Commit Graph

116 Commits

Author SHA1 Message Date
Kees Cook
1f730d4ae6 x86/entry: Work around Clang __bdos() bug
[ Upstream commit 3e1730842f142add55dc658929221521a9ea62b6 ]

Clang produces a false positive when building with CONFIG_FORTIFY_SOURCE=y
and CONFIG_UBSAN_BOUNDS=y when operating on an array with a dynamic
offset. Work around this by using a direct assignment of an empty
instance. Avoids this warning:

../include/linux/fortify-string.h:309:4: warning: call to __write_overflow_field declared with 'warn
ing' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wat
tribute-warning]
                        __write_overflow_field(p_size_field, size);
                        ^

which was isolated to the memset() call in xen_load_idt().

Note that this looks very much like another bug that was worked around:
https://github.com/ClangBuiltLinux/linux/issues/1592

Cc: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: xen-devel@lists.xenproject.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/lkml/41527d69-e8ab-3f86-ff37-6b298c01d5bc@oracle.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:25:45 +02:00
Jan Beulich
3c958dbcba x86/Xen: streamline (and fix) PV CPU enumeration
[ Upstream commit e25a8d959992f61b64a58fc62fb7951dc6f31d1f ]

This started out with me noticing that "dom0_max_vcpus=<N>" with <N>
larger than the number of physical CPUs reported through ACPI tables
would not bring up the "excess" vCPU-s. Addressing this is the primary
purpose of the change; CPU maps handling is being tidied only as far as
is necessary for the change here (with the effect of also avoiding the
setting up of too much per-CPU infrastructure, i.e. for CPUs which can
never come online).

Noticing that xen_fill_possible_map() is called way too early, whereas
xen_filter_cpu_maps() is called too late (after per-CPU areas were
already set up), and further observing that each of the functions serves
only one of Dom0 or DomU, it looked like it was better to simplify this.
Use the .get_smp_config hook instead, uniformly for Dom0 and DomU.
xen_fill_possible_map() can be dropped altogether, while
xen_filter_cpu_maps() is re-purposed but not otherwise changed.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/2dbd5f0a-9859-ca2d-085e-a02f7166c610@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-23 12:01:00 +01:00
Juergen Gross
4bbbc9c4f3 x86/pv: Switch SWAPGS to ALTERNATIVE
[ Upstream commit 53c9d9240944088274aadbbbafc6138ca462db4f ]

SWAPGS is used only for interrupts coming from user mode or for
returning to user mode. So there is no reason to use the PARAVIRT
framework, as it can easily be replaced by an ALTERNATIVE depending
on X86_FEATURE_XENPV.

There are several instances using the PV-aware SWAPGS macro in paths
which are never executed in a Xen PV guest. Replace those with the
plain swapgs instruction. For SWAPGS_UNSAFE_STACK the same applies.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210120135555.32594-5-jgross@suse.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-08 09:03:27 +01:00
Jan Beulich
f792828491 xen/x86: fix PV trap handling on secondary processors
commit 0594c58161b6e0f3da8efa9c6e3d4ba52b652717 upstream.

The initial observation was that in PV mode under Xen 32-bit user space
didn't work anymore. Attempts of system calls ended in #GP(0x402). All
of the sudden the vector 0x80 handler was not in place anymore. As it
turns out up to 5.13 redundant initialization did occur: Once from
cpu_initialize_context() (through its VCPUOP_initialise hypercall) and a
2nd time while each CPU was brought fully up. This 2nd initialization is
now gone, uncovering that the 1st one was flawed: Unlike for the
set_trap_table hypercall, a full virtual IDT needs to be specified here;
the "vector" fields of the individual entries are of no interest. With
many (kernel) IDT entries still(?) (i.e. at that point at least) empty,
the syscall vector 0x80 ended up in slot 0x20 of the virtual IDT, thus
becoming the domain's handler for vector 0x20.

Make xen_convert_trap_info() fit for either purpose, leveraging the fact
that on the xen_copy_trap_info() path the table starts out zero-filled.
This includes moving out the writing of the sentinel, which would also
have lead to a buffer overrun in the xen_copy_trap_info() case if all
(kernel) IDT entries were populated. Convert the writing of the sentinel
to clearing of the entire table entry rather than just the address
field.

(I didn't bother trying to identify the commit which uncovered the issue
in 5.14; the commit named below is the one which actually introduced the
bad code.)

Fixes: f87e4cac4f ("xen: SMP guest support")
Cc: stable@vger.kernel.org
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/7a266932-092e-b68f-f2bb-1473b61adc6e@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-30 10:10:59 +02:00
Juergen Gross
1a5a3ba21a xen: reset legacy rtc flag for PV domU
commit f68aa100d815b5b4467fd1c3abbe3b99d65fd028 upstream.

A Xen PV guest doesn't have a legacy RTC device, so reset the legacy
RTC flag. Otherwise the following WARN splat will occur at boot:

[    1.333404] WARNING: CPU: 1 PID: 1 at /home/gross/linux/head/drivers/rtc/rtc-mc146818-lib.c:25 mc146818_get_time+0x1be/0x210
[    1.333404] Modules linked in:
[    1.333404] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G        W         5.14.0-rc7-default+ #282
[    1.333404] RIP: e030:mc146818_get_time+0x1be/0x210
[    1.333404] Code: c0 64 01 c5 83 fd 45 89 6b 14 7f 06 83 c5 64 89 6b 14 41 83 ec 01 b8 02 00 00 00 44 89 63 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 <0f> 0b 48 c7 c7 30 0e ef 82 4c 89 e6 e8 71 2a 24 00 48 c7 c0 ff ff
[    1.333404] RSP: e02b:ffffc90040093df8 EFLAGS: 00010002
[    1.333404] RAX: 00000000000000ff RBX: ffffc90040093e34 RCX: 0000000000000000
[    1.333404] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000d
[    1.333404] RBP: ffffffff82ef0e30 R08: ffff888005013e60 R09: 0000000000000000
[    1.333404] R10: ffffffff82373e9b R11: 0000000000033080 R12: 0000000000000200
[    1.333404] R13: 0000000000000000 R14: 0000000000000002 R15: ffffffff82cdc6d4
[    1.333404] FS:  0000000000000000(0000) GS:ffff88807d440000(0000) knlGS:0000000000000000
[    1.333404] CS:  10000e030 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.333404] CR2: 0000000000000000 CR3: 000000000260a000 CR4: 0000000000050660
[    1.333404] Call Trace:
[    1.333404]  ? wakeup_sources_sysfs_init+0x30/0x30
[    1.333404]  ? rdinit_setup+0x2b/0x2b
[    1.333404]  early_resume_init+0x23/0xa4
[    1.333404]  ? cn_proc_init+0x36/0x36
[    1.333404]  do_one_initcall+0x3e/0x200
[    1.333404]  kernel_init_freeable+0x232/0x28e
[    1.333404]  ? rest_init+0xd0/0xd0
[    1.333404]  kernel_init+0x16/0x120
[    1.333404]  ret_from_fork+0x1f/0x30

Cc: <stable@vger.kernel.org>
Fixes: 8d152e7a5c ("x86/rtc: Replace paravirt rtc check with platform legacy quirk")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20210903084937.19392-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22 12:27:54 +02:00
Peter Zijlstra
59aa5c91f8 x86/xen: Fix noinstr fail in exc_xen_unknown_trap()
[ Upstream commit 4c9c26f1e67648f41f28f8c997c5c9467a3dbbe4 ]

Fix:

  vmlinux.o: warning: objtool: exc_xen_unknown_trap()+0x7: call to printk() leaves .noinstr.text section

Fixes: 2e92493637a0 ("x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210621120120.606560778@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-30 08:47:18 -04:00
Jan Beulich
e2c26ddd4e x86/Xen: swap NX determination and GDT setup on BSP
commit ae897fda4f507e4b239f0bdfd578b3688ca96fb4 upstream.

xen_setup_gdt(), via xen_load_gdt_boot(), wants to adjust page tables.
For this to work when NX is not available, x86_configure_nx() needs to
be called first.

[jgross] Note that this is a revert of 36104cb901 ("x86/xen:
Delay get_cpu_cap until stack canary is established"), which is possible
now that we no longer support running as PV guest in 32-bit mode.

Cc: <stable.vger.kernel.org> # 5.9
Fixes: 36104cb901 ("x86/xen: Delay get_cpu_cap until stack canary is established")
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Link: https://lore.kernel.org/r/12a866b0-9e89-59f7-ebeb-a2a6cec0987a@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2021-05-26 12:06:57 +02:00
Juergen Gross
b444b86e37 x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled
commit 2e92493637a09547734f92c62a2471f6f0cb9a2c upstream.

When booting a kernel which has been built with CONFIG_AMD_MEM_ENCRYPT
enabled as a Xen pv guest a warning is issued for each processor:

[    5.964347] ------------[ cut here ]------------
[    5.968314] WARNING: CPU: 0 PID: 1 at /home/gross/linux/head/arch/x86/xen/enlighten_pv.c:660 get_trap_addr+0x59/0x90
[    5.972321] Modules linked in:
[    5.976313] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W         5.11.0-rc5-default #75
[    5.980313] Hardware name: Dell Inc. OptiPlex 9020/0PC5F7, BIOS A05 12/05/2013
[    5.984313] RIP: e030:get_trap_addr+0x59/0x90
[    5.988313] Code: 42 10 83 f0 01 85 f6 74 04 84 c0 75 1d b8 01 00 00 00 c3 48 3d 00 80 83 82 72 08 48 3d 20 81 83 82 72 0c b8 01 00 00 00 eb db <0f> 0b 31 c0 c3 48 2d 00 80 83 82 48 ba 72 1c c7 71 1c c7 71 1c 48
[    5.992313] RSP: e02b:ffffc90040033d38 EFLAGS: 00010202
[    5.996313] RAX: 0000000000000001 RBX: ffffffff82a141d0 RCX: ffffffff8222ec38
[    6.000312] RDX: ffffffff8222ec38 RSI: 0000000000000005 RDI: ffffc90040033d40
[    6.004313] RBP: ffff8881003984a0 R08: 0000000000000007 R09: ffff888100398000
[    6.008312] R10: 0000000000000007 R11: ffffc90040246000 R12: ffff8884082182a8
[    6.012313] R13: 0000000000000100 R14: 000000000000001d R15: ffff8881003982d0
[    6.016316] FS:  0000000000000000(0000) GS:ffff888408200000(0000) knlGS:0000000000000000
[    6.020313] CS:  e030 DS: 0000 ES: 0000 CR0: 0000000080050033
[    6.024313] CR2: ffffc900020ef000 CR3: 000000000220a000 CR4: 0000000000050660
[    6.028314] Call Trace:
[    6.032313]  cvt_gate_to_trap.part.7+0x3f/0x90
[    6.036313]  ? asm_exc_double_fault+0x30/0x30
[    6.040313]  xen_convert_trap_info+0x87/0xd0
[    6.044313]  xen_pv_cpu_up+0x17a/0x450
[    6.048313]  bringup_cpu+0x2b/0xc0
[    6.052313]  ? cpus_read_trylock+0x50/0x50
[    6.056313]  cpuhp_invoke_callback+0x80/0x4c0
[    6.060313]  _cpu_up+0xa7/0x140
[    6.064313]  cpu_up+0x98/0xd0
[    6.068313]  bringup_nonboot_cpus+0x4f/0x60
[    6.072313]  smp_init+0x26/0x79
[    6.076313]  kernel_init_freeable+0x103/0x258
[    6.080313]  ? rest_init+0xd0/0xd0
[    6.084313]  kernel_init+0xa/0x110
[    6.088313]  ret_from_fork+0x1f/0x30
[    6.092313] ---[ end trace be9ecf17dceeb4f3 ]---

Reason is that there is no Xen pv trap entry for X86_TRAP_VC.

Fix that by adding a generic trap handler for unknown traps and wire all
unknown bare metal handlers to this generic handler, which will just
crash the system in case such a trap will ever happen.

Fixes: 0786138c78 ("x86/sev-es: Add a Runtime #VC Exception Handler")
Cc: <stable@vger.kernel.org> # v5.10
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:28:38 +01:00
Linus Torvalds
a09b1d7850 Merge tag 'for-linus-5.10b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:

 - two small cleanup patches

 - avoid error messages when initializing MCA banks in a Xen dom0

 - a small series for converting the Xen gntdev driver to use
   pin_user_pages*() instead of get_user_pages*()

 - intermediate fix for running as a Xen guest on Arm with KPTI enabled
   (the final solution will need new Xen functionality)

* tag 'for-linus-5.10b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: Fix typo in xen_pagetable_p2m_free()
  x86/xen: disable Firmware First mode for correctable memory errors
  xen/arm: do not setup the runstate info page if kpti is enabled
  xen: remove redundant initialization of variable ret
  xen/gntdev.c: Convert get_user_pages*() to pin_user_pages*()
  xen/gntdev.c: Mark pages as dirty
2020-10-14 10:34:45 -07:00
Linus Torvalds
6873139ed0 Merge tag 'objtool-core-2020-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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 & 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 -> 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()
  ...
2020-10-14 10:13:37 -07:00
Dan Williams
2dd57d3415 x86/numa: cleanup configuration dependent command-line options
Patch series "device-dax: Support sub-dividing soft-reserved ranges", v5.

The device-dax facility allows an address range to be directly mapped
through a chardev, or optionally hotplugged to the core kernel page
allocator as System-RAM.  It is the mechanism for converting persistent
memory (pmem) to be used as another volatile memory pool i.e.  the current
Memory Tiering hot topic on linux-mm.

In the case of pmem the nvdimm-namespace-label mechanism can sub-divide
it, but that labeling mechanism is not available / applicable to
soft-reserved ("EFI specific purpose") memory [3].  This series provides a
sysfs-mechanism for the daxctl utility to enable provisioning of
volatile-soft-reserved memory ranges.

The motivations for this facility are:

1/ Allow performance differentiated memory ranges to be split between
   kernel-managed and directly-accessed use cases.

2/ Allow physical memory to be provisioned along performance relevant
   address boundaries. For example, divide a memory-side cache [4] along
   cache-color boundaries.

3/ Parcel out soft-reserved memory to VMs using device-dax as a security
   / permissions boundary [5]. Specifically I have seen people (ab)using
   memmap=nn!ss (mark System-RAM as Persistent Memory) just to get the
   device-dax interface on custom address ranges. A follow-on for the VM
   use case is to teach device-dax to dynamically allocate 'struct page' at
   runtime to reduce the duplication of 'struct page' space in both the
   guest and the host kernel for the same physical pages.

[2]: http://lore.kernel.org/r/20200713160837.13774-11-joao.m.martins@oracle.com
[3]: http://lore.kernel.org/r/157309097008.1579826.12818463304589384434.stgit@dwillia2-desk3.amr.corp.intel.com
[4]: http://lore.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@dwillia2-desk3.amr.corp.intel.com
[5]: http://lore.kernel.org/r/20200110190313.17144-1-joao.m.martins@oracle.com

This patch (of 23):

In preparation for adding a new numa= option clean up the existing ones to
avoid ifdefs in numa_setup(), and provide feedback when the option is
numa=fake= option is invalid due to kernel config.  The same does not need
to be done for numa=noacpi, since the capability is already hard disabled
at compile-time.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jia He <justin.he@arm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Hulk Robot <hulkci@huawei.com>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: https://lkml.kernel.org/r/160106109960.30709.7379926726669669398.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/159643094279.4062302.17779410714418721328.stgit@dwillia2-desk3.amr.corp.intel.com
Link: https://lkml.kernel.org/r/159643094925.4062302.14979872973043772305.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:27 -07:00
Juergen Gross
d759af3857 x86/xen: disable Firmware First mode for correctable memory errors
When running as Xen dom0 the kernel isn't responsible for selecting the
error handling mode, this should be handled by the hypervisor.

So disable setting FF mode when running as Xen pv guest. Not doing so
might result in boot splats like:

[    7.509696] HEST: Enabling Firmware First mode for corrected errors.
[    7.510382] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 2.
[    7.510383] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 3.
[    7.510384] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 4.
[    7.510384] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 5.
[    7.510385] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 6.
[    7.510386] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 7.
[    7.510386] mce: [Firmware Bug]: Ignoring request to disable invalid MCA bank 8.

Reason is that the HEST ACPI table contains the real number of MCA
banks, while the hypervisor is emulating only 2 banks for guests.

Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20200925140751.31381-1-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-04 18:41:34 -05:00
Julien Thierry
00089c048e objtool: Rename frame.h -> objtool.h
Header frame.h is getting more code annotations to help objtool analyze
object files.

Rename the file to objtool.h.

[ jpoimboe: add objtool.h to MAINTAINERS ]

Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2020-09-10 10:43:13 -05:00
Juergen Gross
0cabf99149 x86/paravirt: Remove 32-bit support from CONFIG_PARAVIRT_XXL
The last 32-bit user of stuff under CONFIG_PARAVIRT_XXL is gone.

Remove 32-bit specific parts.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200815100641.26362-2-jgross@suse.com
2020-08-15 13:52:11 +02:00
Linus Torvalds
0520058d05 Merge tag 'for-linus-5.9-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull more xen updates from Juergen Gross:

 - Remove support for running as 32-bit Xen PV-guest.

   32-bit PV guests are rarely used, are lacking security fixes for
   Meltdown, and can be easily replaced by PVH mode. Another series for
   doing more cleanup will follow soon (removal of 32-bit-only pvops
   functionality).

 - Fixes and additional features for the Xen display frontend driver.

* tag 'for-linus-5.9-rc1b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  drm/xen-front: Pass dumb buffer data offset to the backend
  xen: Sync up with the canonical protocol definition in Xen
  drm/xen-front: Add YUYV to supported formats
  drm/xen-front: Fix misused IS_ERR_OR_NULL checks
  xen/gntdev: Fix dmabuf import with non-zero sgt offset
  x86/xen: drop tests for highmem in pv code
  x86/xen: eliminate xen-asm_64.S
  x86/xen: remove 32-bit Xen PV guest support
2020-08-14 13:34:37 -07:00
Juergen Gross
f2e39e8c4f x86/xen: drop tests for highmem in pv code
With support for 32-bit pv guests gone pure pv-code no longer needs to
test for highmem. Dropping those tests removes the need for flushing
in some places.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-08-11 08:27:07 +02:00
Juergen Gross
a13f2ef168 x86/xen: remove 32-bit Xen PV guest support
Xen is requiring 64-bit machines today and since Xen 4.14 it can be
built without 32-bit PV guest support. There is no need to carry the
burden of 32-bit PV guest support in the kernel any longer, as new
guests can be either HVM or PVH, or they can use a 64 bit kernel.

Remove the 32-bit Xen PV support from the kernel.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2020-08-11 08:26:48 +02:00
Colin Ian King
90fc73928f x86/ioperm: Initialize pointer bitmap with NULL rather than 0
The pointer bitmap is being initialized with a plain integer 0,
fix this by initializing it with a NULL instead.

Cleans up sparse warning:
arch/x86/xen/enlighten_pv.c:876:27: warning: Using plain integer
as NULL pointer

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200721100217.407975-1-colin.king@canonical.com
2020-07-26 19:52:55 +02:00
Andy Lutomirski
cadfad8701 x86/ioperm: Fix io bitmap invalidation on Xen PV
tss_invalidate_io_bitmap() wasn't wired up properly through the pvop
machinery, so the TSS and Xen's io bitmap would get out of sync
whenever disabling a valid io bitmap.

Add a new pvop for tss_invalidate_io_bitmap() to fix it.

This is XSA-329.

Fixes: 22fe5b0439 ("x86/ioperm: Move TSS bitmap update to exit to user work")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/d53075590e1f91c19f8af705059d3ff99424c020.1595030016.git.luto@kernel.org
2020-07-18 12:31:49 +02:00
Andy Lutomirski
f41f082422 x86/entry/xen: Route #DB correctly on Xen PV
On Xen PV, #DB doesn't use IST. It still needs to be correctly routed
depending on whether it came from user or kernel mode.

Get rid of DECLARE/DEFINE_IDTENTRY_XEN -- it was too hard to follow the
logic.  Instead, route #DB and NMI through DECLARE/DEFINE_IDTENTRY_RAW on
Xen, and do the right thing for #DB.  Also add more warnings to the
exc_debug* handlers to make this type of failure more obvious.

This fixes various forms of corruption that happen when usermode
triggers #DB on Xen PV.

Fixes: 4c0dcd8350 ("x86/entry: Implement user mode C entry points for #DB and #MCE")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/4163e733cce0b41658e252c6c6b3464f33fdff17.1593795633.git.luto@kernel.org
2020-07-04 19:47:25 +02:00
Christoph Hellwig
fe557319aa maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 10:57:41 -07:00
Thomas Gleixner
91eeafea1e x86/entry: Switch page fault exception to IDTENTRY_RAW
Convert page fault exceptions to IDTENTRY_RAW:

  - Implement the C entry point with DEFINE_IDTENTRY_RAW
  - Add the CR2 read into the exception handler
  - Add the idtentry_enter/exit_cond_rcu() invocations in
    in the regular page fault handler and in the async PF
    part.
  - Emit the ASM stub with DECLARE_IDTENTRY_RAW
  - Remove the ASM idtentry in 64-bit
  - Remove the CR2 read from 64-bit
  - Remove the open coded ASM entry code in 32-bit
  - Fix up the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202118.238455120@linutronix.de
2020-06-11 15:15:09 +02:00
Thomas Gleixner
c29c775a55 x86/entry: Convert double fault exception to IDTENTRY_DF
Convert #DF to IDTENTRY_DF
  - Implement the C entry point with DEFINE_IDTENTRY_DF
  - Emit the ASM stub with DECLARE_IDTENTRY_DF on 64bit
  - Remove the ASM idtentry in 64bit
  - Adjust the 32bit shim code
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135315.583415264@linutronix.de
2020-06-11 15:15:03 +02:00
Thomas Gleixner
2bbc68f837 x86/entry: Convert Debug exception to IDTENTRY_DB
Convert #DB to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY_DB
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.900297476@linutronix.de
2020-06-11 15:14:59 +02:00
Thomas Gleixner
6271fef00b x86/entry: Convert NMI to IDTENTRY_NMI
Convert #NMI to IDTENTRY_NMI:
  - Implement the C entry point with DEFINE_IDTENTRY_NMI
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.609932306@linutronix.de
2020-06-11 15:14:58 +02:00
Thomas Gleixner
8cd501c1fa x86/entry: Convert Machine Check to IDTENTRY_IST
Convert #MC to IDTENTRY_MCE:
  - Implement the C entry points with DEFINE_IDTENTRY_MCE
  - Emit the ASM stub with DECLARE_IDTENTRY_MCE
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the error code from *machine_check_vector() as
    it is always 0 and not used by any of the functions
    it can point to. Fixup all the functions as well.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135314.334980426@linutronix.de
2020-06-11 15:14:57 +02:00
Thomas Gleixner
8edd7e37ae x86/entry: Convert INT3 exception to IDTENTRY_RAW
Convert #BP to IDTENTRY_RAW:
  - Implement the C entry point with DEFINE_IDTENTRY_RAW
  - Invoke idtentry_enter/exit() from the function body
  - Emit the ASM stub with DECLARE_IDTENTRY_RAW
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

This could be a plain IDTENTRY, but as Peter pointed out INT3 is broken
vs. the static key in the context tracking code as this static key might be
in the state of being patched and has an int3 which would recurse forever.
IDTENTRY_RAW is therefore chosen to allow addressing this issue without
lots of code churn.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135313.938474960@linutronix.de
2020-06-11 15:14:55 +02:00
Thomas Gleixner
48227e21f7 x86/entry: Convert SIMD coprocessor error exception to IDTENTRY
Convert #XF to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Handle INVD_BUG in C
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134906.021552202@linutronix.de
2020-06-11 15:14:52 +02:00
Thomas Gleixner
436608bb00 x86/entry: Convert Alignment check exception to IDTENTRY
Convert #AC to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.928967113@linutronix.de
2020-06-11 15:14:51 +02:00
Thomas Gleixner
14a8bd2aa7 x86/entry: Convert Coprocessor error exception to IDTENTRY
Convert #MF to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.838823510@linutronix.de
2020-06-11 15:14:51 +02:00
Thomas Gleixner
dad7106f81 x86/entry: Convert Spurious interrupt bug exception to IDTENTRY
Convert #SPURIOUS to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.728077036@linutronix.de
2020-06-11 15:14:50 +02:00
Thomas Gleixner
be4c11afbb x86/entry: Convert General protection exception to IDTENTRY
Convert #GP to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.637269946@linutronix.de
2020-06-11 15:14:50 +02:00
Thomas Gleixner
fd9689bf91 x86/entry: Convert Stack segment exception to IDTENTRY
Convert #SS to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134905.539867572@linutronix.de
2020-06-11 15:14:49 +02:00
Thomas Gleixner
99a3fb8d01 x86/entry: Convert Segment not present exception to IDTENTRY
Convert #NP to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134905.443591450@linutronix.de
2020-06-11 15:14:49 +02:00
Thomas Gleixner
97b3d290b8 x86/entry: Convert Invalid TSS exception to IDTENTRY
Convert #TS to IDTENTRY_ERRORCODE:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134905.350676449@linutronix.de
2020-06-11 15:14:49 +02:00
Thomas Gleixner
f95658fdb5 x86/entry: Convert Coprocessor segment overrun exception to IDTENTRY
Convert #OLD_MF to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134905.838823510@linutronix.de
2020-06-11 15:14:48 +02:00
Thomas Gleixner
866ae2ccee x86/entry: Convert Device not available exception to IDTENTRY
Convert #NM to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134905.056243863@linutronix.de
2020-06-11 15:14:47 +02:00
Thomas Gleixner
49893c5cb2 x86/entry: Convert Invalid Opcode exception to IDTENTRY
Convert #UD to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Fixup the FOOF bug call in fault.c
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.955511913@linutronix.de
2020-06-11 15:14:47 +02:00
Thomas Gleixner
58d9c81fac x86/entry: Convert Bounds exception to IDTENTRY
Convert #BR to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes
  - Remove the RCU warning as the new entry macro ensures correctness

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.863001309@linutronix.de
2020-06-11 15:14:46 +02:00
Thomas Gleixner
4b6b9111c0 x86/entry: Convert Overflow exception to IDTENTRY
Convert #OF to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code
  - Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134904.771457898@linutronix.de
2020-06-11 15:14:46 +02:00
Thomas Gleixner
9d06c4027f x86/entry: Convert Divide Error to IDTENTRY
Convert #DE to IDTENTRY:
  - Implement the C entry point with DEFINE_IDTENTRY
  - Emit the ASM stub with DECLARE_IDTENTRY
  - Remove the ASM idtentry in 64bit
  - Remove the open coded ASM entry code in 32bit
  - Fixup the XEN/PV code

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505134904.663914713@linutronix.de
2020-06-11 15:14:46 +02:00
Mike Rapoport
e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Juergen Gross
99bcd4a6e5 x86/ioperm: Add new paravirt function update_io_bitmap()
Commit 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm()
as well") reworked the iopl syscall to use I/O bitmaps.

Unfortunately this broke Xen PV domains using that syscall as there is
currently no I/O bitmap support in PV domains.

Add I/O bitmap support via a new paravirt function update_io_bitmap which
Xen PV domains can use to update their I/O bitmaps via a hypercall.

Fixes: 111e7b15cf ("x86/ioperm: Extend IOPL config to control ioperm() as well")
Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lkml.kernel.org/r/20200218154712.25490-1-jgross@suse.com
2020-02-29 12:43:09 +01:00
Linus Torvalds
54dedb5b57 Merge tag 'for-linus-5.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
 "Two small fixes for Xen:

   - a fix to avoid warnings with new gcc

   - a fix for incorrectly disabled interrupts when calling
     _cond_resched()"

* tag 'for-linus-5.6-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Enable interrupts when calling _cond_resched()
  x86/xen: Distribute switch variables for initialization
2020-02-21 16:10:10 -08:00
Kees Cook
9038ec99ce x86/xen: Distribute switch variables for initialization
Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

arch/x86/xen/enlighten_pv.c: In function ‘xen_write_msr_safe’:
arch/x86/xen/enlighten_pv.c:904:12: warning: statement will never be executed [-Wswitch-unreachable]
  904 |   unsigned which;
      |            ^~~~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200220062318.69299-1-keescook@chromium.org
Reviewed-by: Juergen Gross <jgross@suse.com>
[boris: made @which an 'unsigned int']
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-02-20 10:16:40 -06:00
Thomas Gleixner
979923871f x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
Tony reported a boot regression caused by the recent workaround for systems
which have a disabled (clock gate off) PIT.

On his machine the kernel fails to initialize the PIT because
apic_needs_pit() does not take into account whether the local APIC
interrupt delivery mode will actually allow to setup and use the local
APIC timer. This should be easy to reproduce with acpi=off on the
command line which also disables HPET.

Due to the way the PIT/HPET and APIC setup ordering works (APIC setup can
require working PIT/HPET) the information is not available at the point
where apic_needs_pit() makes this decision.

To address this, split out the interrupt mode selection from
apic_intr_mode_init(), invoke the selection before making the decision
whether PIT is required or not, and add the missing checks into
apic_needs_pit().

Fixes: c8c4076723 ("x86/timer: Skip PIT initialization on modern chipsets")
Reported-by: Anthony Buckley <tony.buckley000@gmail.com>
Tested-by: Anthony Buckley <tony.buckley000@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Daniel Drake <drake@endlessm.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206125
Link: https://lore.kernel.org/r/87sgk6tmk2.fsf@nanos.tec.linutronix.de
2020-01-29 12:50:12 +01:00
Thomas Gleixner
a24ca99768 x86/iopl: Remove legacy IOPL option
The IOPL emulation via the I/O bitmap is sufficient. Remove the legacy
cruft dealing with the (e)flags based IOPL mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com> (Paravirt and Xen parts)
Acked-by: Andy Lutomirski <luto@kernel.org>
2019-11-16 11:24:05 +01:00
Linus Torvalds
4fac2407f8 Merge tag 'for-linus-5.4-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixlet from Juergen Gross:
 "Just one patch for issuing a deprecation warning for 32-bit Xen pv
  guests"

* tag 'for-linus-5.4-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: issue deprecation warning for 32-bit pv guest
2019-10-26 06:32:12 -04:00
Juergen Gross
6ccae60d01 xen: issue deprecation warning for 32-bit pv guest
Support for the kernel as Xen 32-bit PV guest will soon be removed.
Issue a warning when booted as such.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2019-10-25 09:53:18 -04:00
Andrew Cooper
83b584d9c6 x86/paravirt: Drop {read,write}_cr8() hooks
There is a lot of infrastructure for functionality which is used
exclusively in __{save,restore}_processor_state() on the suspend/resume
path.

cr8 is an alias of APIC_TASKPRI, and APIC_TASKPRI is saved/restored by
lapic_{suspend,resume}().  Saving and restoring cr8 independently of the
rest of the Local APIC state isn't a clever thing to be doing.

Delete the suspend/resume cr8 handling, which shrinks the size of struct
saved_context, and allows for the removal of both PVOPS.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20190715151641.29210-1-andrew.cooper3@citrix.com
2019-07-22 10:12:33 +02:00