller" <davem@davemloft.net> Link: https://lkml.kernel.org/r/152587069574.17316.3311695234863248641.stgit@devbox
* / kvm: rename KVM_HINTS_DEDICATED to KVM_HINTS_REALTIMEMichael S. Tsirkin2018-05-171-1/+1
|/ | | | | | | | | | | | | | | | | | | | KVM_HINTS_DEDICATED seems to be somewhat confusing: Guest doesn't really care whether it's the only task running on a host CPU as long as it's not preempted. And there are more reasons for Guest to be preempted than host CPU sharing, for example, with memory overcommit it can get preempted on a memory access, post copy migration can cause preemption, etc. Let's call it KVM_HINTS_REALTIME which seems to better match what guests expect. Also, the flag most be set on all vCPUs - current guests assume this. Note so in the documentation. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-04-296-12/+79
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Another set of x86 related updates: - Fix the long broken x32 version of the IPC user space headers which was noticed by Arnd Bergman in course of his ongoing y2038 work. GLIBC seems to have non broken private copies of these headers so this went unnoticed. - Two microcode fixlets which address some more fallout from the recent modifications in that area: - Unconditionally save the microcode patch, which was only saved when CPU_HOTPLUG was enabled causing failures in the late loading mechanism - Make the later loader synchronization finally work under all circumstances. It was exiting early and causing timeout failures due to a missing synchronization point. - Do not use mwait_play_dead() on AMD systems to prevent excessive power consumption as the CPU cannot go into deep power states from there. - Address an annoying sparse warning due to lost type qualifiers of the vmemmap and vmalloc base address constants. - Prevent reserving crash kernel region on Xen PV as this leads to the wrong perception that crash kernels actually work there which is not the case. Xen PV has its own crash mechanism handled by the hypervisor. - Add missing TLB cpuid values to the table to make the printout on certain machines correct. - Enumerate the new CLDEMOTE instruction - Fix an incorrect SPDX identifier - Remove stale macros" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds x86/setup: Do not reserve a crash kernel region if booted on Xen PV x86/cpu/intel: Add missing TLB cpuid values x86/smpboot: Don't use mwait_play_dead() on AMD systems x86/mm: Make vmemmap and vmalloc base address constants unsigned long x86/vector: Remove the unused macro FPU_IRQ x86/vector: Remove the macro VECTOR_OFFSET_START x86/cpufeatures: Enumerate cldemote instruction x86/microcode: Do not exit early from __reload_late() x86/microcode/intel: Save microcode patch unconditionally x86/jailhouse: Fix incorrect SPDX identifier
| * x86/ipc: Fix x32 version of shmid64_ds and msqid64_dsArnd Bergmann2018-04-272-0/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A bugfix broke the x32 shmid64_ds and msqid64_ds data structure layout (as seen from user space) a few years ago: Originally, __BITS_PER_LONG was defined as 64 on x32, so we did not have padding after the 64-bit __kernel_time_t fields, After __BITS_PER_LONG got changed to 32, applications would observe extra padding. In other parts of the uapi headers we seem to have a mix of those expecting either 32 or 64 on x32 applications, so we can't easily revert the path that broke these two structures. Instead, this patch decouples x32 from the other architectures and moves it back into arch specific headers, partially reverting the even older commit 73a2d096fdf2 ("x86: remove all now-duplicate header files"). It's not clear whether this ever made any difference, since at least glibc carries its own (correct) copy of both of these header files, so possibly no application has ever observed the definitions here. Based on a suggestion from H.J. Lu, I tried out the tool from https://github.com/hjl-tools/linux-header to find other such bugs, which pointed out the same bug in statfs(), which also has a separate (correct) copy in glibc. Fixes: f4b4aae18288 ("x86/headers/uapi: Fix __BITS_PER_LONG value for x32 builds") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "H . J . Lu" <hjl.tools@gmail.com> Cc: Jeffrey Walton <noloader@gmail.com> Cc: stable@vger.kernel.org Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/20180424212013.3967461-1-arnd@arndb.de
| * x86/mm: Make vmemmap and vmalloc base address constants unsigned longJiri Kosina2018-04-261-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 9b46a051e4 ("x86/mm: Initialize vmemmap_base at boot-time") and a7412546d8 ("x86/mm: Adjust vmalloc base and size at boot-time") lost the type information for __VMALLOC_BASE_L4, __VMALLOC_BASE_L5, __VMEMMAP_BASE_L4 and __VMEMMAP_BASE_L5 constants. Declare them explicitly unsigned long again. Fixes: 9b46a051e4 ("x86/mm: Initialize vmemmap_base at boot-time") Fixes: a7412546d8 ("x86/mm: Adjust vmalloc base and size at boot-time") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1804121437350.28129@cbobk.fhfr.pm
| * x86/vector: Remove the unused macro FPU_IRQDou Liyang2018-04-261-2/+0
| | | | | | | | | | | | | | | | | | | | The macro FPU_IRQ has never been used since v3.10, So remove it. Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180426060832.27312-1-douly.fnst@cn.fujitsu.com
| * x86/vector: Remove the macro VECTOR_OFFSET_STARTDou Liyang2018-04-261-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now, Linux uses matrix allocator for vector assignment, the original assignment code which used VECTOR_OFFSET_START has been removed. So remove the stale macro as well. Fixes: commit 69cde0004a4b ("x86/vector: Use matrix allocator for vector assignment") Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Rientjes <rientjes@google.com> Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180425020553.17210-1-douly.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/cpufeatures: Enumerate cldemote instructionFenghua Yu2018-04-261-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cldemote is a new instruction in future x86 processors. It hints to hardware that a specified cache line should be moved ("demoted") from the cache(s) closest to the processor core to a level more distant from the processor core. This instruction is faster than snooping to make the cache line available for other cores. cldemote instruction is indicated by the presence of the CPUID feature flag CLDEMOTE (CPUID.(EAX=0x7, ECX=0):ECX[bit25]). More details on cldemote instruction can be found in the latest Intel Architecture Instruction Set Extensions and Future Features Programming Reference. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com> Cc: "H. Peter Anvin" <hpa@linux.intel.com> Cc: "Ashok Raj" <ashok.raj@intel.com> Link: https://lkml.kernel.org/r/1524508162-192587-1-git-send-email-fenghua.yu@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/jailhouse: Fix incorrect SPDX identifierThomas Gleixner2018-04-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | GPL2.0 is not a valid SPDX identiier. Replace it with GPL-2.0. Fixes: 4a362601baa6 ("x86/jailhouse: Add infrastructure for running in non-root cell") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Link: https://lkml.kernel.org/r/20180422220832.815346488@linutronix.de
* | Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-04-291-0/+5
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 pti fixes from Thomas Gleixner: "A set of updates for the x86/pti related code: - Preserve r8-r11 in int $0x80. r8-r11 need to be preserved, but the int$80 entry code removed that quite some time ago. Make it correct again. - A set of fixes for the Global Bit work which went into 4.17 and caused a bunch of interesting regressions: - Triggering a BUG in the page attribute code due to a missing check for early boot stage - Warnings in the page attribute code about holes in the kernel text mapping which are caused by the freeing of the init code. Handle such holes gracefully. - Reduce the amount of kernel memory which is set global to the actual text and do not incidentally overlap with data. - Disable the global bit when RANDSTRUCT is enabled as it partially defeats the hardening. - Make the page protection setup correct for vma->page_prot population again. The adjustment of the protections fell through the crack during the Global bit rework and triggers warnings on machines which do not support certain features, e.g. NX" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry/64/compat: Preserve r8-r11 in int $0x80 x86/pti: Filter at vma->vm_page_prot population x86/pti: Disallow global kernel text with RANDSTRUCT x86/pti: Reduce amount of kernel text allowed to be Global x86/pti: Fix boot warning from Global-bit setting x86/pti: Fix boot problems from Global-bit setting
| * | x86/pti: Filter at vma->vm_page_prot populationDave Hansen2018-04-251-0/+5
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ce9962bf7e22bb3891655c349faff618922d4a73 0day reported warnings at boot on 32-bit systems without NX support: attempted to set unsupported pgprot: 8000000000000025 bits: 8000000000000000 supported: 7fffffffffffffff WARNING: CPU: 0 PID: 1 at arch/x86/include/asm/pgtable.h:540 handle_mm_fault+0xfc1/0xfe0: check_pgprot at arch/x86/include/asm/pgtable.h:535 (inlined by) pfn_pte at arch/x86/include/asm/pgtable.h:549 (inlined by) do_anonymous_page at mm/memory.c:3169 (inlined by) handle_pte_fault at mm/memory.c:3961 (inlined by) __handle_mm_fault at mm/memory.c:4087 (inlined by) handle_mm_fault at mm/memory.c:4124 The problem is that due to the recent commit which removed auto-massaging of page protections, filtering page permissions at PTE creation time is not longer done, so vma->vm_page_prot is passed unfiltered to PTE creation. Filter the page protections before they are installed in vma->vm_page_prot. Fixes: fb43d6cb91 ("x86/mm: Do not auto-massage page protections") Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kees Cook <keescook@google.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Nadav Amit <namit@vmware.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Link: https://lkml.kernel.org/r/20180420222028.99D72858@viggo.jf.intel.com
* | Merge tag 'trace-v4.17-rc1' of ↵Linus Torvalds2018-04-261-2/+17
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Add workqueue forward declaration (for new work, but a nice clean up) - seftest fixes for the new histogram code - Print output fix for hwlat tracer - Fix missing system call events - due to change in x86 syscall naming - Fix kprobe address being used by perf being hashed * tag 'trace-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix missing tab for hwlat_detector print format selftests: ftrace: Add a testcase for multiple actions on trigger selftests: ftrace: Fix trigger extended error testcase kprobes: Fix random address output of blacklist file tracing: Fix kernel crash while using empty filter with perf tracing/x86: Update syscall trace events to handle new prefixed syscall func names tracing: Add missing forward declaration
| * tracing/x86: Update syscall trace events to handle new prefixed syscall func ↵Steven Rostedt (VMware)2018-04-251-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | names Arnaldo noticed that the latest kernel is missing the syscall event system directory in x86. I bisected it down to d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()"). The system call trace events are special, as there is only one trace event for all system calls (the raw_syscalls). But a macro that wraps the system calls creates meta data for them that copies the name to find the system call that maps to the system call table (the number). At boot up, it does a kallsyms lookup of the system call table to find the function that maps to the meta data of the system call. If it does not find a function, then that system call is ignored. Because the x86 system calls had "__x64_", or "__ia32_" prefixed to the "sys" for the names, they do not match the default compare algorithm. As this was a problem for power pc, the algorithm can be overwritten by the architecture. The solution is to have x86 have its own algorithm to do the compare and this brings back the system call trace events. Link: http://lkml.kernel.org/r/20180417174128.0f3457f0@gandalf.local.home Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Fixes: d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2018-04-221-2/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A small set of fixes for x86: - Prevent X2APIC ID 0xFFFFFFFF from being treated as valid, which causes the possible CPU count to be wrong. - Prevent 32bit truncation in calc_hpet_ref() which causes the TSC calibration to fail - Fix the page table setup for temporary text mappings in the resume code which causes resume failures - Make the page table dump code handle HIGHPTE correctly instead of oopsing - Support for topologies where NUMA nodes share an LLC to prevent a invalid topology warning and further malfunction on such systems. - Remove the now unused pci-nommu code - Remove stale function declarations" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/power/64: Fix page-table setup for temporary text mapping x86/mm: Prevent kernel Oops in PTDUMP code with HIGHPTE=y x86,sched: Allow topologies where NUMA nodes share an LLC x86/processor: Remove two unused function declarations x86/acpi: Prevent X2APIC id 0xffffffff from being accounted x86/tsc: Prevent 32bit truncation in calc_hpet_ref() x86: Remove pci-nommu.c
| * | x86/processor: Remove two unused function declarationsDou Liyang2018-04-171-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | early_trap_init() and cpu_set_gdt() have been removed, so remove the stale declarations as well. Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Cc: luto@kernel.org Cc: hpa@zytor.com Cc: bp@suse.de Cc: kirill.shutemov@linux.intel.com Link: https://lkml.kernel.org/r/20180404064527.10562-1-douly.fnst@cn.fujitsu.com
* | | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2018-04-221-2/+0
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "A larger set of updates for perf. Kernel: - Handle the SBOX uncore monitoring correctly on Broadwell CPUs which do not have SBOX. - Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]. The percentage of preempting and non-preempting context switches help understanding the nature of workloads (CPU or IO bound) that are running on a machine. This adds the kernel facility and userspace changes needed to show this information in 'perf script' and 'perf report -D' (Alexey Budankov) - Remove a WARN_ON() in the trace/kprobes code which is pointless because the return error code is already telling the caller what's wrong. - Revert a fugly workaround for clang BPF targets. - Fix sample_max_stack maximum check and do not proceed when an error has been detect, return them to avoid misidentifying errors (Jiri Olsa) - Add SPDX idenitifiers and get rid of GPL boilderplate. Tools: - Synchronize kernel ABI headers, v4.17-rc1 (Ingo Molnar) - Support MAP_FIXED_NOREPLACE, noticed when updating the tools/include/ copies (Arnaldo Carvalho de Melo) - Add '\n' at the end of parse-options error messages (Ravi Bangoria) - Add s390 support for detailed/verbose PMU event description (Thomas Richter) - perf annotate fixes and improvements: * Allow showing offsets in more than just jump targets, use the new 'O' hotkey in the TUI, config ~/.perfconfig annotate.offset_level for it and for --stdio2 (Arnaldo Carvalho de Melo) * Use the resolved variable names from objdump disassembled lines to make them more compact, just like was already done for some instructions, like "mov", this eventually will be done more generally, but lets now add some more to the existing mechanism (Arnaldo Carvalho de Melo) - perf record fixes: * Change warning for missing topology sysfs entry to debug, as not all architectures have those files, s390 being one of those (Thomas Richter) * Remove old error messages about things that unlikely to be the root cause in modern systems (Andi Kleen) - perf sched fixes: * Fix -g/--call-graph documentation (Takuya Yamamoto) - perf stat: * Enable 1ms interval for printing event counters values in (Alexey Budankov) - perf test fixes: * Run dwarf unwind on arm32 (Kim Phillips) * Remove unused ptrace.h include from LLVM test, sidesteping older clang's lack of support for some asm constructs (Arnaldo Carvalho de Melo) * Fixup BPF test using epoll_pwait syscall function probe, to cope with the syscall routines renames performed in this development cycle (Arnaldo Carvalho de Melo) - perf version fixes: * Do not print info about HAVE_LIBAUDIT_SUPPORT in 'perf version --build-options' when HAVE_SYSCALL_TABLE_SUPPORT is true, as libaudit won't be used in that case, print info about syscall_table support instead (Jin Yao) - Build system fixes: * Use HAVE_..._SUPPORT used consistently (Jin Yao) * Restore READ_ONCE() C++ compatibility in tools/include (Mark Rutland) * Give hints about package names needed to build jvmti (Arnaldo Carvalho de Melo)" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) perf/x86/intel/uncore: Fix SBOX support for Broadwell CPUs perf/x86/intel/uncore: Revert "Remove SBOX support for Broadwell server" coresight: Move to SPDX identifier perf test BPF: Fixup BPF test using epoll_pwait syscall function probe perf tests mmap: Show which tracepoint is failing perf tools: Add '\n' at the end of parse-options error messages perf record: Remove suggestion to enable APIC perf record: Remove misleading error suggestion perf hists browser: Clarify top/report browser help perf mem: Allow all record/report options perf trace: Support MAP_FIXED_NOREPLACE perf: Remove superfluous allocation error check perf: Fix sample_max_stack maximum check perf: Return proper values for user stack errors perf list: Add s390 support for detailed/verbose PMU event description perf script: Extend misc field decoding with switch out event type perf report: Extend raw dump (-D) out with switch out event type perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE] tools/headers: Synchronize kernel ABI headers, v4.17-rc1 trace_kprobe: Remove warning message "Could not insert probe at..." ...
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