<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux/tools/arch, branch v5.10</title>
<subtitle>Mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/
</subtitle>
<id>https://git.shady.money/linux/atom?h=v5.10</id>
<link rel='self' href='https://git.shady.money/linux/atom?h=v5.10'/>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/'/>
<updated>2020-12-06T08:58:13Z</updated>
<entry>
<title>x86/uprobes: Do not use prefixes.nbytes when looping over prefixes.bytes</title>
<updated>2020-12-06T08:58:13Z</updated>
<author>
<name>Masami Hiramatsu</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2020-12-03T04:50:37Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=4e9a5ae8df5b3365183150f6df49e49dece80d8c'/>
<id>urn:sha1:4e9a5ae8df5b3365183150f6df49e49dece80d8c</id>
<content type='text'>
Since insn.prefixes.nbytes can be bigger than the size of
insn.prefixes.bytes[] when a prefix is repeated, the proper check must
be

  insn.prefixes.bytes[i] != 0 and i &lt; 4

instead of using insn.prefixes.nbytes.

Introduce a for_each_insn_prefix() macro for this purpose. Debugged by
Kees Cook &lt;keescook@chromium.org&gt;.

 [ bp: Massage commit message, sync with the respective header in tools/
   and drop "we". ]

Fixes: 2b1444983508 ("uprobes, mm, x86: Add the ability to install and remove uprobes breakpoints")
Reported-by: syzbot+9b64b619f10f19d19a7c@syzkaller.appspotmail.com
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Srikar Dronamraju &lt;srikar@linux.vnet.ibm.com&gt;
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/160697103739.3146288.7437620795200799020.stgit@devnote2
</content>
</entry>
<entry>
<title>tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'</title>
<updated>2020-11-12T20:55:41Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-11-09T16:59:15Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=db1a8b97a0a36155171dbb805fbcb276e07559f6'/>
<id>urn:sha1:db1a8b97a0a36155171dbb805fbcb276e07559f6</id>
<content type='text'>
To bring in the change made in this cset:

  4d6ffa27b8e5116c ("x86/lib: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S")
  6dcc5627f6aec4cb ("x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_*")

I needed to define SYM_FUNC_START_LOCAL() as SYM_L_GLOBAL as
mem{cpy,set}_{orig,erms} are used by 'perf bench'.

This silences these perf tools build warnings:

  Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
  diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
  Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S'
  diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Fangrui Song &lt;maskray@google.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools kvm headers: Update KVM headers from the kernel sources</title>
<updated>2020-11-03T11:46:30Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-10-19T16:42:55Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=aa04899a13078e4181146212555a1bbaa387d2c9'/>
<id>urn:sha1:aa04899a13078e4181146212555a1bbaa387d2c9</id>
<content type='text'>
Some should cause changes in tooling, like the one adding LAST_EXCP, but
the way it is structured end up not making that happen.

The new SVM_EXIT_INVPCID should get used by arch/x86/util/kvm-stat.c,
in the svm_exit_reasons table.

The tools/perf/trace/beauty part has scripts to catch changes and
automagically create tables, like tools/perf/trace/beauty/kvm_ioctl.sh,
but changes are needed to make tools/perf/arch/x86/util/kvm-stat.c catch
those automatically.

These were handled by the existing scripts:

  $ tools/perf/trace/beauty/kvm_ioctl.sh &gt; before
  $ cp include/uapi/linux/kvm.h tools/include/uapi/linux/kvm.h
  $ tools/perf/trace/beauty/kvm_ioctl.sh &gt; after
  $ diff -u before after
  --- before	2020-11-03 08:43:52.910728608 -0300
  +++ after	2020-11-03 08:44:04.273959984 -0300
  @@ -89,6 +89,7 @@
   	[0xbf] = "SET_NESTED_STATE",
   	[0xc0] = "CLEAR_DIRTY_LOG",
   	[0xc1] = "GET_SUPPORTED_HV_CPUID",
  +	[0xc6] = "X86_SET_MSR_FILTER",
   	[0xe0] = "CREATE_DEVICE",
   	[0xe1] = "SET_DEVICE_ATTR",
   	[0xe2] = "GET_DEVICE_ATTR",
  $
  $ tools/perf/trace/beauty/vhost_virtio_ioctl.sh &gt; before
  $ cp include/uapi/linux/vhost.h tools/include/uapi/linux/vhost.h
  $
  $ tools/perf/trace/beauty/vhost_virtio_ioctl.sh &gt; after
  $ diff -u before after
  --- before	2020-11-03 08:45:55.522225198 -0300
  +++ after	2020-11-03 08:46:12.881578666 -0300
  @@ -37,4 +37,5 @@
   	[0x71] = "VDPA_GET_STATUS",
   	[0x73] = "VDPA_GET_CONFIG",
   	[0x76] = "VDPA_GET_VRING_NUM",
  +	[0x78] = "VDPA_GET_IOVA_RANGE",
   };
  $

This addresses these perf build warnings:

  Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/kvm.h' differs from latest version at 'arch/arm64/include/uapi/asm/kvm.h'
  diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h
  Warning: Kernel ABI header at 'tools/arch/s390/include/uapi/asm/sie.h' differs from latest version at 'arch/s390/include/uapi/asm/sie.h'
  diff -u tools/arch/s390/include/uapi/asm/sie.h arch/s390/include/uapi/asm/sie.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/kvm.h' differs from latest version at 'arch/x86/include/uapi/asm/kvm.h'
  diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/svm.h' differs from latest version at 'arch/x86/include/uapi/asm/svm.h'
  diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h
  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
  diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
  Warning: Kernel ABI header at 'tools/include/uapi/linux/vhost.h' differs from latest version at 'include/uapi/linux/vhost.h'
  diff -u tools/include/uapi/linux/vhost.h include/uapi/linux/vhost.h

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexander Yarygin &lt;yarygin@linux.vnet.ibm.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Cc: Cornelia Huck &lt;cornelia.huck@de.ibm.com&gt;
Cc: David Ahern &lt;dsahern@gmail.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joerg Roedel &lt;jroedel@suse.de&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools arch x86: Sync the msr-index.h copy with the kernel sources</title>
<updated>2020-11-03T11:36:30Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-10-19T16:28:04Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=32b734e09ec38a0bb81d05d37056a95584d14c99'/>
<id>urn:sha1:32b734e09ec38a0bb81d05d37056a95584d14c99</id>
<content type='text'>
To pick up the changes in:

  29dcc60f6a19fb0a ("x86/boot/compressed/64: Add stage1 #VC handler")
  36e1be8ada994d50 ("perf/x86/amd/ibs: Fix raw sample data accumulation")
  59a854e2f3b90ad2 ("perf/x86/intel: Support TopDown metrics on Ice Lake")
  7b2c05a15d29d057 ("perf/x86/intel: Generic support for hardware TopDown metrics")
  99e40204e014e066 ("x86/msr: Move the F15h MSRs where they belong")
  b57de6cd16395be1 ("x86/sev-es: Add SEV-ES Feature Detection")
  ed7bde7a6dab521e ("cpufreq: intel_pstate: Allow enable/disable energy efficiency")
  f0f2f9feb4ee6f28 ("x86/msr-index: Define an IA32_PASID MSR")

That cause these changes in tooling:

  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh &gt; before
  $ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh &gt; after
  $ diff -u before after
  --- before	2020-10-19 13:27:33.195274425 -0300
  +++ after	2020-10-19 13:27:44.144507610 -0300
  @@ -113,6 +113,8 @@
   	[0x00000309] = "CORE_PERF_FIXED_CTR0",
   	[0x0000030a] = "CORE_PERF_FIXED_CTR1",
   	[0x0000030b] = "CORE_PERF_FIXED_CTR2",
  +	[0x0000030c] = "CORE_PERF_FIXED_CTR3",
  +	[0x00000329] = "PERF_METRICS",
   	[0x00000345] = "IA32_PERF_CAPABILITIES",
   	[0x0000038d] = "CORE_PERF_FIXED_CTR_CTRL",
   	[0x0000038e] = "CORE_PERF_GLOBAL_STATUS",
  @@ -222,6 +224,7 @@
   	[0x00000774] = "HWP_REQUEST",
   	[0x00000777] = "HWP_STATUS",
   	[0x00000d90] = "IA32_BNDCFGS",
  +	[0x00000d93] = "IA32_PASID",
   	[0x00000da0] = "IA32_XSS",
   	[0x00000dc0] = "LBR_INFO_0",
   	[0x00000ffc] = "IA32_BNDCFGS_RSVD",
  @@ -279,6 +282,7 @@
   	[0xc0010115 - x86_AMD_V_KVM_MSRs_offset] = "VM_IGNNE",
   	[0xc0010117 - x86_AMD_V_KVM_MSRs_offset] = "VM_HSAVE_PA",
   	[0xc001011f - x86_AMD_V_KVM_MSRs_offset] = "AMD64_VIRT_SPEC_CTRL",
  +	[0xc0010130 - x86_AMD_V_KVM_MSRs_offset] = "AMD64_SEV_ES_GHCB",
   	[0xc0010131 - x86_AMD_V_KVM_MSRs_offset] = "AMD64_SEV",
   	[0xc0010140 - x86_AMD_V_KVM_MSRs_offset] = "AMD64_OSVW_ID_LENGTH",
   	[0xc0010141 - x86_AMD_V_KVM_MSRs_offset] = "AMD64_OSVW_STATUS",
  $

Which causes these parts of tools/perf/ to be rebuilt:

  CC       /tmp/build/perf/trace/beauty/tracepoints/x86_msr.o
  DESCEND  plugins
  GEN      /tmp/build/perf/python/perf.so
  INSTALL  trace_plugins
  LD       /tmp/build/perf/trace/beauty/tracepoints/perf-in.o
  LD       /tmp/build/perf/trace/beauty/perf-in.o
  LD       /tmp/build/perf/perf-in.o
  LINK     /tmp/build/perf/per

At some point these should just be tables read by perf on demand.

This addresses this perf tools build warning:

  diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Joerg Roedel &lt;jroedel@suse.de&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Kim Phillips &lt;kim.phillips@amd.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools x86 headers: Update required-features.h header from the kernel</title>
<updated>2020-11-03T11:36:25Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-10-19T16:24:52Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=8b2fc25a945b125c7ee4c36b048ad65f7c04105e'/>
<id>urn:sha1:8b2fc25a945b125c7ee4c36b048ad65f7c04105e</id>
<content type='text'>
To pick the changes from:

  ecac71816a1829c0 ("x86/paravirt: Use CONFIG_PARAVIRT_XXL instead of CONFIG_PARAVIRT")

That don entail any changes in tooling, just addressing these perf tools
build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/required-features.h' differs from latest version at 'arch/x86/include/asm/required-features.h'
  diff -u tools/arch/x86/include/asm/required-features.h arch/x86/include/asm/required-features.h

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Juergen Gross &lt;jgross@suse.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools x86 headers: Update cpufeatures.h headers copies</title>
<updated>2020-11-03T11:36:12Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-10-19T16:21:04Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=40a6bbf5149c7302bd7515fb5e2c3d12bac462f5'/>
<id>urn:sha1:40a6bbf5149c7302bd7515fb5e2c3d12bac462f5</id>
<content type='text'>
To pick the changes from:

  5866e9205b47a983 ("x86/cpu: Add hardware-enforced cache coherency as a CPUID feature")
  ff4f82816dff28ff ("x86/cpufeatures: Enumerate ENQCMD and ENQCMDS instructions")
  360e7c5c4ca4fd8e ("x86/cpufeatures: Add SEV-ES CPU feature")
  18ec63faefb3fd31 ("x86/cpufeatures: Enumerate TSX suspend load address tracking instructions")
  e48cb1a3fb916500 ("x86/resctrl: Enumerate per-thread MBA controls")

Which don't cause any changes in tooling, just addresses these build
warnings:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
  diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/disabled-features.h' differs from latest version at 'arch/x86/include/asm/disabled-features.h'
  diff -u tools/arch/x86/include/asm/disabled-features.h arch/x86/include/asm/disabled-features.h

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Krish Sadhukhan &lt;krish.sadhukhan@oracle.com&gt;
Cc: Kyung Min Park &lt;kyung.min.park@intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Tom Lendacky &lt;thomas.lendacky@amd.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>parisc: Add MAP_UNINITIALIZED define</title>
<updated>2020-10-15T06:10:39Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2020-10-12T06:50:51Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=4a770b413fe91d5d271e29a50a1f23cf189b4d2e'/>
<id>urn:sha1:4a770b413fe91d5d271e29a50a1f23cf189b4d2e</id>
<content type='text'>
We will not allow unitialized anon mmaps, but we need this define
to prevent build errors, e.g. the debian foot package.

Suggested-by: John David Anglin &lt;dave.anglin@bell.net&gt;
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
</entry>
<entry>
<title>Merge tag 'x86_seves_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-10-14T17:21:34Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-10-14T17:21:34Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=da9803dfd3955bd2f9909d55e23f188ad76dbe58'/>
<id>urn:sha1:da9803dfd3955bd2f9909d55e23f188ad76dbe58</id>
<content type='text'>
Pull x86 SEV-ES support from Borislav Petkov:
 "SEV-ES enhances the current guest memory encryption support called SEV
  by also encrypting the guest register state, making the registers
  inaccessible to the hypervisor by en-/decrypting them on world
  switches. Thus, it adds additional protection to Linux guests against
  exfiltration, control flow and rollback attacks.

  With SEV-ES, the guest is in full control of what registers the
  hypervisor can access. This is provided by a guest-host exchange
  mechanism based on a new exception vector called VMM Communication
  Exception (#VC), a new instruction called VMGEXIT and a shared
  Guest-Host Communication Block which is a decrypted page shared
  between the guest and the hypervisor.

  Intercepts to the hypervisor become #VC exceptions in an SEV-ES guest
  so in order for that exception mechanism to work, the early x86 init
  code needed to be made able to handle exceptions, which, in itself,
  brings a bunch of very nice cleanups and improvements to the early
  boot code like an early page fault handler, allowing for on-demand
  building of the identity mapping. With that, !KASLR configurations do
  not use the EFI page table anymore but switch to a kernel-controlled
  one.

  The main part of this series adds the support for that new exchange
  mechanism. The goal has been to keep this as much as possibly separate
  from the core x86 code by concentrating the machinery in two
  SEV-ES-specific files:

    arch/x86/kernel/sev-es-shared.c
    arch/x86/kernel/sev-es.c

  Other interaction with core x86 code has been kept at minimum and
  behind static keys to minimize the performance impact on !SEV-ES
  setups.

  Work by Joerg Roedel and Thomas Lendacky and others"

* tag 'x86_seves_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (73 commits)
  x86/sev-es: Use GHCB accessor for setting the MMIO scratch buffer
  x86/sev-es: Check required CPU features for SEV-ES
  x86/efi: Add GHCB mappings when SEV-ES is active
  x86/sev-es: Handle NMI State
  x86/sev-es: Support CPU offline/online
  x86/head/64: Don't call verify_cpu() on starting APs
  x86/smpboot: Load TSS and getcpu GDT entry before loading IDT
  x86/realmode: Setup AP jump table
  x86/realmode: Add SEV-ES specific trampoline entry point
  x86/vmware: Add VMware-specific handling for VMMCALL under SEV-ES
  x86/kvm: Add KVM-specific VMMCALL handling under SEV-ES
  x86/paravirt: Allow hypervisor-specific VMMCALL handling under SEV-ES
  x86/sev-es: Handle #DB Events
  x86/sev-es: Handle #AC Events
  x86/sev-es: Handle VMMCALL Events
  x86/sev-es: Handle MWAIT/MWAITX Events
  x86/sev-es: Handle MONITOR/MONITORX Events
  x86/sev-es: Handle INVD Events
  x86/sev-es: Handle RDPMC Events
  x86/sev-es: Handle RDTSC(P) Events
  ...
</content>
</entry>
<entry>
<title>Merge tag 'objtool-core-2020-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2020-10-14T17:13:37Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-10-14T17:13:37Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=6873139ed078bfe0341d4cbb69e5af1b323bf532'/>
<id>urn:sha1:6873139ed078bfe0341d4cbb69e5af1b323bf532</id>
<content type='text'>
Pull objtool updates from Ingo Molnar:
 "Most of the changes are cleanups and reorganization to make the
  objtool code more arch-agnostic. This is in preparation for non-x86
  support.

  Other changes:

   - KASAN fixes

   - Handle unreachable trap after call to noreturn functions better

   - Ignore unreachable fake jumps

   - Misc smaller fixes &amp; cleanups"

* tag 'objtool-core-2020-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  perf build: Allow nested externs to enable BUILD_BUG() usage
  objtool: Allow nested externs to enable BUILD_BUG()
  objtool: Permit __kasan_check_{read,write} under UACCESS
  objtool: Ignore unreachable trap after call to noreturn functions
  objtool: Handle calling non-function symbols in other sections
  objtool: Ignore unreachable fake jumps
  objtool: Remove useless tests before save_reg()
  objtool: Decode unwind hint register depending on architecture
  objtool: Make unwind hint definitions available to other architectures
  objtool: Only include valid definitions depending on source file type
  objtool: Rename frame.h -&gt; objtool.h
  objtool: Refactor jump table code to support other architectures
  objtool: Make relocation in alternative handling arch dependent
  objtool: Abstract alternative special case handling
  objtool: Move macros describing structures to arch-dependent code
  objtool: Make sync-check consider the target architecture
  objtool: Group headers to check in a single list
  objtool: Define 'struct orc_entry' only when needed
  objtool: Skip ORC entry creation for non-text sections
  objtool: Move ORC logic out of check()
  ...
</content>
</entry>
<entry>
<title>x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()</title>
<updated>2020-10-06T09:18:04Z</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2020-10-06T03:40:16Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/linux/commit/?id=ec6347bb43395cb92126788a1a5b25302543f815'/>
<id>urn:sha1:ec6347bb43395cb92126788a1a5b25302543f815</id>
<content type='text'>
In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.

Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:

  On Fri, May 1, 2020 at 11:28 AM Linus Torvalds &lt;torvalds@linux-foundation.org&gt; wrote:
  &gt;
  &gt; On Thu, Apr 30, 2020 at 6:21 PM Dan Williams &lt;dan.j.williams@intel.com&gt; wrote:
  &gt; &gt;
  &gt; &gt; However now I see that copy_user_generic() works for the wrong reason.
  &gt; &gt; It works because the exception on the source address due to poison
  &gt; &gt; looks no different than a write fault on the user address to the
  &gt; &gt; caller, it's still just a short copy. So it makes copy_to_user() work
  &gt; &gt; for the wrong reason relative to the name.
  &gt;
  &gt; Right.
  &gt;
  &gt; And it won't work that way on other architectures. On x86, we have a
  &gt; generic function that can take faults on either side, and we use it
  &gt; for both cases (and for the "in_user" case too), but that's an
  &gt; artifact of the architecture oddity.
  &gt;
  &gt; In fact, it's probably wrong even on x86 - because it can hide bugs -
  &gt; but writing those things is painful enough that everybody prefers
  &gt; having just one function.

Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().

Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.

One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.

 [ bp: Massage a bit. ]

Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Tony Luck &lt;tony.luck@intel.com&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com
</content>
</entry>
</feed>
