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2018-05-13x86/amd_nb: Add support for Raven Ridge CPUsGuenter Roeck1-0/+6
Add Raven Ridge root bridge and data fabric PCI IDs. This is required for amd_pci_dev_to_node_id() and amd_smn_read(). Cc: stable@vger.kernel.org # v4.16+ Tested-by: Gabriel Craciunescu <nix.or.die@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2018-05-13x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores()Thomas Gleixner4-8/+7
No point to have it at the call sites. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-13x86/Centaur: Report correct CPU/cache topologyDavid Wang1-0/+5
Centaur CPUs enumerate the cache topology in the same way as Intel CPUs, but the function is unused so for. The Centaur init code also misses to initialize x86_info::max_cores, so the CPU topology can't be described correctly. Initialize x86_info::max_cores and invoke init_cacheinfo() to make CPU and cache topology information available and correct. Signed-off-by: David Wang <davidwang@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: lukelin@viacpu.com Cc: qiyuanwang@zhaoxin.com Cc: gregkh@linuxfoundation.org Cc: brucechang@via-alliance.com Cc: timguo@zhaoxin.com Cc: cooperyan@zhaoxin.com Cc: hpa@zytor.com Cc: benjaminpan@viatech.com Link: https://lkml.kernel.org/r/1525314766-18910-4-git-send-email-davidwang@zhaoxin.com
2018-05-13x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo()David Wang3-13/+8
There is no point in having the conditional cpu_detect_cache_sizes() call at the callsite of init_intel_cacheinfo(). Move it into init_intel_cacheinfo() and make init_intel_cacheinfo() void. [ tglx: Made the init_intel_cacheinfo() void as the return value was pointless. Adjust changelog accordingly ] Signed-off-by: David Wang <davidwang@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: lukelin@viacpu.com Cc: qiyuanwang@zhaoxin.com Cc: gregkh@linuxfoundation.org Cc: brucechang@via-alliance.com Cc: timguo@zhaoxin.com Cc: cooperyan@zhaoxin.com Cc: hpa@zytor.com Cc: benjaminpan@viatech.com Link: https://lkml.kernel.org/r/1525314766-18910-3-git-send-email-davidwang@zhaoxin.com
2018-05-13x86/build: Remove no-op macro VMLINUX_SYMBOL()Masahiro Yamada1-2/+2
VMLINUX_SYMBOL() is no-op unless CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX is defined. It has ever been selected only by BLACKFIN and METAG. VMLINUX_SYMBOL() is unneeded for x86-specific code. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch <linux-arch@vger.kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: https://lkml.kernel.org/r/1525852174-29022-1-git-send-email-yamada.masahiro@socionext.com
2018-05-13x86/CPU: Make intel_num_cpu_cores() genericDavid Wang3-19/+16
intel_num_cpu_cores() is a static function in intel.c which can't be used by other files. Define another function called detect_num_cpu_cores() in common.c to replace this function so it can be reused. Signed-off-by: David Wang <davidwang@zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: lukelin@viacpu.com Cc: qiyuanwang@zhaoxin.com Cc: gregkh@linuxfoundation.org Cc: brucechang@via-alliance.com Cc: timguo@zhaoxin.com Cc: cooperyan@zhaoxin.com Cc: hpa@zytor.com Cc: benjaminpan@viatech.com Link: https://lkml.kernel.org/r/1525314766-18910-2-git-send-email-davidwang@zhaoxin.com
2018-05-13x86/CPU: Move cpu local function declarations to local headerThomas Gleixner2-0/+11
No point in exposing all these functions globaly as they are strict local to the cpu management code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-12x86/bugs: Fix the parameters alignment and missing voidKonrad Rzeszutek Wilk1-2/+2
Fixes: 7bb4d366c ("x86/bugs: Make cpu_show_common() static") Fixes: 24f7fc83b ("x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation") Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-10x86/bugs: Make cpu_show_common() staticJiri Kosina1-1/+1
cpu_show_common() is not used outside of arch/x86/kernel/cpu/bugs.c, so make it static. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-10x86/bugs: Fix __ssb_select_mitigation() return typeJiri Kosina1-1/+1
__ssb_select_mitigation() returns one of the members of enum ssb_mitigation, not ssb_mitigation_cmd; fix the prototype to reflect that. Fixes: 24f7fc83b9204 ("x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation") Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-09x86/bugs: Rename _RDS to _SSBDKonrad Rzeszutek Wilk5-31/+31
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>
2018-05-09mm/pkeys, x86, powerpc: Display pkey in smaps if arch supports pkeysRam Pai1-8/+0
Currently the architecture specific code is expected to display the protection keys in smap for a given vma. This can lead to redundant code and possibly to divergent formats in which the key gets displayed. This patch changes the implementation. It displays the pkey only if the architecture support pkeys, i.e arch_pkeys_enabled() returns true. x86 arch_show_smap() function is not needed anymore, delete it. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> [mpe: Split out from larger patch, rebased on header changes] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Dave Hansen <dave.hansen@intel.com>
2018-05-08dma-debug: move initialization to common codeChristoph Hellwig1-4/+0
Most mainstream architectures are using 65536 entries, so lets stick to that. If someone is really desperate to override it that can still be done through <asm/dma-mapping.h>, but I'd rather see a really good rationale for that. dma_debug_init is now called as a core_initcall, which for many architectures means much earlier, and provides dma-debug functionality earlier in the boot process. This should be safe as it only relies on the memory allocator already being available. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-05-06Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-1/+5
Pull x86 fix from Thomas Gleixner: "Unbreak the CPUID CPUID_8000_0008_EBX reload which got dropped when the evaluation of physical and virtual bits which uses the same CPUID leaf was moved out of get_cpu_cap()" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Restore CPUID_8000_0008_EBX reload
2018-05-06x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when availableSuravee Suthikulpanit1-1/+10
Derive topology information from Extended Topology Enumeration (CPUID function 0xB) when the information is available. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1524865681-112110-3-git-send-email-suravee.suthikulpanit@amd.com
2018-05-06x86/CPU: Modify detect_extended_topology() to return resultSuravee Suthikulpanit1-4/+4
Current implementation does not communicate whether it can successfully detect CPUID function 0xB information. Therefore, modify the function to return success or error codes. This will be used by subsequent patches. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1524865681-112110-2-git-send-email-suravee.suthikulpanit@amd.com
2018-05-06x86/CPU/AMD: Calculate last level cache ID from number of sharing threadsSuravee Suthikulpanit2-16/+42
Last Level Cache ID can be calculated from the number of threads sharing the cache, which is available from CPUID Fn0x8000001D (Cache Properties). This is used to left-shift the APIC ID to derive LLC ID. Therefore, default to this method unless the APIC ID enumeration does not follow the scheme. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1524864877-111962-5-git-send-email-suravee.suthikulpanit@amd.com
2018-05-06x86/CPU: Rename intel_cacheinfo.c to cacheinfo.cBorislav Petkov2-1/+1
Since this file contains general cache-related information for x86, rename the file to a more generic name. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1524864877-111962-4-git-send-email-suravee.suthikulpanit@amd.com
2018-05-06x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be presentBorislav Petkov3-16/+8
Move smp_num_siblings and cpu_llc_id to cpu/common.c so that they're always present as symbols and not only in the CONFIG_SMP case. Then, other code using them doesn't need ugly ifdeffery anymore. Get rid of some ifdeffery. Signed-off-by: Borislav Petkov <bpetkov@suse.de> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1524864877-111962-2-git-send-email-suravee.suthikulpanit@amd.com
2018-05-06x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read()Luck, Tony1-1/+1
Each of the strings that we want to put into the buf[MAX_FLAG_OPT_SIZE] in flags_read() is two characters long. But the sprintf() adds a trailing newline and will add a terminating NUL byte. So MAX_FLAG_OPT_SIZE needs to be 4. sprintf() calls vsnprintf() and *that* does return: " * The return value is the number of characters which would * be generated for the given input, excluding the trailing * '\0', as per ISO C99." Note the "excluding". Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/20180427163707.ktaiysvbk3yhk4wm@agluck-desk
2018-05-06x86/MCE: Enable MCE broadcasting on new Centaur CPUsDavid Wang1-0/+18
Newer Centaur multi-core CPUs also support MCE broadcasting to all cores. Add a Centaur-specific init function setting that up. [ bp: - make mce_centaur_feature_init() static - flip check to do the f/m/s first for better readability - touch up text ] Signed-off-by: David Wang <davidwang@zhaoxin.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: lukelin@viacpu.com Cc: qiyuanwang@zhaoxin.com Cc: Greg KH <greg@kroah.com> Cc: brucechang@via-alliance.com Cc: timguo@zhaoxin.com Cc: cooperyan@zhaoxin.com Cc: Tony Luck <tony.luck@intel.com> Cc: benjaminpan@viatech.com Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1524652420-17330-2-git-send-email-davidwang@zhaoxin.com
2018-05-05x86/speculation: Make "seccomp" the default mode for Speculative Store BypassKees Cook1-9/+23
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>
2018-05-05seccomp: Move speculation migitation control to arch codeThomas Gleixner1-11/+18
The migitation control is simpler to implement in architecture code as it avoids the extra function call to check the mode. Aside of that having an explicit seccomp enabled mode in the architecture mitigations would require even more workarounds. Move it into architecture code and provide a weak function in the seccomp code. Remove the 'which' argument as this allows the architecture to decide which mitigations are relevant for seccomp. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-05prctl: Add force disable speculationThomas Gleixner1-10/+25
For certain use cases it is desired to enforce mitigations so they cannot be undone afterwards. That's important for loader stubs which want to prevent a child from disabling the mitigation again. Will also be used for seccomp(). The extra state preserving of the prctl state for SSB is a preparatory step for EBPF dymanic speculation control. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-05x86/bugs: Make boot modes __ro_after_initKees Cook1-2/+3
There's no reason for these to be changed after boot. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-03nospec: Allow getting/setting on non-current taskKees Cook1-11/+16
Adjust arch_prctl_get/set_spec_ctrl() to operate on tasks other than current. This is needed both for /proc/$pid/status queries and for seccomp (since thread-syncing can trigger seccomp in non-current threads). Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-03x86/speculation: Add prctl for Speculative Store Bypass mitigationThomas Gleixner1-10/+73
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>
2018-05-03x86/process: Allow runtime control of Speculative Store BypassThomas Gleixner2-5/+43
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>
2018-05-03x86/speculation: Create spec-ctrl.h to avoid include hellThomas Gleixner2-2/+2
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>
2018-05-03x86/bugs/AMD: Add support to disable RDS on Fam[15,16,17]h if requestedKonrad Rzeszutek Wilk3-1/+56
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>
2018-05-03x86/bugs: Whitelist allowed SPEC_CTRL MSR valuesKonrad Rzeszutek Wilk1-2/+9
Intel and AMD SPEC_CTRL (0x48) MSR semantics may differ in the future (or in fact use different MSRs for the same functionality). As such a run-time mechanism is required to whitelist the appropriate MSR values. [ tglx: Made the variable __ro_after_init ] 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>
2018-05-03x86/bugs/intel: Set proper CPU features and setup RDSKonrad Rzeszutek Wilk4-6/+37
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>
2018-05-03x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigationKonrad Rzeszutek Wilk1-0/+103
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>
2018-05-03x86/bugs: Expose /sys/../spec_store_bypassKonrad Rzeszutek Wilk2-0/+28
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>
2018-05-03x86/bugs, KVM: Support the combination of guest and host IBRSKonrad Rzeszutek Wilk1-0/+18
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>
2018-05-03x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bitsKonrad Rzeszutek Wilk1-0/+28
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>
2018-05-03x86/bugs: Concentrate bug reporting into a separate functionKonrad Rzeszutek Wilk1-14/+32
Those SysFS functions have a similar preamble, as such make common code to handle them. 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: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03x86/bugs: Concentrate bug detection into a separate functionKonrad Rzeszutek Wilk1-10/+11
Combine the various logic which goes through all those x86_cpu_id matching structures in one function. 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: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-02x86/cpu: Restore CPUID_8000_0008_EBX reloadThomas Gleixner1-1/+5
The recent commt which addresses the x86_phys_bits corruption with encrypted memory on CPUID reload after a microcode update lost the reload of CPUID_8000_0008_EBX as well. As a consequence IBRS and IBRS_FW are not longer detected Restore the behaviour by bringing the reload of CPUID_8000_0008_EBX back. This restore has a twist due to the convoluted way the cpuid analysis works: CPUID_8000_0008_EBX is used by AMD to enumerate IBRB, IBRS, STIBP. On Intel EBX is not used. But the speculation control code sets the AMD bits when running on Intel depending on the Intel specific speculation control bits. This was done to use the same bits for alternatives. The change which moved the 8000_0008 evaluation out of get_cpu_cap() broke this nasty scheme due to ordering. So that on Intel the store to CPUID_8000_0008_EBX clears the IBRB, IBRS, STIBP bits which had been set before by software. So the actual CPUID_8000_0008_EBX needs to go back to the place where it was and the phys/virt address space calculation cannot touch it. In hindsight this should have used completely synthetic bits for IBRB, IBRS, STIBP instead of reusing the AMD bits, but that's for 4.18. /me needs to find time to cleanup that steaming pile of ... Fixes: d94a155c59c9 ("x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption") Reported-by: Jörg Otte <jrg.otte@gmail.com> Reported-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Jörg Otte <jrg.otte@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: kirill.shutemov@linux.intel.com Cc: Borislav Petkov <bp@alien8.de Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1805021043510.1668@nanos.tec.linutronix.de
2018-05-02Merge branch 'timers/urgent' into timers/coreThomas Gleixner10-117/+72
Pick up urgent fixes to apply dependent cleanup patch
2018-05-02x86/tsc: Fix mark_tsc_unstable()Peter Zijlstra1-7/+5
mark_tsc_unstable() also needs to affect tsc_early, Now that clocksource_mark_unstable() can be used on a clocksource irrespective of its registration state, use it on both tsc_early and tsc. This does however require cs->list to be initialized empty, otherwise it cannot tell the registation state before registation. Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Diego Viola <diego.viola@gmail.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.533326547@infradead.org
2018-05-02x86/tsc: Always unregister clocksource_tsc_earlyPeter Zijlstra1-4/+6
Don't leave the tsc-early clocksource registered if it errors out early. This was reported by Diego, who on his Core2 era machine got TSC invalidated while it was running with tsc-early (due to C-states). This results in keeping tsc-early with very bad effects. Reported-and-Tested-by: Diego Viola <diego.viola@gmail.com> Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.350507853@infradead.org
2018-04-27x86/setup: Do not reserve a crash kernel region if booted on Xen PVPetr Tesarik1-0/+6
Xen PV domains cannot shut down and start a crash kernel. Instead, the crashing kernel makes a SCHEDOP_shutdown hypercall with the reason code SHUTDOWN_crash, cf. xen_crash_shutdown() machine op in arch/x86/xen/enlighten_pv.c. A crash kernel reservation is merely a waste of RAM in this case. It may also confuse users of kexec_load(2) and/or kexec_file_load(2). When flags include KEXEC_ON_CRASH or KEXEC_FILE_ON_CRASH, respectively, these syscalls return success, which is technically correct, but the crash kexec image will never be actually used. Signed-off-by: Petr Tesarik <ptesarik@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: xen-devel@lists.xenproject.org Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@suse.de> Cc: Jean Delvare <jdelvare@suse.de> Link: https://lkml.kernel.org/r/20180425120835.23cef60c@ezekiel.suse.cz
2018-04-27x86/i8237: Register device based on FADT legacy boot flagRajneesh Bhardwaj2-1/+31
From Skylake onwards, the platform controller hub (Sunrisepoint PCH) does not support legacy DMA operations to IO ports 81h-83h, 87h, 89h-8Bh, 8Fh. Currently this driver registers as syscore ops and its resume function is called on every resume from S3. On Skylake and Kabylake, this causes a resume delay of around 100ms due to port IO operations, which is a problem. This change allows to load the driver only when the platform bios explicitly supports such devices or has a cut-off date earlier than 2017 due to the following reasons: - The platforms released before year 2017 have support for the 8237. (except Sunrisepoint PCH e.g. Skylake) - Some of the BIOS that were released for platforms (Skylake, Kabylake) during 2016-17 are buggy. These BIOS do not set/unset the ACPI_FADT_LEGACY_DEVICES field in FADT table properly based on the presence or absence of the DMA device. Very recently, open source system firmware like coreboot started unsetting ACPI_FADT_LEGACY_DEVICES field in FADT table if the 8237 DMA device is not present on the PCH. Please refer to chapter 21 of 6th Generation Intel® Core™ Processor Platform Controller Hub Family: BIOS Specification. Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: rjw@rjwysocki.net Cc: hpa@zytor.com Cc: Alan Cox <alan@linux.intel.com> Link: https://lkml.kernel.org/r/1522336015-22994-1-git-send-email-anshuman.gupta@intel.com
2018-04-26x86/cpu/intel: Add missing TLB cpuid valuesjacek.tomaka@poczta.fm1-0/+3
Make kernel print the correct number of TLB entries on Intel Xeon Phi 7210 (and others) Before: [ 0.320005] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0 After: [ 0.320005] Last level dTLB entries: 4KB 256, 2MB 128, 4MB 128, 1GB 16 The entries do exist in the official Intel SMD but the type column there is incorrect (states "Cache" where it should read "TLB"), but the entries for the values 0x6B, 0x6C and 0x6D are correctly described as 'Data TLB'. Signed-off-by: Jacek Tomaka <jacek.tomaka@poczta.fm> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180423161425.24366-1-jacekt@dugeo.com
2018-04-26x86/dumpstack: Explain the reasoning for the prologue and buffer sizeBorislav Petkov1-0/+19
The whole reasoning behind the amount of opcode bytes dumped and prologue length isn't very clear so write down some of the reasons for why it is done the way it is. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Link: https://lkml.kernel.org/r/20180417161124.5294-10-bp@alien8.de
2018-04-26x86/dumpstack: Save first regs set for the executive summaryBorislav Petkov1-20/+12
Save the regs set when __die() is onvoked for the first time and print it in oops_end(). Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Link: https://lkml.kernel.org/r/20180417161124.5294-9-bp@alien8.de
2018-04-26x86/dumpstack: Add a show_ip() functionBorislav Petkov2-15/+16
... which shows the Instruction Pointer along with the insn bytes around it. Use it whenever rIP is printed. Drop the rIP < PAGE_OFFSET check since probe_kernel_read() can handle any address properly. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Link: https://lkml.kernel.org/r/20180417161124.5294-8-bp@alien8.de
2018-04-26x86/dumpstack: Add loglevel argument to show_opcodes()Borislav Petkov1-3/+3
Will be used in the next patch. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Link: https://lkml.kernel.org/r/20180417161124.5294-6-bp@alien8.de
2018-04-26x86/dumpstack: Improve opcodes dumping in the code sectionBorislav Petkov1-16/+15
The code used to iterate byte-by-byte over the bytes around RIP and that is expensive: disabling pagefaults around it, copy_from_user, etc... Make it read the whole buffer of OPCODE_BUFSIZE size in one go. Use a statically allocated 64 bytes buffer so that concurrent show_opcodes() do not interleave in the output even though in the majority of the cases it's serialized via die_lock. Except the #PF path which doesn't... Also, do the PAGE_OFFSET check outside of the function because latter will be reused in other context. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Link: https://lkml.kernel.org/r/20180417161124.5294-5-bp@alien8.de