Commit Graph
43682 Commits
Author SHA1 Message Date
Julien Grall 07aebcd55f Revert "xen/arm64: io: Support instructions (for which ISS is not valid) on emulated MMIO region using MMIO/ioreq handler"
This reverts commit 9e5a68a665.

This breaks boot on arm32:

https://lore.kernel.org/xen-devel/osstest-168589-mainreport@xen.org/T/#u
2022-03-14 23:01:02 +00:00
Julien Grall 133ba7ae76 Revert "xen/arm64: io: Handle the abort due to access to stage1 translation table"
This reverts commit fef5531fd8.

This depends on patch 9e5a68a665 which
will need to be reverted as it break boot on arm32.

https://lore.kernel.org/xen-devel/osstest-168589-mainreport@xen.org/T/#u

Signed-off-by: Julien Grall <jgrall@amazon.com>
2022-03-14 23:00:05 +00:00
Ayan Kumar Halder fef5531fd8 xen/arm64: io: Handle the abort due to access to stage1 translation table
If the abort was caused due to access to stage1 translation table, Xen
will try to set the p2m entry (assuming that the Stage 1 translation
table is in the non MMIO region).
If there is no such entry found, then Xen will try to map the address as
a MMIO region (assuming that the Stage 1 translation table is in the
direct MMIO region).

If that fails as well, then there are the two following scenarios:-
1. Stage 1 translation table being in an emulated MMIO region - Xen
can read the region, but it has no way to return the value read to the
CPU page table walker (which tries to go through the stage1 tables to
resolve the translation fault).

2. Stage 1 translation table address is invalid.

In both the above scenarios, Xen will forward the abort to the guest.

Signed-off-by: Ayan Kumar Halder <ayankuma@xilinx.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
2022-03-14 18:02:16 +00:00
Ayan Kumar Halder 9e5a68a665 xen/arm64: io: Support instructions (for which ISS is not valid) on emulated MMIO region using MMIO/ioreq handler
When an instruction is trapped in Xen due to translation fault, Xen
checks if the ISS is invalid (for data abort) or it is an instruction
abort. If so, Xen tries to resolve the translation fault using p2m page
tables. In case of data abort, Xen will try to map the mmio region to
the guest (ie tries to emulate the mmio region).

If the ISS is not valid and it is a data abort, then Xen tries to
decode the instruction. In case of ioreq, Xen  saves the decoding state,
rn and imm9 to vcpu_io. Whenever the vcpu handles the ioreq successfully,
it will read the decoding state to determine if the instruction decoded
was a ldr/str post indexing (ie INSTR_LDR_STR_POSTINDEXING). If so, it
uses these details to post increment rn.

In case of mmio handler, if the mmio operation was successful, then Xen
retrives the decoding state, rn and imm9. For state ==
INSTR_LDR_STR_POSTINDEXING, Xen will update rn.

If there is an error encountered while decoding/executing the instruction,
Xen will forward the abort to the guest.

Also, the logic to infer the type of instruction has been moved from
try_handle_mmio() to try_decode_instruction() which is called before.
try_handle_mmio() is solely responsible for handling the mmio operation.

Signed-off-by: Ayan Kumar Halder <ayankuma@xilinx.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2022-03-14 17:58:40 +00:00
Ayan Kumar Halder f9dd8436e3 xen/arm64: Decode ldr/str post increment operations
At the moment, Xen does not decode any of the arm64 instructions. This
means that when hsr_dabt.isv == 0, Xen cannot handle those instructions.
This will lead to Xen to abort the guests (from which those instructions
originate).

With this patch, Xen is able to decode ldr/str post indexing instructions.
These are a subset of instructions for which hsr_dabt.isv == 0.

The following instructions are now supported by Xen :-
1.      ldr     x2,    [x1],    #8
2.      ldr     w2,    [x1],    #-4
3.      ldr     x2,    [x1],    #-8
4.      ldr     w2,    [x1],    #4
5.      ldrh    w2,    [x1],    #2
6.      ldrb    w2,    [x1],    #1
7.      str     x2,    [x1],    #8
8.      str     w2,    [x1],    #-4
9.      strh    w2,    [x1],    #2
10.     strb    w2,    [x1],    #1

In the subsequent patch, decode_arm64() will get invoked when
hsr_dabt.isv == 0.

Signed-off-by: Ayan Kumar Halder <ayankuma@xilinx.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
2022-03-14 17:58:04 +00:00
Jan Beulich dedb0aa42c x86/build: use --orphan-handling linker option if available
As was e.g. making necessary 4b7fd8153d ("x86: fold sections in final
binaries"), arbitrary sections appearing without our linker script
placing them explicitly can be a problem. Have the linker make us aware
of such sections, so we would know that the script needs adjusting.

To deal with the resulting warnings:
- Retain .note.* explicitly for ELF, and discard all of them (except the
  earlier consumed .note.gnu.build-id) for PE/COFF.
- Have explicit statements for .got, .plt, and alike and add assertions
  that they're empty. No output sections will be created for these as
  long as they remain empty (or else the assertions would cause early
  failure anyway).
- Collect all .rela.* into a single section, with again an assertion
  added for the resulting section to be empty.
- Extend the enumerating of .debug_* to ELF. Note that for Clang adding
  of .debug_macinfo is necessary. Amend this by its Dwarf5 counterpart,
  .debug_macro, then as well (albeit more may need adding for full
  coverage).
- For LLVM ld also enumerate .symtab, .strtab, and .shstrtab.

Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2022-03-14 10:33:35 +01:00
Jan Beulich e2589ef652 IOMMU/x86: tidy adjust_irq_affinities hook
As of 3e56754b08 ("xen/cet: Fix __initconst_cf_clobber") there's no
need for a non-void return value anymore, as the hook functions are no
longer themselves passed to __initcall(). For the same reason the
iommu_enabled checks can now move from the individual functions to the
wrapper.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2022-03-14 10:32:40 +01:00
Roger Pau Monné 7b4b36fcba pci/ats: do not allow broken devices to be assigned to guests
Introduce a new field to mark devices as broken: having it set prevents
the device from being assigned to guests. Use the field in order to mark
ATS devices that have failed a flush when using VT-d as broken, thus
preventing them to be assigned to any guest.

This allows the device IOMMU context entry to be cleaned up properly, as
calling _pci_hide_device will just change the ownership of the device,
but the IOMMU context entry of the device would be left as-is. It would
also leak a VT-d Domain ID if using one, as removing the device from
its previous owner will allow releasing the IOMMU DID used by the device
without having cleaned up the context entry.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2022-03-14 10:30:02 +01:00
Roger Pau Monné 3f80988698 x86/vmx: remove dead code to create domains without a vLAPIC
After the removal of PVHv1 it's no longer supported to create a domain
using hardware virtualization extensions and without a local APIC:
PVHv2 mandates domains to always have a LAPIC. Remove some stale code
in VMCS construction and related helpers that catered for that
use-case.

No functional change.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
2022-03-14 10:29:24 +01:00
Jan Beulich 23658e8232 x86/time: further improve TSC / CPU freq calibration accuracy
Calibration logic assumes that the platform timer (HPET or ACPI PM
timer) and the TSC are read at about the same time. This assumption may
not hold when a long latency event (e.g. SMI or NMI) occurs between the
two reads. Reduce the risk of reading uncorrelated values by doing at
least four pairs of reads, using the tuple where the delta between the
enclosing TSC reads was smallest. From the fourth iteration onwards bail
if the new TSC delta isn't better (smaller) than the best earlier one.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2022-03-14 10:27:57 +01:00
Roger Pau Monne 6ff9a7e62b livepatch: set -f{function,data}-sections compiler option
If livepatching support is enabled build the hypervisor with
-f{function,data}-sections compiler options, which is required by the
livepatching tools to detect changes and create livepatches.

This shouldn't result in any functional change on the hypervisor
binary image, but does however require some changes in the linker
script in order to handle that each function and data item will now be
placed into its own section in object files. As a result add catch-all
for .text, .data and .bss in order to merge each individual item
section into the final image.

The main difference will be that .text.startup will end up being part
of .text rather than .init, and thus won't be freed. .text.exit will
also be part of .text rather than dropped. Overall this could make the
image bigger, and package some .text code in a sub-optimal way.

On Arm the .data.read_mostly needs to be moved ahead of the .data
section like it's already done on x86, so the .data.* catch-all
doesn't also include .data.read_mostly. The alignment of
.data.read_mostly also needs to be set to PAGE_SIZE so it doesn't end
up being placed at the tail of a read-only page from the previous
section. While there move the alignment of the .data section ahead of
the section declaration, like it's done for other sections.

The benefit of having CONFIG_LIVEPATCH enable those compiler option
is that the livepatch build tools no longer need to fiddle with the
build system in order to enable them. Note the current livepatch tools
are broken after the recent build changes due to the way they
attempt to set  -f{function,data}-sections.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-10 18:47:55 +00:00
Roger Pau Monne 4267a33b19 xen/build: put image header into a separate section
So it can be explicitly placed ahead of the rest of the .text content
in the linker script (and thus the resulting image). This is a
prerequisite for further work that will add a catch-all to the text
section (.text.*).

Note that placement of the sections inside of .text is also slightly
adjusted to be more similar to the position found in the default GNU
ld linker script.

The special handling of the object file containing the header data as
the first object file passed to the linker command line can also be
removed.

While there also remove the special handling of efi/ on x86. There's
no need for the resulting object file to be passed in any special
order to the linker.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2022-03-10 18:47:55 +00:00
Andrew Cooper 7f5b2448bd x86/kexec: Fix kexec-reboot with CET active
The kexec_reloc() asm has an indirect jump to relocate onto the identity
trampoline.  While we clear CET in machine_crash_shutdown(), we fail to clear
CET for the non-crash path.  This in turn highlights that the same is true of
resetting the CPUID masking/faulting.

Move both pieces of logic from machine_crash_shutdown() to machine_kexec(),
the latter being common for all kexec transitions.  Adjust the condition for
CET being considered active to check in CR4, which is simpler and more robust.

Fixes: 311434bfc9 ("x86/setup: Rework MSR_S_CET handling for CET-IBT")
Fixes: b60ab42db2 ("x86/shstk: Activate Supervisor Shadow Stacks")
Fixes: 5ab9564c6f ("x86/cpu: Context switch cpuid masks and faulting state in context_switch()")
Reported-by: David Vrabel <dvrabel@amazon.co.uk>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: David Vrabel <dvrabel@amazon.co.uk>
2022-03-10 18:47:55 +00:00
Bjoern Doebel 5142dc5c25 livepatch: resolve old address before function verification
When verifying that a livepatch can be applied, we may as well want to
inspect the target function to be patched. To do so, we need to resolve
this function's address before running the arch-specific
livepatch_verify hook.

Signed-off-by: Bjoern Doebel <doebel@amazon.de>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
2022-03-09 16:22:03 +01:00
Roger Pau Monné b4f2116060 vpci/msix: fix PBA accesses
Map the PBA in order to access it from the MSI-X read and write
handlers. Note that previously the handlers would pass the physical
host address into the {read,write}{l,q} handlers, which is wrong as
those expect a linear address.

Map the PBA using ioremap when the first access is performed. Note
that 32bit arches might want to abstract the call to ioremap into a
vPCI arch handler, so they can use a fixmap range to map the PBA.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Alex Olson <Alex.Olson@starlab.io>
2022-03-09 16:21:01 +01:00
Andrew Cooper 8d03080d2a x86/spec-ctrl: Cease using thunk=lfence on AMD
AMD have updated their Spectre v2 guidance, and lfence/jmp is no longer
considered safe.  AMD are recommending using retpoline everywhere.

Retpoline is incompatible with CET.  All CET-capable hardware has efficient
IBRS (specifically, not something retrofitted in microcode), so use IBRS (and
STIBP for consistency sake).

This is a logical change on AMD, but not on Intel as the default calculations
would end up with these settings anyway.  Leave behind a message if IBRS is
found to be missing.

Also update the default heuristics to never select THUNK_LFENCE.  This causes
AMD CPUs to change their default to retpoline.

Also update the printed message to include the AMD MSR_SPEC_CTRL settings, and
STIBP now that we set it for consistency sake.

This is part of XSA-398 / CVE-2021-26401.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-08 16:38:02 +00:00
Bertrand Marquis c0a56ea0fd xen/arm: Allow to discover and use SMCCC_ARCH_WORKAROUND_3
Allow guest to discover whether or not SMCCC_ARCH_WORKAROUND_3 is
supported and create a fastpath in the code to handle guests request to
do the workaround.

The function SMCCC_ARCH_WORKAROUND_3 will be called by the guest for
flushing the branch history. So we want the handling to be as fast as
possible.

As the mitigation is applied on every guest exit, we can check for the
call before saving all context and return very early.

This is part of XSA-398 / CVE-2022-23960.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Julien Grall <julien@xen.org>
2022-03-08 16:38:02 +00:00
Rahul Singh 62c91eb66a xen/arm: Add Spectre BHB handling
This commit is adding Spectre BHB handling to Xen on Arm.
The commit is introducing new alternative code to be executed during
exception entry:
- SMCC workaround 3 call
- loop workaround (with 8, 24 or 32 iterations)
- use of new clearbhb instruction

Cpuerrata is modified by this patch to apply the required workaround for
CPU affected by Spectre BHB when CONFIG_ARM64_HARDEN_BRANCH_PREDICTOR is
enabled.

To do this the system previously used to apply smcc workaround 1 is
reused and new alternative code to be copied in the exception handler is
introduced.

To define the type of workaround required by a processor, 4 new cpu
capabilities are introduced (for each number of loop and for smcc
workaround 3).

When a processor is affected, enable_spectre_bhb_workaround is called
and if the processor does not have CSV2 set to 3 or ECBHB feature (which
would mean that the processor is doing what is required in hardware),
the proper code is enabled at exception entry.

In the case where workaround 3 is not supported by the firmware, we
enable workaround 1 when possible as it will also mitigate Spectre BHB
on systems without CSV2.

This is part of XSA-398 / CVE-2022-23960.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Julien Grall <julien@xen.org>
2022-03-08 16:38:02 +00:00
Bertrand Marquis 4b68d12d98 xen/arm: Add ECBHB and CLEARBHB ID fields
Introduce ID coprocessor register ID_AA64ISAR2_EL1.
Add definitions in cpufeature and sysregs of ECBHB field in mmfr1 and
CLEARBHB in isar2 ID coprocessor registers.

This is part of XSA-398 / CVE-2022-23960.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <julien@xen.org>
2022-03-08 16:38:02 +00:00
Bertrand Marquis 599616d70e xen/arm: move errata CSV2 check earlier
CSV2 availability check is done after printing to the user that
workaround 1 will be used. Move the check before to prevent saying to the
user that workaround 1 is used when it is not because it is not needed.
This will also allow to reuse install_bp_hardening_vec function for
other use cases.

Code previously returning "true", now returns "0" to conform to
enable_smccc_arch_workaround_1 returning an int and surrounding code
doing a "return 0" if workaround is not needed.

This is part of XSA-398 / CVE-2022-23960.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Julien Grall <julien@xen.org>
2022-03-08 16:38:02 +00:00
Bertrand Marquis 35d1b85a6b xen/arm: Introduce new Arm processors
Add some new processor identifiers in processor.h and sync Xen
definitions with status of Linux 5.17 (declared in
arch/arm64/include/asm/cputype.h).

This is part of XSA-398 / CVE-2022-23960.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <julien@xen.org>
2022-03-08 16:38:02 +00:00
Andrew Cooper 9d4a44380d x86/cet: Force -fno-jump-tables for CET-IBT
Both GCC and Clang have a (mis)feature where, even with
-fcf-protection=branch, jump tables are created using a notrack jump rather
than using endbr's in each case statement.

This is incompatible with the safety properties we want in Xen, and enforced
by not setting MSR_S_CET.NOTRACK_EN.  The consequence is a fatal #CP[endbr].

-fno-jump-tables is generally active as a side effect of
CONFIG_INDIRECT_THUNK (retpoline), but as of c/s 95d9ab4614 ("x86/Kconfig:
introduce option to select retpoline usage"), we explicitly support turning
retpoline off.

Fixes: 3667f7f8f7 ("x86: Introduce support for CET-IBT")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-07 14:13:01 +00:00
Lasse Collin 4cb8d7a067 xz: fix spelling in comments
uncompressible -> incompressible
non-splitted -> non-split

Link: https://lore.kernel.org/r/20211010213145.17462-6-xiang@kernel.org
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0a434e0a2c9f
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:10:03 +01:00
Lasse Collin 9a46de64b8 xz: move s->lzma.len = 0 initialization to lzma_reset()
It's a more logical place even if the resetting needs to be done
only once per LZMA2 stream (if lzma_reset() called in the middle
of an LZMA2 stream, .len will already be 0).

Link: https://lore.kernel.org/r/20211010213145.17462-4-xiang@kernel.org
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git a98a25408b0e
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:09:26 +01:00
Lasse Collin 0a21660515 xz: validate the value before assigning it to an enum variable
This might matter, for example, if the underlying type of enum xz_check
was a signed char. In such a case the validation wouldn't have caught an
unsupported header. I don't know if this problem can occur in the kernel
on any arch but it's still good to fix it because some people might copy
the XZ code to their own projects from Linux instead of the upstream
XZ Embedded repository.

This change may increase the code size by a few bytes. An alternative
would have been to use an unsigned int instead of enum xz_check but
using an enumeration looks cleaner.

Link: https://lore.kernel.org/r/20211010213145.17462-3-xiang@kernel.org
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 4f8d7abaa413
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:08:54 +01:00
Lasse Collin 10454f381f xz: avoid overlapping memcpy() with invalid input with in-place decompression
From: Lasse Collin <lasse.collin@tukaani.org>

With valid files, the safety margin described in lib/decompress_unxz.c
ensures that these buffers cannot overlap. But if the uncompressed size
of the input is larger than the caller thought, which is possible when
the input file is invalid/corrupt, the buffers can overlap. Obviously
the result will then be garbage (and usually the decoder will return
an error too) but no other harm will happen when such an over-run occurs.

This change only affects uncompressed LZMA2 chunks and so this
should have no effect on performance.

Link: https://lore.kernel.org/r/20211010213145.17462-2-xiang@kernel.org
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 83d3c4f22a36
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:08:08 +01:00
Zhen Lei bbd9f36bca decompressors: fix spelling mistakes
Fix some spelling mistakes in comments:
sentinal ==> sentinel
compresed ==> compressed
immediatelly ==> immediately
dervied ==> derived
splitted ==> split
nore ==> not
independed ==> independent
asumed ==> assumed

Link: https://lkml.kernel.org/r/20210604085656.12257-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 05911c5d964
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:07:19 +01:00
Lasse Collin 22d5d1c0d1 xz: fix XZ_DYNALLOC to avoid useless memory reallocations
s->dict.allocated was initialized to 0 but never set after a successful
allocation, thus the code always thought that the dictionary buffer has
to be reallocated.

Link: http://lkml.kernel.org/r/20191104185107.3b6330df@tukaani.org
Reported-by: Yu Sun <yusun2@cisco.com>
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Acked-by: Daniel Walker <danielwa@cisco.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8e20ba2e53fc
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:06:31 +01:00
Lasse Collin c9875a8cce xz: add fall-through comments to a switch statement
It's good style. I was also told that GCC 7 is more strict and might
give a warning when such comments are missing.

Suggested-by: Andrei Borzenkov <arvidjaar@gmail.com>
Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 5a244f48ecbb
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-07 09:05:44 +01:00
Jan Beulich a9c8432e2a x86/tboot: adjust Kconfig default
We shouldn't include unsupported code by default, with not even a means
for its building to be disabled. Convert the dependency from merely
affecting the prompt's visibility to a real one.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Daniel P. Smith <dpsmith@apertussolutions.com>
2022-03-07 08:59:46 +01:00
Jan Beulich 1145d94c73 x86: also discard .fini_array in linker script
This simply parallels .dtors. Both section types can reference
.text.exit, which requires them to be discarded together with that one.
Compilers, depending on their findings during the configure phase, may
elect to use either model. While .{init,fini}_array look to be
preferred, cross compilers apparently have this guessed, likely
resulting in a fallback to .{c,d}tors. Hence we need to support both
sets.

Fixes: 4b7fd8153d ("x86: fold sections in final binaries")
Reported-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2022-03-04 10:49:22 +01:00
Jan Beulich 248496f890 x86emul: correct a few scalar insn comments
Truly scalar insns (i.e. not VBROADCASTS{S,D}) only every act on
%xmm<N>. Adjust comments accordingly.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-04 09:30:07 +01:00
Jan Beulich ccb6f9a558 x86emul/test: correct VRNDSCALES{S,D} entries in predicates test
While benign (because only the decoder is exercised here, whereas a
wrong EVEX.W would cause an exception only during actual emulation),
let's still have correct information in the table entries.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-04 09:29:42 +01:00
Jan Beulich b7a7e346c7 x86: drop use of CONSTRUCTORS from linker script
Current binutils document this for use by a.out only. Plus we deal with
.ctors and alike sections elsewhere in the script anyway.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
2022-03-04 09:29:10 +01:00
Jan Beulich dc762a509d x86/time: add CF-clobber annotations
With bed9ae54df ("x86/time: switch platform timer hooks to altcall")
in place we can further arrange for ENDBR removal from the functions no
longer subject to indirect calls. Note that plt_tsc is adjusted as well,
despite presently not holding any pointer eligible for ENDBR removal.
This is just to be on the safe side going forward.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-04 09:28:09 +01:00
Jan Beulich e1cafab334 build: export potentially overridden tool chain components
When overriding the tool chain via CROSS_COMPILE, the resulting
components need to be made available to, in particular (but not limited
to) the check-endbr.sh script. Note that we don't allow overriding
ADDR2LINE yet; this would first require additions to some config/*.mk
before it would make sense to export the resulting variable as well.

The lack of NM exporting was apparently not a problem so far, but add it
at this occasion as well - we're using the tool, after all.

Fixes: 4d037425dc ("x86: Build check for embedded endbr64 instructions")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-04 09:27:08 +01:00
Anthony PERARD d58a509e01 build,x86: remove the need for build32.mk
Rework "arch/x86/boot/Makefile" to allow it to build both file
"cmdline.S" and "reloc.S" without "build32.mk".

These will now use the main rules for "%.o: %.c", and thus generate a
dependency file. (We will not need to track the dependency manually
anymore.)

But for that, we need to override the main CFLAGS to do a 32bit build.
We introduce XEN_TREEWIDE_CFLAGS which can be reused in boot/Makefile,
and avoid the need to reparse Config.mk with a different value for
XEN_TARGET_ARCH. From this new $(XEN_TREEWIDE_CFLAGS), we only need to
change -m64 to have the 32bit flags. Then those are applied only to
"cmdline.o" and "reloc.o".

Specifically apply the rule "%.S: %.bin" to both cmdline.S and reloc.S
to avoid make trying to regenerate other %.S files with it.

There is no change expected to the resulting "cmdline.S" and
"reloc.S", only the *.o file changes as their symbol for FILE goes
from "cmdline.c" to "arch/x86//cmdline.c". (No idea why "boot" is
missing from the string.) (I've only check with GCC, not clang.)

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-04 09:25:39 +01:00
Julien Grall 1f410b0c74 xen/arm: mm: Encode existing constraints of the memory layout
The boot code expects the regions XEN_VIRT_START, FIXMAP_ADDR(0),
BOOT_FDT_VIRT_START to use the same 0th (arm64 only) and 1st slot.

Add some BUILD_BUG_ON() to confirm that. This is helpful if one wants
to re-order the memory layout.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-03-03 20:15:14 +00:00
Michal Orzel b692523faf xen/arm: gic: Introduce GIC_PRI_{IRQ/IPI}_ALL
Introduce macros GIC_PRI_IRQ_ALL and GIC_PRI_IPI_ALL to be used in all
the places where we want to set default priority for all the offsets
in interrupt priority register. This will improve readability and
allow to get rid of introducing variables just to store this value.

Take the opportunity to mark GIC_PRI_{IRQ/IPI} as unsigned values
to suppress static analyzer warnings as they are used in expressions
exceeding integer range (shifting into signed bit). Modify also other
priority related macros to be coherent.

Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2022-03-03 19:53:41 +00:00
Andrew Cooper 3e56754b08 xen/cet: Fix __initconst_cf_clobber
The linker script collecting .init.rodata.* ahead of .init.rodata.cf_clobber
accidentally causes __initconst_cf_clobber to be a no-op.

Rearrange the linker script to unbreak this.

The IOMMU adjust_irq_affinities() hooks currently violate the safety
requirement for being cf_clobber, by also being plain __initcall()'s.

Consolidate to a single initcall using the iommu_adjust_irq_affinities()
wrapper (satisfying the cf_clobber safety requirement by using iommu_call()
under the hood), and also removes the dubious property that we'd call into
both vendors IOMMU drivers on boot, relying on the for_each_*() loops to be
empty for safety.

With this fixed, an all-enabled build of Xen has 1681 endbr64's in .text with
382 (23%) being clobbered during boot.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-03 11:21:35 +00:00
Jan Beulich 4b7fd8153d x86: fold sections in final binaries
Especially when linking a PE binary (xen.efi), standalone output
sections are expensive: Often the linker will align the subsequent one
on the section alignment boundary (2Mb) when the linker script doesn't
otherwise place it. (I haven't been able to derive from observed
behavior under what conditions it would not do so.)

With gcov enabled (and with gcc11) I'm observing enough sections that,
as of quite recently, the resulting image doesn't fit in 16Mb anymore,
failing the final ASSERT() in the linker script. (That assertion is
slated to go away, but that's a separate change.)

Any destructor related sections can be discarded, as we never "exit"
the hypervisor. This includes .text.exit, which is referenced from
.dtors.*. Constructor related sections need to all be taken care of, not
just those with historically used names: .ctors.* and .text.startup is
what gcc11 populates. While there re-arrange ordering / sorting to match
that used by the linker provided scripts.

Finally, for xen.efi only, also discard .note.gnu.*. These are
meaningless in a PE binary. Quite likely, while not meaningless there,
the section is also of no use in ELF, but keep it there for now.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2022-03-02 09:29:55 +01:00
Jan Beulich 97b80c7881 x86/altcall: silence undue warning
Suitable compiler options are passed only when the actual feature
(XEN_IBT) is enabled, not when merely the compiler capability was found
to be available.

Fixes: 12e3410e07 ("x86/altcall: Check and optimise altcall targets")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-02 09:28:51 +01:00
Jan Beulich da5827fff3 docs: correct "gnttab=" documented default
Defaults differ for Arm and x86, not the least because of v2 not even
being security supported on Arm.

Also drop a bogus sentence from gnttab_max_maptrack_frames, which was
presumably mistakenly cloned from gnttab_max_frames (albeit even there
what is being said is neither very precise nor very useful imo).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
2022-03-02 09:28:06 +01:00
Juergen Gross 5e326b6169 docs: document patch rules
Add a document to describe the rules for sending a proper patch.

As it contains all the information already being present in
docs/process/tags.pandoc remove that file.

The "Reviewed-by:" and "Acked-by:" tags are expanded to allow an
optional restriction of the tag.

A new tag "Origin:" is added to tag patches taken from another project.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
2022-03-02 09:27:19 +01:00
Julien Grall faecea18d2 xen/arm32: head: Don't set r12 and update the documentation
Since commit 54c4ae18d1 ("xen/arm32: head: Rework and document
launch()"), the boot code is setting r12 but not read it.

So remove the two instructions setting r12 and update the documentation
to show r12 has no specific purpose.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-03-01 20:01:12 +00:00
Julien Grall 767bae66e1 xen/arm64: head: Mark the end of subroutines with ENDPROC (take two)
Commit 13c03002c5 ("xen/arm64: head: Mark the end of subroutines
with ENDPROC") intended to mark all the subroutines with ENDPROC.

Unfortunately, I missed fail(), switch_ttbr() and init_uart(). Add
ENDPROC for the benefits of static analysis tools and the reader.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-03-01 19:59:28 +00:00
Julien Grall 84c3eb3a9c xen/arm32: head: Mark the end of subroutines with ENDPROC (take two)
Commit 2ac705a59e ("xen/arm32: head: Mark the end of subroutines
with ENDPROC") intended to mark all the subroutines with ENDPROC.

Unfortunately, I missed fail(), switch_ttbr(), init_uart() and
__lookup_processor_type(). Add ENDPROC for the benefits of
static analysis tools and the reader.

Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
2022-03-01 19:56:24 +00:00
Julien Grall 0c18fb7632 xen/arm: Remove unused BOOT_RELOC_VIRT_START
We stopped relocating Xen since commit f60658c6ae "xen/arm: Stop
relocating Xen".

At the same time, update the memory layout description.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Reviewed-by: Michal Orzel <michal.orzel@arm.com>
2022-03-01 19:54:27 +00:00
Andrew Cooper 6e3f36387d x86/spec-ctrl: Disable retpolines with CET-IBT
CET-IBT depend on executing indirect branches for protections to apply.
Extend the clobber for CET-SS to all of CET.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
2022-03-01 12:34:46 +00:00
Jan Beulich e0a514d2f4 x86/CPUID: correct FEATURESET_7d2 comment
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
2022-03-01 10:03:19 +01:00