Commit Graph

56 Commits

Author SHA1 Message Date
Kairui Song 7ea0ebd4b7 arm64: kexec_file: add crash dump support
Upstream: 3751e728cef2908c15974a5ae44627fd41ef3362
Link: 40e94ab32e

commit 3751e728cef2908c15974a5ae44627fd41ef3362
Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
Date:   Mon Dec 16 11:12:47 2019 +0900

    arm64: kexec_file: add crash dump support

    Enabling crash dump (kdump) includes
    * prepare contents of ELF header of a core dump file, /proc/vmcore,
      using crash_prepare_elf64_headers(), and
    * add two device tree properties, "linux,usable-memory-range" and
      "linux,elfcorehdr", which represent respectively a memory range
      to be used by crash dump kernel and the header's location

    Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
    Cc: Catalin Marinas <catalin.marinas@arm.com>
    Cc: Will Deacon <will.deacon@arm.com>
    Reviewed-by: James Morse <james.morse@arm.com>
    Tested-and-reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
    Signed-off-by: Will Deacon <will@kernel.org>

Signed-off-by: Kairui Song <kasong@tencent.com>
2022-06-06 14:15:40 +08:00
Kairui Song c7b1305ab6 arm64: kdump: remove dependency on arm64_dma32_phys_limit
From: Yi Li <adamliyi@msn.com>
Link: 696027f109

The patch b2da6ad294
(arm64: kdump: reimplement crashkernel=X) depends on commit 1a8e1cef7603
("arm64: use both ZONE_DMA and ZONE_DMA32").

Commit 1a8e1cef7603 is not ported to 5.4 kernel. So use arm64_dma_phys_limit.

Signed-off-by: Kairui Song <kasong@tencent.com>
2022-06-06 14:05:55 +08:00
Kairui Song 652208f695 arm64: kdump: reimplement crashkernel=X
From: Chen Zhou <chenzhou10@huawei.com>
Link: https://lkml.org/lkml/2021/1/30/53
Link: 70e586365f

There are following issues in arm64 kdump:
1. We use crashkernel=X to reserve crashkernel below 4G, which
will fail when there is no enough low memory.
2. If reserving crashkernel above 4G, in this case, crash dump
kernel will boot failure because there is no low memory available
for allocation.
3. Since commit 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32"),
if the memory reserved for crash dump kernel falled in ZONE_DMA32,
the devices in crash dump kernel need to use ZONE_DMA will alloc
fail.

To solve these issues, change the behavior of crashkernel=X and
introduce crashkernel=X,[high,low]. crashkernel=X tries low allocation
in DMA zone or DMA32 zone if CONFIG_ZONE_DMA is disabled, and fall back
to high allocation if it fails.
We can also use "crashkernel=X,high" to select a region above DMA zone,
which also tries to allocate at least 256M in DMA zone automatically
(or the DMA32 zone if CONFIG_ZONE_DMA is disabled).
"crashkernel=Y,low" can be used to allocate specified size low memory.

Another minor change, there may be two regions reserved for crash
dump kernel, in order to distinct from the high region and make no
effect to the use of existing kexec-tools, rename the low region as
"Crash kernel (low)".

Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Tested-by: John Donnelly <John.p.donnelly@oracle.com>
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Kairui Song <kasong@tencent.com>
2022-06-06 13:51:29 +08:00
Kairui Song afb152c649 arm64: kdump: introduce some macroes for crash kernel reservation
From: Chen Zhou <chenzhou10@huawei.com>
Link: https://lkml.org/lkml/2021/1/30/53
Link: 667118f8c1

Introduce macro CRASH_ALIGN for alignment, macro CRASH_ADDR_LOW_MAX
for upper bound of low crash memory, macro CRASH_ADDR_HIGH_MAX for
upper bound of high crash memory, use macroes instead.

Besides, keep consistent with x86, use CRASH_ALIGN as the lower bound
of crash kernel reservation.

Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Tested-by: John Donnelly <John.p.donnelly@oracle.com>
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: Kairui Song <kasong@tencent.com>
2022-06-06 13:51:07 +08:00
Jianping Liu 6482dd88ba backport from bbdbc11804ff0b4130e7550113b452e96a74d16e
arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfo

TCR_EL1.TxSZ, which controls the VA space size, is configured by a
single kernel image to support either 48-bit or 52-bit VA space.

If the ARMv8.2-LVA optional feature is present and we are running
with a 64KB page size, then it is possible to use 52-bits of address
space for both userspace and kernel addresses. However, any kernel
binary that supports 52-bit must also be able to fall back to 48-bit
at early boot time if the hardware feature is not present.

Since TCR_EL1.T1SZ indicates the size of the memory region addressed by
TTBR1_EL1, export the same in vmcoreinfo. User-space utilities like
makedumpfile and crash-utility need to read this value from vmcoreinfo
for determining if a virtual address lies in the linear map range.

While at it also add documentation for TCR_EL1.T1SZ variable being
added to vmcoreinfo.

It indicates the size offset of the memory region addressed by
TTBR1_EL1.
2022-04-25 19:57:46 +08:00
Bin Lai a9bcce0fce iommu/phytium: fix PLX acs bug on phytium platform
Phytium platform doesn't support PLX acs feature, it would affect
the device passthrough fucntion. So phytium provide this patch to
avoid this issue.

Signed-off-by: Bin Lai <robinlai@tencent.com>
2022-04-08 10:09:19 +08:00
Bin Lai 56167c1782 arm64/phytium-2500: make sure that there is at least one online cpu on each node for kdump
If the storage device is located on socket1, the interrupt cann't
be handled on socket0 for phytium-2500. So we must guarantee that
there is at least one online cpu on each node, otherwise the kdump
may not work on phytium-2500 platform.

Signed-off-by: Bin Lai <robinlai@tencent.com>
2022-04-08 10:09:19 +08:00
Fuhai Wang f454797b67 ampere/arm64: Work around Ampere Altra erratum #82288 PCIE_65
Altra's PCIe controller may generate incorrect addresses when receiving
writes from the CPU with a discontiguous set of byte enables. Attempt to
work around this by handing out Device-nGnRE maps instead of Normal
Non-cacheable maps for PCIe memory areas.

Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
2021-07-12 08:57:22 +00:00
D Scott Phillips e55f6ef6b7 ampere/arm64: Add a fixup handler for alignment faults in aarch64 code
A later patch will hand out Device memory in some cases to code
which expects a Normal memory type, as an errata workaround.
Unaligned accesses to Device memory will fault though, so here we
add a fixup handler to emulate faulting accesses, at a performance
penalty.

Many of the instructions in the Loads and Stores group are supported,
but these groups are not handled here:

 * Advanced SIMD load/store multiple structures
 * Advanced SIMD load/store multiple structures (post-indexed)
 * Advanced SIMD load/store single structure
 * Advanced SIMD load/store single structure (post-indexed)
 * Load/store memory tags
 * Load/store exclusive
 * LDAPR/STLR (unscaled immediate)
 * Load register (literal) [cannot Alignment fault]
 * Load/store register (unprivileged)
 * Atomic memory operations
 * Load/store register (pac)

Instruction implementations are translated from the Exploration tools'
ASL specifications.

Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com>
2021-07-12 08:57:22 +00:00
Nathan Chancellor 0408f6dcbe arm64: alternatives: Move length validation in alternative_{insn, endif}
commit 22315a2296f4c251fa92aec45fbbae37e9301b6c upstream.

After commit 2decad92f473 ("arm64: mte: Ensure TIF_MTE_ASYNC_FAULT is
set atomically"), LLVM's integrated assembler fails to build entry.S:

<instantiation>:5:7: error: expected assembly-time absolute expression
 .org . - (664b-663b) + (662b-661b)
      ^
<instantiation>:6:7: error: expected assembly-time absolute expression
 .org . - (662b-661b) + (664b-663b)
      ^

The root cause is LLVM's assembler has a one-pass design, meaning it
cannot figure out these instruction lengths when the .org directive is
outside of the subsection that they are in, which was changed by the
.arch_extension directive added in the above commit.

Apply the same fix from commit 966a0acce2fc ("arm64/alternatives: move
length validation inside the subsection") to the alternative_endif
macro, shuffling the .org directives so that the length validation
happen will always happen in the same subsections. alternative_insn has
not shown any issue yet but it appears that it could have the same issue
in the future so just preemptively change it.

Fixes: f7b93d42945c ("arm64/alternatives: use subsections for replacement sequences")
Cc: <stable@vger.kernel.org> # 5.8.x
Link: https://github.com/ClangBuiltLinux/linux/issues/1347
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20210414000803.662534-1-nathan@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-20 16:07:11 +08:00
Peter Collingbourne 7a37e1ab0f arm64: fix inline asm in load_unaligned_zeropad()
commit 185f2e5f51c2029efd9dd26cceb968a44fe053c6 upstream.

The inline asm's addr operand is marked as input-only, however in
the case where an exception is taken it may be modified by the BIC
instruction on the exception path. Fix the problem by using a temporary
register as the destination register for the BIC instruction.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Cc: stable@vger.kernel.org
Link: https://linux-review.googlesource.com/id/I84538c8a2307d567b4f45bb20b715451005f9617
Link: https://lore.kernel.org/r/20210401165110.3952103-1-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-20 16:07:11 +08:00
Suzuki K Poulose 72d5b6bb67 KVM: arm64: Disable guest access to trace filter controls
[ Upstream commit a354a64d91eec3e0f8ef0eed575b480fd75b999c ]

Disable guest access to the Trace Filter control registers.
We do not advertise the Trace filter feature to the guest
(ID_AA64DFR0_EL1: TRACE_FILT is cleared) already, but the guest
can still access the TRFCR_EL1 unless we trap it.

This will also make sure that the guest cannot fiddle with
the filtering controls set by a nvhe host.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210323120647.454211-3-suzuki.poulose@arm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-20 16:07:05 +08:00
Suzuki K Poulose a8b3601db6 KVM: arm64: nvhe: Save the SPE context early
commit b96b0c5de685df82019e16826a282d53d86d112c upstream

The nVHE KVM hyp drains and disables the SPE buffer, before
entering the guest, as the EL1&0 translation regime
is going to be loaded with that of the guest.

But this operation is performed way too late, because :
 - The owning translation regime of the SPE buffer
   is transferred to EL2. (MDCR_EL2_E2PB == 0)
 - The guest Stage1 is loaded.

Thus the flush could use the host EL1 virtual address,
but use the EL2 translations instead of host EL1, for writing
out any cached data.

Fix this by moving the SPE buffer handling early enough.
The restore path is doing the right thing.

Cc: stable@vger.kernel.org # v5.4-
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:53:13 +08:00
Marc Zyngier 5c734c9d32 KVM: arm64: Ensure I-cache isolation between vcpus of a same VM
Commit 01dc9262ff5797b675c32c0c6bc682777d23de05 upstream.

It recently became apparent that the ARMv8 architecture has interesting
rules regarding attributes being used when fetching instructions
if the MMU is off at Stage-1.

In this situation, the CPU is allowed to fetch from the PoC and
allocate into the I-cache (unless the memory is mapped with
the XN attribute at Stage-2).

If we transpose this to vcpus sharing a single physical CPU,
it is possible for a vcpu running with its MMU off to influence
another vcpu running with its MMU on, as the latter is expected to
fetch from the PoU (and self-patching code doesn't flush below that
level).

In order to solve this, reuse the vcpu-private TLB invalidation
code to apply the same policy to the I-cache, nuking it every time
the vcpu runs on a physical CPU that ran another vcpu of the same
VM in the past.

This involve renaming __kvm_tlb_flush_local_vmid() to
__kvm_flush_cpu_context(), and inserting a local i-cache invalidation
there.

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210303164505.68492-1-maz@kernel.org
[maz: added 32bit ARM support]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:53:12 +08:00
Ard Biesheuvel 7a7d5607fa arm64: mm: use a 48-bit ID map when possible on 52-bit VA builds
[ Upstream commit 7ba8f2b2d652cd8d8a2ab61f4be66973e70f9f88 ]

52-bit VA kernels can run on hardware that is only 48-bit capable, but
configure the ID map as 52-bit by default. This was not a problem until
recently, because the special T0SZ value for a 52-bit VA space was never
programmed into the TCR register anwyay, and because a 52-bit ID map
happens to use the same number of translation levels as a 48-bit one.

This behavior was changed by commit 1401bef703a4 ("arm64: mm: Always update
TCR_EL1 from __cpu_set_tcr_t0sz()"), which causes the unsupported T0SZ
value for a 52-bit VA to be programmed into TCR_EL1. While some hardware
simply ignores this, Mark reports that Amberwing systems choke on this,
resulting in a broken boot. But even before that commit, the unsupported
idmap_t0sz value was exposed to KVM and used to program TCR_EL2 incorrectly
as well.

Given that we already have to deal with address spaces being either 48-bit
or 52-bit in size, the cleanest approach seems to be to simply default to
a 48-bit VA ID map, and only switch to a 52-bit one if the placement of the
kernel in DRAM requires it. This is guaranteed not to happen unless the
system is actually 52-bit VA capable.

Fixes: 90ec95cda91a ("arm64: mm: Introduce VA_BITS_MIN")
Reported-by: Mark Salter <msalter@redhat.com>
Link: http://lore.kernel.org/r/20210310003216.410037-1-msalter@redhat.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210310171515.416643-2-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:53:11 +08:00
Andrey Konovalov 843477189c arm64: kasan: fix page_alloc tagging with DEBUG_VIRTUAL
commit 86c83365ab76e4b43cedd3ce07a07d32a4dc79ba upstream.

When CONFIG_DEBUG_VIRTUAL is enabled, the default page_to_virt() macro
implementation from include/linux/mm.h is used. That definition doesn't
account for KASAN tags, which leads to no tags on page_alloc allocations.

Provide an arm64-specific definition for page_to_virt() when
CONFIG_DEBUG_VIRTUAL is enabled that takes care of KASAN tags.

Fixes: 2813b9c02962 ("kasan, mm, arm64: tag non slab memory allocated via pagealloc")
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/4b55b35202706223d3118230701c6a59749d9b72.1615219501.git.andreyknvl@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:53:05 +08:00
Catalin Marinas ac7f207866 arm64: Do not pass tagged addresses to __is_lm_address()
commit 91cb2c8b072e00632adf463b78b44f123d46a0fa upstream.

Commit 519ea6f1c82f ("arm64: Fix kernel address detection of
__is_lm_address()") fixed the incorrect validation of addresses below
PAGE_OFFSET. However, it no longer allowed tagged addresses to be passed
to virt_addr_valid().

Fix this by explicitly resetting the pointer tag prior to invoking
__is_lm_address(). This is consistent with the __lm_to_phys() macro.

Fixes: 519ea6f1c82f ("arm64: Fix kernel address detection of __is_lm_address()")
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Cc: <stable@vger.kernel.org> # 5.4.x
Cc: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210201190634.22942-2-catalin.marinas@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:49 +08:00
Vincenzo Frascino 5671accc27 arm64: Fix kernel address detection of __is_lm_address()
commit 519ea6f1c82fcdc9842908155ae379de47818778 upstream.

Currently, the __is_lm_address() check just masks out the top 12 bits
of the address, but if they are 0, it still yields a true result.
This has as a side effect that virt_addr_valid() returns true even for
invalid virtual addresses (e.g. 0x0).

Fix the detection checking that it's actually a kernel address starting
at PAGE_OFFSET.

Fixes: 68dd8ef32162 ("arm64: memory: Fix virt_addr_valid() using __is_lm_address()")
Cc: <stable@vger.kernel.org> # 5.4.x
Cc: Will Deacon <will@kernel.org>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210126134056.45747-1-vincenzo.frascino@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:49 +08:00
Ard Biesheuvel 0f24e3c436 arm64: mm: use single quantity to represent the PA to VA translation
commit 7bc1a0f9e1765830e945669c99c59c35cf9bca82 upstream.

On arm64, the global variable memstart_addr represents the physical
address of PAGE_OFFSET, and so physical to virtual translations or
vice versa used to come down to simple additions or subtractions
involving the values of PAGE_OFFSET and memstart_addr.

When support for 52-bit virtual addressing was introduced, we had to
deal with PAGE_OFFSET potentially being outside of the region that
can be covered by the virtual range (as the 52-bit VA capable build
needs to be able to run on systems that are only 48-bit VA capable),
and for this reason, another translation was introduced, and recorded
in the global variable physvirt_offset.

However, if we go back to the original definition of memstart_addr,
i.e., the physical address of PAGE_OFFSET, it turns out that there is
no need for two separate translations: instead, we can simply subtract
the size of the unaddressable VA space from memstart_addr to make the
available physical memory appear in the 48-bit addressable VA region.

This simplifies things, but also fixes a bug on KASLR builds, which
may update memstart_addr later on in arm64_memblock_init(), but fails
to update vmemmap and physvirt_offset accordingly.

Fixes: 5383cc6efed1 ("arm64: mm: Introduce vabits_actual")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Link: https://lore.kernel.org/r/20201008153602.9467-2-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:42 +08:00
Arnd Bergmann cd7402f61d arm64: make atomic helpers __always_inline
[ Upstream commit c35a824c31834d947fb99b0c608c1b9f922b4ba0 ]

With UBSAN enabled and building with clang, there are occasionally
warnings like

WARNING: modpost: vmlinux.o(.text+0xc533ec): Section mismatch in reference from the function arch_atomic64_or() to the variable .init.data:numa_nodes_parsed
The function arch_atomic64_or() references
the variable __initdata numa_nodes_parsed.
This is often because arch_atomic64_or lacks a __initdata
annotation or the annotation of numa_nodes_parsed is wrong.

for functions that end up not being inlined as intended but operating
on __initdata variables. Mark these as __always_inline, along with
the corresponding asm-generic wrappers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210108092024.4034860-1-arnd@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:51:34 +08:00
Tuan Phan fbd4e4684a BACKPORT: Split the old READ_IMPLIES_EXEC workaround from executable
PT_GNU_STACK now that toolchains long support PT_GNU_STACK marking and
there's no need anymore to force modern programs into having all its
user mappings executable instead of only the stack and the PROT_EXEC
ones.

Disable that automatic READ_IMPLIES_EXEC forcing on x86-64 and
arm64.

Add tables documenting how READ_IMPLIES_EXEC is handled on x86-64, arm
and arm64.

This patch is needed to fix softlock up observed during stress test.

Backport from: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.8-rc1&id=ac7b34218a0021bafd1d4c11c54217b930f516b0

Cherry-pick from: d6f5dfc8aa

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Tuan Phan <tphan@amperecomputing.com>
2021-03-16 16:43:59 +08:00
Marc Zyngier 1131eaae28 KVM: arm64: Introduce handling of AArch32 TTBCR2 traps
commit ca4e514774930f30b66375a974b5edcbebaf0e7e upstream.

ARMv8.2 introduced TTBCR2, which shares TCR_EL1 with TTBCR.
Gracefully handle traps to this register when HCR_EL2.TVM is set.

Cc: stable@vger.kernel.org
Reported-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:43:32 +08:00
Will Deacon d9cf2aa080 arm64: pgtable: Ensure dirty bit is preserved across pte_wrprotect()
commit ff1712f953e27f0b0718762ec17d0adb15c9fd0b upstream.

With hardware dirty bit management, calling pte_wrprotect() on a writable,
dirty PTE will lose the dirty state and return a read-only, clean entry.

Move the logic from ptep_set_wrprotect() into pte_wrprotect() to ensure that
the dirty bit is preserved for writable entries, as this is required for
soft-dirty bit management if we enable it in the future.

Cc: <stable@vger.kernel.org>
Fixes: 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201120143557.6715-3-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:41:36 +08:00
Will Deacon 6185909417 arm64: pgtable: Fix pte_accessible()
commit 07509e10dcc77627f8b6a57381e878fe269958d3 upstream.

pte_accessible() is used by ptep_clear_flush() to figure out whether TLB
invalidation is necessary when unmapping pages for reclaim. Although our
implementation is correct according to the architecture, returning true
only for valid, young ptes in the absence of racing page-table
modifications, this is in fact flawed due to lazy invalidation of old
ptes in ptep_clear_flush_young() where we elide the expensive DSB
instruction for completing the TLB invalidation.

Rather than penalise the aging path, adjust pte_accessible() to return
true for any valid pte, even if the access flag is cleared.

Cc: <stable@vger.kernel.org>
Fixes: 76c714be0e5e ("arm64: pgtable: implement pte_accessible()")
Reported-by: Yu Zhao <yuzhao@google.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201120143557.6715-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:41:36 +08:00
Will Deacon 6a54bdcc2f arm64: errata: Fix handling of 1418040 with late CPU onlining
[ Upstream commit f969f03888b9438fdb227b6460d99ede5737326d ]

In a surprising turn of events, it transpires that CPU capabilities
configured as ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE are never set as the
result of late-onlining. Therefore our handling of erratum 1418040 does
not get activated if it is not required by any of the boot CPUs, even
though we allow late-onlining of an affected CPU.

In order to get things working again, replace the cpus_have_const_cap()
invocation with an explicit check for the current CPU using
this_cpu_has_cap().

Cc: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201106114952.10032-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:41:10 +08:00
Mark Brown fa27e4bf8d arm64: asm: Add new-style position independent function annotations
commit 35e61c77ef386555f3df1bc2057098c6997ca10b upstream.

As part of an effort to make the annotations in assembly code clearer and
more consistent new macros have been introduced, including replacements
for ENTRY() and ENDPROC().

On arm64 we have ENDPIPROC(), a custom version of ENDPROC() which is
used for code that will need to run in position independent environments
like EFI, it creates an alias for the function with the prefix __pi_ and
then emits the standard ENDPROC. Add new-style macros to replace this
which expand to the standard SYM_FUNC_*() and SYM_FUNC_ALIAS_*(),
resulting in the same object code. These are added in linkage.h for
consistency with where the generic assembler code has its macros.

Signed-off-by: Mark Brown <broonie@kernel.org>
[will: Rename 'WEAK' macro, use ';' instead of ASM_NL, deprecate ENDPIPROC]
Signed-off-by: Will Deacon <will@kernel.org>
Cc: Jian Cai <jiancai@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:40:17 +08:00
Marc Zyngier 8ffac2edcb KVM: arm64: Fix AArch32 handling of DBGD{CCINT,SCRext} and DBGVCR
commit 4a1c2c7f63c52ccb11770b5ae25920a6b79d3548 upstream.

The DBGD{CCINT,SCRext} and DBGVCR register entries in the cp14 array
are missing their target register, resulting in all accesses being
targetted at the guard sysreg (indexed by __INVALID_SYSREG__).

Point the emulation code at the actual register entries.

Fixes: bdfb4b389c8d ("arm64: KVM: add trap handlers for AArch32 debug registers")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201029172409.2768336-1-maz@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:40:15 +08:00
Zhengyuan Liu a27382ff61 arm64/mm: return cpu_all_mask when node is NUMA_NO_NODE
[ Upstream commit a194c5f2d2b3a05428805146afcabe5140b5d378 ]

The @node passed to cpumask_of_node() can be NUMA_NO_NODE, in that
case it will trigger the following WARN_ON(node >= nr_node_ids) due to
mismatched data types of @node and @nr_node_ids. Actually we should
return cpu_all_mask just like most other architectures do if passed
NUMA_NO_NODE.

Also add a similar check to the inline cpumask_of_node() in numa.h.

Signed-off-by: Zhengyuan Liu <liuzhengyuan@tj.kylinos.cn>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Link: https://lore.kernel.org/r/20200921023936.21846-1-liuzhengyuan@tj.kylinos.cn
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:39:48 +08:00
Marc Zyngier b29cdeaf5f KVM: arm64: Assume write fault on S1PTW permission fault on instruction fetch
commit c4ad98e4b72cb5be30ea282fce935248f2300e62 upstream.

KVM currently assumes that an instruction abort can never be a write.
This is in general true, except when the abort is triggered by
a S1PTW on instruction fetch that tries to update the S1 page tables
(to set AF, for example).

This can happen if the page tables have been paged out and brought
back in without seeing a direct write to them (they are thus marked
read only), and the fault handling code will make the PT executable(!)
instead of writable. The guest gets stuck forever.

In these conditions, the permission fault must be considered as
a write so that the Stage-1 update can take place. This is essentially
the I-side equivalent of the problem fixed by 60e21a0ef54c ("arm64: KVM:
Take S1 walks into account when determining S2 write faults").

Update kvm_is_write_fault() to return true on IABT+S1PTW, and introduce
kvm_vcpu_trap_is_exec_fault() that only return true when no faulting
on a S1 fault. Additionally, kvm_vcpu_dabt_iss1tw() is renamed to
kvm_vcpu_abt_iss1tw(), as the above makes it plain that it isn't
specific to data abort.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Will Deacon <will@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200915104218.1284701-2-maz@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:37:40 +08:00
James Morse 6a1958b8da KVM: arm64: Set HCR_EL2.PTW to prevent AT taking synchronous exception
commit 71a7f8cb1ca4ca7214a700b1243626759b6c11d4 upstream.

AT instructions do a translation table walk and return the result, or
the fault in PAR_EL1. KVM uses these to find the IPA when the value is
not provided by the CPU in HPFAR_EL1.

If a translation table walk causes an external abort it is taken as an
exception, even if it was due to an AT instruction. (DDI0487F.a's D5.2.11
"Synchronous faults generated by address translation instructions")

While we previously made KVM resilient to exceptions taken due to AT
instructions, the device access causes mismatched attributes, and may
occur speculatively. Prevent this, by forbidding a walk through memory
described as device at stage2. Now such AT instructions will report a
stage2 fault.

Such a fault will cause KVM to restart the guest. If the AT instructions
always walk the page tables, but guest execution uses the translation cached
in the TLB, the guest can't make forward progress until the TLB entry is
evicted. This isn't a problem, as since commit 5dcd0fdbb492 ("KVM: arm64:
Defer guest entry when an asynchronous exception is pending"), KVM will
return to the host to process IRQs allowing the rest of the system to keep
running.

Cc: stable@vger.kernel.org # <v5.3: 5dcd0fdbb492 ("KVM: arm64: Defer guest entry when an asynchronous exception is pending")
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:35:22 +08:00
James Morse 69837fb2ef KVM: arm64: Survive synchronous exceptions caused by AT instructions
commit 88a84ccccb3966bcc3f309cdb76092a9892c0260 upstream.

KVM doesn't expect any synchronous exceptions when executing, any such
exception leads to a panic(). AT instructions access the guest page
tables, and can cause a synchronous external abort to be taken.

The arm-arm is unclear on what should happen if the guest has configured
the hardware update of the access-flag, and a memory type in TCR_EL1 that
does not support atomic operations. B2.2.6 "Possible implementation
restrictions on using atomic instructions" from DDI0487F.a lists
synchronous external abort as a possible behaviour of atomic instructions
that target memory that isn't writeback cacheable, but the page table
walker may behave differently.

Make KVM robust to synchronous exceptions caused by AT instructions.
Add a get_user() style helper for AT instructions that returns -EFAULT
if an exception was generated.

While KVM's version of the exception table mixes synchronous and
asynchronous exceptions, only one of these can occur at each location.

Re-enter the guest when the AT instructions take an exception on the
assumption the guest will take the same exception. This isn't guaranteed
to make forward progress, as the AT instructions may always walk the page
tables, but guest execution may use the translation cached in the TLB.

This isn't a problem, as since commit 5dcd0fdbb492 ("KVM: arm64: Defer guest
entry when an asynchronous exception is pending"), KVM will return to the
host to process IRQs allowing the rest of the system to keep running.

Cc: stable@vger.kernel.org # <v5.3: 5dcd0fdbb492 ("KVM: arm64: Defer guest entry when an asynchronous exception is pending")
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:35:21 +08:00
James Morse ae530efd32 KVM: arm64: Add kvm_extable for vaxorcism code
commit e9ee186bb735bfc17fa81dbc9aebf268aee5b41e upstream.

KVM has a one instruction window where it will allow an SError exception
to be consumed by the hypervisor without treating it as a hypervisor bug.
This is used to consume asynchronous external abort that were caused by
the guest.

As we are about to add another location that survives unexpected exceptions,
generalise this code to make it behave like the host's extable.

KVM's version has to be mapped to EL2 to be accessible on nVHE systems.

The SError vaxorcism code is a one instruction window, so has two entries
in the extable. Because the KVM code is copied for VHE and nVHE, we end up
with four entries, half of which correspond with code that isn't mapped.

Cc: <stable@vger.kernel.org> # 5.4.x
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:35:21 +08:00
Kefeng Wang 01373d8d55 arm64: Fix __cpu_logical_map undefined issue
[ Upstream commit eaecca9e7710281be7c31d892c9f447eafd7ddd9 ]

The __cpu_logical_map undefined issue occued when the new
tegra194-cpufreq drvier building as a module.

ERROR: modpost: "__cpu_logical_map" [drivers/cpufreq/tegra194-cpufreq.ko] undefined!

The driver using cpu_logical_map() macro which will expand to
__cpu_logical_map, we can't access it in a drvier. Let's turn
cpu_logical_map() into a C wrapper and export it to fix the
build issue.

Also create a function set_cpu_logical_map(cpu, hwid) when assign
a value to cpu_logical_map(cpu).

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:34:54 +08:00
Will Deacon 96f2730fa7 KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()
commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream.

The 'flags' field of 'struct mmu_notifier_range' is used to indicate
whether invalidate_range_{start,end}() are permitted to block. In the
case of kvm_mmu_notifier_invalidate_range_start(), this field is not
forwarded on to the architecture-specific implementation of
kvm_unmap_hva_range() and therefore the backend cannot sensibly decide
whether or not to block.

Add an extra 'flags' parameter to kvm_unmap_hva_range() so that
architectures are aware as to whether or not they are permitted to block.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Message-Id: <20200811102725.7121-2-will@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:34:42 +08:00
Marc Zyngier 852f3a6051 arm64: Workaround circular dependency in pointer_auth.h
With the backport of f227e3ec3b5c ("random32: update the net random
state on interrupt and activity") and its associated fixes, the
arm64 build explodes early:

In file included from ../include/linux/smp.h:67,
                  from ../include/linux/percpu.h:7,
                  from ../include/linux/prandom.h:12,
                  from ../include/linux/random.h:118,
                  from ../arch/arm64/include/asm/pointer_auth.h:6,
                  from ../arch/arm64/include/asm/processor.h:39,
                  from ../include/linux/mutex.h:19,
                  from ../include/linux/kernfs.h:12,
                  from ../include/linux/sysfs.h:16,
                  from ../include/linux/kobject.h:20,
                  from ../include/linux/of.h:17,
                  from ../include/linux/irqdomain.h:35,
                  from ../include/linux/acpi.h:13,
                  from ../include/acpi/apei.h:9,
                  from ../include/acpi/ghes.h:5,
                  from ../include/linux/arm_sdei.h:8,
                  from ../arch/arm64/kernel/asm-offsets.c:10:
../arch/arm64/include/asm/smp.h💯29: error: field ‘ptrauth_key’ has
incomplete type

This is due to struct ptrauth_keys_kernel not being defined before
we transitively include asm/smp.h from linux/random.h.

Paper over it by moving the inclusion of linux/random.h *after* the
type has been defined.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:59 +08:00
Robin Murphy cac945aca0 arm64: csum: Fix handling of bad packets
[ Upstream commit 05fb3dbda187bbd9cc1cd0e97e5d6595af570ac6 ]

Although iph is expected to point to at least 20 bytes of valid memory,
ihl may be bogus, for example on reception of a corrupt packet. If it
happens to be less than 5, we really don't want to run away and
dereference 16GB worth of memory until it wraps back to exactly zero...

Fixes: 0e455d8e80aa ("arm64: Implement optimised IP checksum helpers")
Reported-by: guodeqing <geffrey.guo@huawei.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:32:53 +08:00
Sami Tolvanen 9fb36b8a56 arm64/alternatives: move length validation inside the subsection
[ Upstream commit 966a0acce2fca776391823381dba95c40e03c339 ]

Commit f7b93d42945c ("arm64/alternatives: use subsections for replacement
sequences") breaks LLVM's integrated assembler, because due to its
one-pass design, it cannot compute instruction sequence lengths before the
layout for the subsection has been finalized. This change fixes the build
by moving the .org directives inside the subsection, so they are processed
after the subsection layout is known.

Fixes: f7b93d42945c ("arm64/alternatives: use subsections for replacement sequences")
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1078
Link: https://lore.kernel.org/r/20200730153701.3892953-1-samitolvanen@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:32:53 +08:00
Will Deacon e554600aac arm64: compat: Ensure upper 32 bits of x0 are zero on syscall return
commit 15956689a0e60aa0c795174f3c310b60d8794235 upstream.

Although we zero the upper bits of x0 on entry to the kernel from an
AArch32 task, we do not clear them on the exception return path and can
therefore expose 64-bit sign extended syscall return values to userspace
via interfaces such as the 'perf_regs' ABI, which deal exclusively with
64-bit registers.

Explicitly clear the upper 32 bits of x0 on return from a compat system
call.

Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Keno Fischer <keno@juliacomputing.com>
Cc: Luis Machado <luis.machado@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:15 +08:00
Will Deacon 12fbfd0079 arm64: ptrace: Consistently use pseudo-singlestep exceptions
commit ac2081cdc4d99c57f219c1a6171526e0fa0a6fff upstream.

Although the arm64 single-step state machine can be fast-forwarded in
cases where we wish to generate a SIGTRAP without actually executing an
instruction, this has two major limitations outside of simply skipping
an instruction due to emulation.

1. Stepping out of a ptrace signal stop into a signal handler where
   SIGTRAP is blocked. Fast-forwarding the stepping state machine in
   this case will result in a forced SIGTRAP, with the handler reset to
   SIG_DFL.

2. The hardware implicitly fast-forwards the state machine when executing
   an SVC instruction for issuing a system call. This can interact badly
   with subsequent ptrace stops signalled during the execution of the
   system call (e.g. SYSCALL_EXIT or seccomp traps), as they may corrupt
   the stepping state by updating the PSTATE for the tracee.

Resolve both of these issues by injecting a pseudo-singlestep exception
on entry to a signal handler and also on return to userspace following a
system call.

Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Tested-by: Luis Machado <luis.machado@linaro.org>
Reported-by: Keno Fischer <keno@juliacomputing.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:15 +08:00
Will Deacon 441e35d818 arm64: ptrace: Override SPSR.SS when single-stepping is enabled
commit 3a5a4366cecc25daa300b9a9174f7fdd352b9068 upstream.

Luis reports that, when reverse debugging with GDB, single-step does not
function as expected on arm64:

  | I've noticed, under very specific conditions, that a PTRACE_SINGLESTEP
  | request by GDB won't execute the underlying instruction. As a consequence,
  | the PC doesn't move, but we return a SIGTRAP just like we would for a
  | regular successful PTRACE_SINGLESTEP request.

The underlying problem is that when the CPU register state is restored
as part of a reverse step, the SPSR.SS bit is cleared and so the hardware
single-step state can transition to the "active-pending" state, causing
an unexpected step exception to be taken immediately if a step operation
is attempted.

In hindsight, we probably shouldn't have exposed SPSR.SS in the pstate
accessible by the GPR regset, but it's a bit late for that now. Instead,
simply prevent userspace from configuring the bit to a value which is
inconsistent with the TIF_SINGLESTEP state for the task being traced.

Cc: <stable@vger.kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Keno Fischer <keno@juliacomputing.com>
Link: https://lore.kernel.org/r/1eed6d69-d53d-9657-1fc9-c089be07f98c@linaro.org
Reported-by: Luis Machado <luis.machado@linaro.org>
Tested-by: Luis Machado <luis.machado@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:32:15 +08:00
Ard Biesheuvel 6077b51dac arm64/alternatives: use subsections for replacement sequences
[ Upstream commit f7b93d42945cc71e1346dd5ae07c59061d56745e ]

When building very large kernels, the logic that emits replacement
sequences for alternatives fails when relative branches are present
in the code that is emitted into the .altinstr_replacement section
and patched in at the original site and fixed up. The reason is that
the linker will insert veneers if relative branches go out of range,
and due to the relative distance of the .altinstr_replacement from
the .text section where its branch targets usually live, veneers
may be emitted at the end of the .altinstr_replacement section, with
the relative branches in the sequence pointed at the veneers instead
of the actual target.

The alternatives patching logic will attempt to fix up the branch to
point to its original target, which will be the veneer in this case,
but given that the patch site is likely to be far away as well, it
will be out of range and so patching will fail. There are other cases
where these veneers are problematic, e.g., when the target of the
branch is in .text while the patch site is in .init.text, in which
case putting the replacement sequence inside .text may not help either.

So let's use subsections to emit the replacement code as closely as
possible to the patch site, to ensure that veneers are only likely to
be emitted if they are required at the patch site as well, in which
case they will be in range for the replacement sequence both before
and after it is transported to the patch site.

This will prevent alternative sequences in non-init code from being
released from memory after boot, but this is tolerable given that the
entire section is only 512 KB on an allyesconfig build (which weighs in
at 500+ MB for the entire Image). Also, note that modules today carry
the replacement sequences in non-init sections as well, and any of
those that target init code will be emitted into init sections after
this change.

This fixes an early crash when booting an allyesconfig kernel on a
system where any of the alternatives sequences containing relative
branches are activated at boot (e.g., ARM64_HAS_PAN on TX2)

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Dave P Martin <dave.martin@arm.com>
Link: https://lore.kernel.org/r/20200630081921.13443-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:31:48 +08:00
Marc Zyngier 744224c068 arm64: arch_timer: Allow an workaround descriptor to disable compat vdso
commit c1fbec4ac0d701f350a581941d35643d5a9cd184 upstream.

As we are about to disable the vdso for compat tasks in some circumstances,
let's allow a workaround descriptor to express exactly that.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200706163802.1836732-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:31:46 +08:00
Marc Zyngier 8abe73ee1f arm64: Introduce a way to disable the 32bit vdso
commit 97884ca8c2925d14c32188e865069f21378b4b4f upstream.

[this is a redesign rather than a backport]

We have a class of errata (grouped under the ARM64_WORKAROUND_1418040
banner) that force the trapping of counter access from 32bit EL0.

We would normally disable the whole vdso for such defect, except that
it would disable it for 64bit userspace as well, which is a shame.

Instead, add a new vdso_clock_mode, which signals that the vdso
isn't usable for compat tasks.  This gets checked in the new
vdso_clocksource_ok() helper, now provided for the 32bit vdso.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200706163802.1836732-2-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:31:46 +08:00
Alexandru Elisei 274c6aadd7 KVM: arm64: Annotate hyp NMI-related functions as __always_inline
commit 7733306bd593c737c63110175da6c35b4b8bb32c upstream.

The "inline" keyword is a hint for the compiler to inline a function.  The
functions system_uses_irq_prio_masking() and gic_write_pmr() are used by
the code running at EL2 on a non-VHE system, so mark them as
__always_inline to make sure they'll always be part of the .hyp.text
section.

This fixes the following splat when trying to run a VM:

[   47.625273] Kernel panic - not syncing: HYP panic:
[   47.625273] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006
[   47.625273] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000
[   47.625273] VCPU:0000000000000000
[   47.647261] CPU: 1 PID: 217 Comm: kvm-vcpu-0 Not tainted 5.8.0-rc1-ARCH+ #61
[   47.654508] Hardware name: Globalscale Marvell ESPRESSOBin Board (DT)
[   47.661139] Call trace:
[   47.663659]  dump_backtrace+0x0/0x1cc
[   47.667413]  show_stack+0x18/0x24
[   47.670822]  dump_stack+0xb8/0x108
[   47.674312]  panic+0x124/0x2f4
[   47.677446]  panic+0x0/0x2f4
[   47.680407] SMP: stopping secondary CPUs
[   47.684439] Kernel Offset: disabled
[   47.688018] CPU features: 0x240402,20002008
[   47.692318] Memory Limit: none
[   47.695465] ---[ end Kernel panic - not syncing: HYP panic:
[   47.695465] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006
[   47.695465] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000
[   47.695465] VCPU:0000000000000000 ]---

The instruction abort was caused by the code running at EL2 trying to fetch
an instruction which wasn't mapped in the EL2 translation tables. Using
objdump showed the two functions as separate symbols in the .text section.

Fixes: 85738e05dc38 ("arm64: kvm: Unmask PMR before entering guest")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20200618171254.1596055-1-alexandru.elisei@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:31:36 +08:00
Will Deacon b882316227 KVM: arm64: Fix definition of PAGE_HYP_DEVICE
commit 68cf617309b5f6f3a651165f49f20af1494753ae upstream.

PAGE_HYP_DEVICE is intended to encode attribute bits for an EL2 stage-1
pte mapping a device. Unfortunately, it includes PROT_DEVICE_nGnRE which
encodes attributes for EL1 stage-1 mappings such as UXN and nG, which are
RES0 for EL2, and DBM which is meaningless as TCR_EL2.HD is not set.

Fix the definition of PAGE_HYP_DEVICE so that it doesn't set RES0 bits
at EL2.

Acked-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200708162546.26176-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:31:36 +08:00
Daniel Thompson 0535ba576e arm64: cacheflush: Fix KGDB trap detection
[ Upstream commit ab8ad279ceac4fc78ae4dcf1a26326e05695e537 ]

flush_icache_range() contains a bodge to avoid issuing IPIs when the kgdb
trap handler is running because issuing IPIs is unsafe (and not needed)
in this execution context. However the current test, based on
kgdb_connected is flawed: it both over-matches and under-matches.

The over match occurs because kgdb_connected is set when gdb attaches
to the stub and remains set during normal running. This is relatively
harmelss because in almost all cases irq_disabled() will be false.

The under match is more serious. When kdb is used instead of kgdb to access
the debugger then kgdb_connected is not set in all the places that the
debug core updates sw breakpoints (and hence flushes the icache). This
can lead to deadlock.

Fix by replacing the ad-hoc check with the proper kgdb macro. This also
allows us to drop the #ifdef wrapper.

Fixes: 3b8c9f1cdfc5 ("arm64: IPI each CPU after invalidating the I-cache for kernel mappings")
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200504170518.2959478-1-daniel.thompson@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:29:17 +08:00
Gavin Shan 2eb1ad02ab arm64/kernel: Fix range on invalidating dcache for boot page tables
[ Upstream commit 9d2d75ede59bc1edd8561f2ee9d4702a5ea0ae30 ]

Prior to commit 8eb7e28d4c642c31 ("arm64/mm: move runtime pgds to
rodata"), idmap_pgd_dir, tramp_pg_dir, reserved_ttbr0, swapper_pg_dir,
and init_pg_dir were contiguous at the end of the kernel image. The
maintenance at the end of __create_page_tables assumed these were
contiguous, and affected everything from the start of idmap_pg_dir
to the end of init_pg_dir.

That commit moved all but init_pg_dir into the .rodata section, with
other data placed between idmap_pg_dir and init_pg_dir, but did not
update the maintenance. Hence the maintenance is performed on much
more data than necessary (but as the bootloader previously made this
clean to the PoC there is no functional problem).

As we only alter idmap_pg_dir, and init_pg_dir, we only need to perform
maintenance for these. As the other dirs are in .rodata, the bootloader
will have initialised them as expected and cleaned them to the PoC. The
kernel will initialize them as necessary after enabling the MMU.

This patch reworks the maintenance to only cover the idmap_pg_dir and
init_pg_dir to avoid this unnecessary work.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200427235700.112220-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:29:16 +08:00
Marc Zyngier 30276ba31c KVM: arm64: Save the host's PtrAuth keys in non-preemptible context
commit ef3e40a7ea8dbe2abd0a345032cd7d5023b9684f upstream.

When using the PtrAuth feature in a guest, we need to save the host's
keys before allowing the guest to program them. For that, we dump
them in a per-CPU data structure (the so called host context).

But both call sites that do this are in preemptible context,
which may end up in disaster should the vcpu thread get preempted
before reentering the guest.

Instead, save the keys eagerly on each vcpu_load(). This has an
increased overhead, but is at least safe.

Cc: stable@vger.kernel.org
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:14 +08:00
Marc Zyngier 5da00758ac KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception
commit 0370964dd3ff7d3d406f292cb443a927952cbd05 upstream.

On a VHE system, the EL1 state is left in the CPU most of the time,
and only syncronized back to memory when vcpu_put() is called (most
of the time on preemption).

Which means that when injecting an exception, we'd better have a way
to either:
(1) write directly to the EL1 sysregs
(2) synchronize the state back to memory, and do the changes there

For an AArch64, we already do (1), so we are safe. Unfortunately,
doing the same thing for AArch32 would be pretty invasive. Instead,
we can easily implement (2) by calling the put/load architectural
backends, and keep preemption disabled. We can then reload the
state back into EL1.

Cc: stable@vger.kernel.org
Reported-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:14 +08:00
Marc Zyngier d8b09097bf KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts
commit 3204be4109ad681523e3461ce64454c79278450a upstream.

AArch32 CP1x registers are overlayed on their AArch64 counterparts
in the vcpu struct. This leads to an interesting problem as they
are stored in their CPU-local format, and thus a CP1x register
doesn't "hit" the lower 32bit portion of the AArch64 register on
a BE host.

To workaround this unfortunate situation, introduce a bias trick
in the vcpu_cp1x() accessors which picks the correct half of the
64bit register.

Cc: stable@vger.kernel.org
Reported-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:10 +08:00