1. 15 Nov, 2019 12 commits
  2. 14 Nov, 2019 9 commits
    • Xiaojie Yuan's avatar
      drm/amdgpu: fix null pointer deref in firmware header printing · a84fddb1
      Xiaojie Yuan authored
      v2: declare as (struct common_firmware_header *) type because
          struct xxx_firmware_header inherits from it
      When CE's ucode_id(8) is used to get sdma_hdr, we will be accessing an
      unallocated amdgpu_firmware_info instance.
      This issue appears on rhel7.7 with gcc 4.8.5. Newer compilers might have
      optimized out such 'defined but not referenced' variable.
      [ 1120.798564] BUG: unable to handle kernel NULL pointer dereference at 000000000000000a
      [ 1120.806703] IP: [<ffffffffc0e3c9b3>] psp_np_fw_load+0x1e3/0x390 [amdgpu]
      [ 1120.813693] PGD 80000002603ff067 PUD 271b8d067 PMD 0
      [ 1120.818931] Oops: 0000 [#1] SMP
      [ 1120.822245] Modules linked in: amdgpu(OE+) amdkcl(OE) amd_iommu_v2 amdttm(OE) amd_sched(OE) xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun bridge stp llc devlink ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat iptable_mangle iptable_security iptable_raw nf_conntrack libcrc32c ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter sunrpc dm_mirror dm_region_hash dm_log dm_mod intel_pmc_core intel_powerclamp coretemp intel_rapl joydev kvm_intel eeepc_wmi asus_wmi kvm sparse_keymap iTCO_wdt irqbypass rfkill crc32_pclmul snd_hda_codec_realtek mxm_wmi ghash_clmulni_intel intel_wmi_thunderbolt iTCO_vendor_support snd_hda_codec_generic snd_hda_codec_hdmi aesni_intel lrw gf128mul glue_helper ablk_helper sg cryptd pcspkr snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd pinctrl_sunrisepoint pinctrl_intel soundcore acpi_pad mei_me wmi mei i2c_i801 pcc_cpufreq ip_tables ext4 mbcache jbd2 sd_mod crc_t10dif crct10dif_generic i915 i2c_algo_bit iosf_mbi drm_kms_helper e1000e syscopyarea sysfillrect sysimgblt fb_sys_fops ahci libahci drm ptp libata crct10dif_pclmul crct10dif_common crc32c_intel serio_raw pps_core drm_panel_orientation_quirks video i2c_hid
      [ 1120.954136] CPU: 4 PID: 2426 Comm: modprobe Tainted: G           OE  ------------   3.10.0-1062.el7.x86_64 #1
      [ 1120.964390] Hardware name: System manufacturer System Product Name/Z170-A, BIOS 1302 11/09/2015
      [ 1120.973321] task: ffff991ef1e3c1c0 ti: ffff991ee625c000 task.ti: ffff991ee625c000
      [ 1120.981020] RIP: 0010:[<ffffffffc0e3c9b3>]  [<ffffffffc0e3c9b3>] psp_np_fw_load+0x1e3/0x390 [amdgpu]
      [ 1120.990483] RSP: 0018:ffff991ee625f950  EFLAGS: 00010202
      [ 1120.995935] RAX: 0000000000000002 RBX: ffff991edf6b2d38 RCX: ffff991edf6a0000
      [ 1121.003391] RDX: 0000000000000000 RSI: ffff991f01d13898 RDI: ffffffffc110afb3
      [ 1121.010706] RBP: ffff991ee625f9b0 R08: 0000000000000000 R09: 0000000000000000
      [ 1121.018029] R10: 00000000000004c4 R11: ffff991ee625f64e R12: ffff991edf6b3220
      [ 1121.025353] R13: ffff991edf6a0000 R14: 0000000000000008 R15: ffff991edf6b2d30
      [ 1121.032666] FS:  00007f97b0c0b740(0000) GS:ffff991f01d00000(0000) knlGS:0000000000000000
      [ 1121.041000] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [ 1121.046880] CR2: 000000000000000a CR3: 000000025e604000 CR4: 00000000003607e0
      [ 1121.054239] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
      [ 1121.061631] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
      [ 1121.068938] Call Trace:
      [ 1121.071494]  [<ffffffffc0e3dba8>] psp_hw_init+0x218/0x270 [amdgpu]
      [ 1121.077886]  [<ffffffffc0da3188>] amdgpu_device_fw_loading+0xe8/0x160 [amdgpu]
      [ 1121.085296]  [<ffffffffc0e3b34c>] ? vega10_ih_irq_init+0x4bc/0x730 [amdgpu]
      [ 1121.092534]  [<ffffffffc0da5c75>] amdgpu_device_init+0x1495/0x1c90 [amdgpu]
      [ 1121.099675]  [<ffffffffc0da9cab>] amdgpu_driver_load_kms+0x8b/0x2f0 [amdgpu]
      [ 1121.106888]  [<ffffffffc01b25cf>] drm_dev_register+0x12f/0x1d0 [drm]
      [ 1121.113419]  [<ffffffffa4dcdfd8>] ? pci_enable_device_flags+0xe8/0x140
      [ 1121.120183]  [<ffffffffc0da260a>] amdgpu_pci_probe+0xca/0x170 [amdgpu]
      [ 1121.126919]  [<ffffffffa4dcf97a>] local_pci_probe+0x4a/0xb0
      [ 1121.132622]  [<ffffffffa4dd10c9>] pci_device_probe+0x109/0x160
      [ 1121.138607]  [<ffffffffa4eb4205>] driver_probe_device+0xc5/0x3e0
      [ 1121.144766]  [<ffffffffa4eb4603>] __driver_attach+0x93/0xa0
      [ 1121.150507]  [<ffffffffa4eb4570>] ? __device_attach+0x50/0x50
      [ 1121.156422]  [<ffffffffa4eb1da5>] bus_for_each_dev+0x75/0xc0
      [ 1121.162213]  [<ffffffffa4eb3b7e>] driver_attach+0x1e/0x20
      [ 1121.167771]  [<ffffffffa4eb3620>] bus_add_driver+0x200/0x2d0
      [ 1121.173590]  [<ffffffffa4eb4c94>] driver_register+0x64/0xf0
      [ 1121.179345]  [<ffffffffa4dd0905>] __pci_register_driver+0xa5/0xc0
      [ 1121.185593]  [<ffffffffc099f000>] ? 0xffffffffc099efff
      [ 1121.190914]  [<ffffffffc099f0a4>] amdgpu_init+0xa4/0xb0 [amdgpu]
      [ 1121.197101]  [<ffffffffa4a0210a>] do_one_initcall+0xba/0x240
      [ 1121.202901]  [<ffffffffa4b1c90a>] load_module+0x271a/0x2bb0
      [ 1121.208598]  [<ffffffffa4dad740>] ? ddebug_proc_write+0x100/0x100
      [ 1121.214894]  [<ffffffffa4b1ce8f>] SyS_init_module+0xef/0x140
      [ 1121.220698]  [<ffffffffa518bede>] system_call_fastpath+0x25/0x2a
      [ 1121.226870] Code: b4 01 60 a2 00 00 31 c0 e8 83 60 33 e4 41 8b 47 08 48 8b 4d d0 48 c7 c7 b3 af 10 c1 48 69 c0 68 07 00 00 48 8b 84 01 60 a2 00 00 <48> 8b 70 08 31 c0 48 89 75 c8 e8 56 60 33 e4 48 8b 4d d0 48 c7
      [ 1121.247422] RIP  [<ffffffffc0e3c9b3>] psp_np_fw_load+0x1e3/0x390 [amdgpu]
      [ 1121.254432]  RSP <ffff991ee625f950>
      [ 1121.258017] CR2: 000000000000000a
      [ 1121.261427] ---[ end trace e98b35387ede75bd ]---
      Signed-off-by: default avatarXiaojie Yuan <xiaojie.yuan@amd.com>
      Fixes: c5fb9126
       ("drm/amdgpu: add firmware header printing for psp fw loading (v2)")
      Reviewed-by: default avatarKevin Wang <kevin1.wang@amd.com>
      Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
    • Takashi Iwai's avatar
      ALSA: usb-audio: Fix incorrect size check for processing/extension units · 976a68f0
      Takashi Iwai authored
      The recently introduced unit descriptor validation had some bug for
      processing and extension units, it counts a bControlSize byte twice so
      it expected a bigger size than it should have been.  This seems
      resulting in a probe error on a few devices.
      Fix the calculation for proper checks of PU and EU.
      Fixes: 57f87706 ("ALSA: usb-audio: More validations of descriptor units")
      Cc: <stable@vger.kernel.org>
      Link: https://lore.kernel.org/r/20191114165613.7422-1-tiwai@suse.de
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    • Linus Torvalds's avatar
      Merge tag 'kbuild-fixes-v5.4-3' of... · 96b95eff
      Linus Torvalds authored
      Merge tag 'kbuild-fixes-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
      Pull Kbuild fixes from Masahiro Yamada:
       - fix build error when compiling SPARC VDSO with CONFIG_COMPAT=y
       - pass correct --arch option to Sparse
      * tag 'kbuild-fixes-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
        kbuild: tell sparse about the $ARCH
        sparc: vdso: fix build error of vdso32
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma · 4e84608c
      Linus Torvalds authored
      Pull RDMA fixes from Jason Gunthorpe:
       "Bug fixes for old bugs in the hns and hfi1 drivers:
         - Calculate various values in hns properly to avoid over/underflows
           in some cases
         - Fix an oops, PCI negotiation on Gen4 systems, and bugs related to
      * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
        RDMA/hns: Correct the value of srq_desc_size
        RDMA/hns: Correct the value of HNS_ROCE_HEM_CHUNK_LEN
        IB/hfi1: TID RDMA WRITE should not return IB_WC_RNR_RETRY_EXC_ERR
        IB/hfi1: Calculate flow weight based on QP MTU for TID RDMA
        IB/hfi1: Ensure r_tid_ack is valid before building TID RDMA ACK packet
        IB/hfi1: Ensure full Gen3 speed in a Gen4 system
    • Sean Christopherson's avatar
      KVM: x86/mmu: Take slots_lock when using kvm_mmu_zap_all_fast() · ed69a6cb
      Sean Christopherson authored
      Acquire the per-VM slots_lock when zapping all shadow pages as part of
      toggling nx_huge_pages.  The fast zap algorithm relies on exclusivity
      (via slots_lock) to identify obsolete vs. valid shadow pages, because it
      uses a single bit for its generation number. Holding slots_lock also
      obviates the need to acquire a read lock on the VM's srcu.
      Failing to take slots_lock when toggling nx_huge_pages allows multiple
      instances of kvm_mmu_zap_all_fast() to run concurrently, as the other
      user, KVM_SET_USER_MEMORY_REGION, does not take the global kvm_lock.
      (kvm_mmu_zap_all_fast() does take kvm->mmu_lock, but it can be
      temporarily dropped by kvm_zap_obsolete_pages(), so it is not enough
      to enforce exclusivity).
      Concurrent fast zap instances causes obsolete shadow pages to be
      incorrectly identified as valid due to the single bit generation number
      wrapping, which results in stale shadow pages being left in KVM's MMU
      and leads to all sorts of undesirable behavior.
      The bug is easily confirmed by running with CONFIG_PROVE_LOCKING and
      toggling nx_huge_pages via its module param.
      Note, until commit 4ae5acbc4936 ("KVM: x86/mmu: Take slots_lock when
      using kvm_mmu_zap_all_fast()", 2019-11-13) the fast zap algorithm used
      an ulong-sized generation instead of relying on exclusivity for
      correctness, but all callers except the recently added set_nx_huge_pages()
      needed to hold slots_lock anyways.  Therefore, this patch does not have
      to be backported to stable kernels.
      Given that toggling nx_huge_pages is by no means a fast path, force it
      to conform to the current approach instead of reintroducing the previous
      generation count.
      Fixes: b8e8c830
       ("kvm: mmu: ITLB_MULTIHIT mitigation", but NOT FOR STABLE)
      Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    • Luc Van Oostenryck's avatar
      kbuild: tell sparse about the $ARCH · 80591e61
      Luc Van Oostenryck authored
      Sparse uses the same executable for all archs and uses flags
      like -m64, -mbig-endian or -D__arm__ for arch-specific parameters.
      But Sparse also uses value from the host machine used to build
      Sparse as default value for the target machine.
      This works, of course, well for native build but can create
      problems when cross-compiling, like defining both '__i386__'
      and '__arm__' when cross-compiling for arm on a x86-64 machine.
      Fix this by explicitely telling sparse the target architecture.
      Reported-by: default avatarBen Dooks <ben.dooks@codethink.co.uk>
      Signed-off-by: default avatarLuc Van Oostenryck <luc.vanoostenryck@gmail.com>
      Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
    • Masahiro Yamada's avatar
      sparc: vdso: fix build error of vdso32 · 53472914
      Masahiro Yamada authored
      Since commit 54b8ae66 ("kbuild: change *FLAGS_<basetarget>.o to
      take the path relative to $(obj)"), sparc allmodconfig fails to build
      as follows:
        CC      arch/sparc/vdso/vdso32/vclock_gettime.o
      unrecognized e_machine 18 arch/sparc/vdso/vdso32/vclock_gettime.o
      arch/sparc/vdso/vdso32/vclock_gettime.o: failed
      The cause of the breakage is that -pg flag not being dropped.
      The vdso32 files are located in the vdso32/ subdirectory, but I missed
      to update the Makefile.
      I removed the meaningless CFLAGS_REMOVE_vdso-note.o since it is only
      effective for C file.
      vdso-note.o is compiled from assembly file:
      Fixes: 54b8ae66
       ("kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)")
      Reported-by: default avatarAnatoly Pugachev <matorola@gmail.com>
      Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      Tested-by: default avatarAnatoly Pugachev <matorola@gmail.com>
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
    • Eugen Hristev's avatar
      mmc: sdhci-of-at91: fix quirk2 overwrite · fed23c58
      Eugen Hristev authored
      The quirks2 are parsed and set (e.g. from DT) before the quirk for broken
      HS200 is set in the driver.
      The driver needs to enable just this flag, not rewrite the whole quirk set.
      Fixes: 7871aa60
       ("mmc: sdhci-of-at91: add quirk for broken HS200")
      Signed-off-by: default avatarEugen Hristev <eugen.hristev@microchip.com>
      Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    • Takashi Iwai's avatar
      ALSA: usb-audio: Fix incorrect NULL check in create_yamaha_midi_quirk() · cc9dbfa9
      Takashi Iwai authored
      The commit 60849562 ("ALSA: usb-audio: Fix possible NULL
      dereference at create_yamaha_midi_quirk()") added NULL checks in
      create_yamaha_midi_quirk(), but there was an overlook.  The code
      allows one of either injd or outjd is NULL, but the second if check
      made returning -ENODEV if any of them is NULL.  Fix it in a proper
      Fixes: 60849562
       ("ALSA: usb-audio: Fix possible NULL dereference at create_yamaha_midi_quirk()")
      Reported-by: default avatarPavel Machek <pavel@denx.de>
      Cc: <stable@vger.kernel.org>
      Link: https://lore.kernel.org/r/20191113111259.24123-1-tiwai@suse.de
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
  3. 13 Nov, 2019 14 commits
  4. 12 Nov, 2019 5 commits
    • Linus Torvalds's avatar
      Remove VirtualBox guest shared folders filesystem · 0e3f1ad8
      Linus Torvalds authored
      This went into staging in rc7.  It turns out that was a mistake, and
      apparently it wasn't even supposed to go there at all, but be introduced
      as a regular filesystem.
      We don't try to sneak in whole new filesystems this late in the rc, just
      delete the whole thing, and it can be re-introduced as a proper patch
      with proper acks from actual filesystem people instead of some odd
      late-rc staging back-door.
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Hans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 8c5bd25b
      Linus Torvalds authored
      Pull kvm fixes from Paolo Bonzini:
       "Fix unwinding of KVM_CREATE_VM failure, VT-d posted interrupts,
        DAX/ZONE_DEVICE, and module unload/reload"
      * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
        KVM: MMU: Do not treat ZONE_DEVICE pages as being reserved
        KVM: VMX: Introduce pi_is_pir_empty() helper
        KVM: VMX: Do not change PID.NDST when loading a blocked vCPU
        KVM: VMX: Consider PID.PIR to determine if vCPU has pending interrupts
        KVM: VMX: Fix comment to specify PID.ON instead of PIR.ON
        KVM: X86: Fix initialization of MSR lists
        KVM: fix placement of refcount initialization
        KVM: Fix NULL-ptr deref after kvm_create_vm fails
    • Rodrigo Vivi's avatar
      Merge tag 'gvt-fixes-2019-11-12' of https://github.com/intel/gvt-linux into drm-intel-fixes · 31e8d629
      Rodrigo Vivi authored
      - Fix dmabuf reference drop (Pan)
      Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
      From: Zhenyu Wang <zhenyuw@linux.intel.com>
      Link: https://patchwork.freedesktop.org/patch/msgid/20191112061834.GN4196@zhen-hp.sh.intel.com
    • Jani Nikula's avatar
      drm/i915: update rawclk also on resume · 2f216a85
      Jani Nikula authored
      Since CNP it's possible for rawclk to have two different values, 19.2
      and 24 MHz. If the value indicated by SFUSE_STRAP register is different
      from the power on default for PCH_RAWCLK_FREQ, we'll end up having a
      mismatch between the rawclk hardware and software states after
      suspend/resume. On previous platforms this used to work by accident,
      because the power on defaults worked just fine.
      Update the rawclk also on resume. The natural place to do this would be
      intel_modeset_init_hw(), however VLV/CHV need it done before
      intel_power_domains_init_hw(). Thus put it there even if it feels
      slightly out of place.
      v2: Call intel_update_rawclck() in intel_power_domains_init_hw() for all
          platforms (Ville).
      Reported-by: default avatarShawn Lee <shawn.c.lee@intel.com>
      Cc: Shawn Lee <shawn.c.lee@intel.com>
      Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
      Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Tested-by: default avatarShawn Lee <shawn.c.lee@intel.com>
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      Link: https://patchwork.freedesktop.org/patch/msgid/20191101142024.13877-1-jani.nikula@intel.com
      (cherry picked from commit 59ed05cc
      Cc: <stable@vger.kernel.org> # v4.15+
      Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
    • Linus Torvalds's avatar
      Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · eb094f06
      Linus Torvalds authored
      Pull x86 TSX Async Abort and iTLB Multihit mitigations from Thomas Gleixner:
       "The performance deterioration departement is not proud at all of
        presenting the seventh installment of speculation mitigations and
        hardware misfeature workarounds:
         1) TSX Async Abort (TAA) - 'The Annoying Affair'
            TAA is a hardware vulnerability that allows unprivileged
            speculative access to data which is available in various CPU
            internal buffers by using asynchronous aborts within an Intel TSX
            transactional region.
            The mitigation depends on a microcode update providing a new MSR
            which allows to disable TSX in the CPU. CPUs which have no
            microcode update can be mitigated by disabling TSX in the BIOS if
            the BIOS provides a tunable.
            Newer CPUs will have a bit set which indicates that the CPU is not
            vulnerable, but the MSR to disable TSX will be available
            nevertheless as it is an architected MSR. That means the kernel
            provides the ability to disable TSX on the kernel command line,
            which is useful as TSX is a truly useful mechanism to accelerate
            side channel attacks of all sorts.
         2) iITLB Multihit (NX) - 'No eXcuses'
            iTLB Multihit is an erratum where some Intel processors may incur
            a machine check error, possibly resulting in an unrecoverable CPU
            lockup, when an instruction fetch hits multiple entries in the
            instruction TLB. This can occur when the page size is changed
            along with either the physical address or cache type. A malicious
            guest running on a virtualized system can exploit this erratum to
            perform a denial of service attack.
            The workaround is that KVM marks huge pages in the extended page
            tables as not executable (NX). If the guest attempts to execute in
            such a page, the page is broken down into 4k pages which are
            marked executable. The workaround comes with a mechanism to
            recover these shattered huge pages over time.
        Both issues come with full documentation in the hardware
        vulnerabilities section of the Linux kernel user's and administrator's
        Thanks to all patch authors and reviewers who had the extraordinary
        priviledge to be exposed to this nuisance.
        Special thanks to Borislav Petkov for polishing the final TAA patch
        set and to Paolo Bonzini for shepherding the KVM iTLB workarounds and
        providing also the backports to stable kernels for those!"
      * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs
        Documentation: Add ITLB_MULTIHIT documentation
        kvm: x86: mmu: Recovery of shattered NX large pages
        kvm: Add helper function for creating VM worker threads
        kvm: mmu: ITLB_MULTIHIT mitigation
        cpu/speculation: Uninline and export CPU mitigations helpers
        x86/cpu: Add Tremont to the cpu vulnerability whitelist
        x86/bugs: Add ITLB_MULTIHIT bug infrastructure
        x86/tsx: Add config options to set tsx=on|off|auto
        x86/speculation/taa: Add documentation for TSX Async Abort
        x86/tsx: Add "auto" option to the tsx= cmdline parameter
        kvm/x86: Export MDS_NO=0 to guests when TSX is enabled
        x86/speculation/taa: Add sysfs reporting for TSX Async Abort
        x86/speculation/taa: Add mitigation for TSX Async Abort
        x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default
        x86/cpu: Add a helper function x86_read_arch_cap_msr()
        x86/msr: Add the IA32_TSX_CTRL MSR