Commit Graph

1073 Commits

Author SHA1 Message Date
Andrey Konovalov
f05842cfb9 kasan, arm64: allow using KUnit tests with HW_TAGS mode
On a high level, this patch allows running KUnit KASAN tests with the
hardware tag-based KASAN mode.

Internally, this change reenables tag checking at the end of each KASAN
test that triggers a tag fault and leads to tag checking being disabled.

Also simplify is_write calculation in report_tag_fault.

With this patch KASAN tests are still failing for the hardware tag-based
mode; fixes come in the next few patches.

[andreyknvl@google.com: export HW_TAGS symbols for KUnit tests]
  Link: https://lkml.kernel.org/r/e7eeb252da408b08f0c81b950a55fb852f92000b.1613155970.git.andreyknvl@google.com

Link: https://linux-review.googlesource.com/id/Id94dc9eccd33b23cda4950be408c27f879e474c8
Link: https://lkml.kernel.org/r/51b23112cf3fd62b8f8e9df81026fa2b15870501.1610733117.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:31 -08:00
Linus Torvalds
99ca0edb41 arm64 updates for 5.12
- vDSO build improvements including support for building with BSD.
 
  - Cleanup to the AMU support code and initialisation rework to support
    cpufreq drivers built as modules.
 
  - Removal of synthetic frame record from exception stack when entering
    the kernel from EL0.
 
  - Add support for the TRNG firmware call introduced by Arm spec
    DEN0098.
 
  - Cleanup and refactoring across the board.
 
  - Avoid calling arch_get_random_seed_long() from
    add_interrupt_randomness()
 
  - Perf and PMU updates including support for Cortex-A78 and the v8.3
    SPE extensions.
 
  - Significant steps along the road to leaving the MMU enabled during
    kexec relocation.
 
  - Faultaround changes to initialise prefaulted PTEs as 'old' when
    hardware access-flag updates are supported, which drastically
    improves vmscan performance.
 
  - CPU errata updates for Cortex-A76 (#1463225) and Cortex-A55
    (#1024718)
 
  - Preparatory work for yielding the vector unit at a finer granularity
    in the crypto code, which in turn will one day allow us to defer
    softirq processing when it is in use.
 
  - Support for overriding CPU ID register fields on the command-line.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:

 - vDSO build improvements including support for building with BSD.

 - Cleanup to the AMU support code and initialisation rework to support
   cpufreq drivers built as modules.

 - Removal of synthetic frame record from exception stack when entering
   the kernel from EL0.

 - Add support for the TRNG firmware call introduced by Arm spec
   DEN0098.

 - Cleanup and refactoring across the board.

 - Avoid calling arch_get_random_seed_long() from
   add_interrupt_randomness()

 - Perf and PMU updates including support for Cortex-A78 and the v8.3
   SPE extensions.

 - Significant steps along the road to leaving the MMU enabled during
   kexec relocation.

 - Faultaround changes to initialise prefaulted PTEs as 'old' when
   hardware access-flag updates are supported, which drastically
   improves vmscan performance.

 - CPU errata updates for Cortex-A76 (#1463225) and Cortex-A55
   (#1024718)

 - Preparatory work for yielding the vector unit at a finer granularity
   in the crypto code, which in turn will one day allow us to defer
   softirq processing when it is in use.

 - Support for overriding CPU ID register fields on the command-line.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits)
  drivers/perf: Replace spin_lock_irqsave to spin_lock
  mm: filemap: Fix microblaze build failure with 'mmu_defconfig'
  arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+
  arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line
  arm64: Defer enabling pointer authentication on boot core
  arm64: cpufeatures: Allow disabling of BTI from the command-line
  arm64: Move "nokaslr" over to the early cpufeature infrastructure
  KVM: arm64: Document HVC_VHE_RESTART stub hypercall
  arm64: Make kvm-arm.mode={nvhe, protected} an alias of id_aa64mmfr1.vh=0
  arm64: Add an aliasing facility for the idreg override
  arm64: Honor VHE being disabled from the command-line
  arm64: Allow ID_AA64MMFR1_EL1.VH to be overridden from the command line
  arm64: cpufeature: Add an early command-line cpufeature override facility
  arm64: Extract early FDT mapping from kaslr_early_init()
  arm64: cpufeature: Use IDreg override in __read_sysreg_by_encoding()
  arm64: cpufeature: Add global feature override facility
  arm64: Move SCTLR_EL1 initialisation to EL-agnostic code
  arm64: Simplify init_el2_state to be non-VHE only
  arm64: Move VHE-specific SPE setup to mutate_to_vhe()
  arm64: Drop early setting of MDSCR_EL2.TPMS
  ...
2021-02-21 13:08:42 -08:00
Will Deacon
1d32854ea7 Merge branch 'for-next/misc' into for-next/core
Miscellaneous arm64 changes for 5.12.

* for-next/misc:
  arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+
  arm64: vmlinux.ld.S: add assertion for tramp_pg_dir offset
  arm64: vmlinux.ld.S: add assertion for reserved_pg_dir offset
  arm64/ptdump:display the Linear Mapping start marker
  arm64: ptrace: Fix missing return in hw breakpoint code
  KVM: arm64: Move __hyp_set_vectors out of .hyp.text
  arm64: Include linux/io.h in mm/mmap.c
  arm64: cacheflush: Remove stale comment
  arm64: mm: Remove unused header file
  arm64/sparsemem: reduce SECTION_SIZE_BITS
  arm64/mm: Add warning for outside range requests in vmemmap_populate()
  arm64: Drop workaround for broken 'S' constraint with GCC 4.9
2021-02-12 15:07:34 +00:00
Will Deacon
b374d0f981 Merge branch 'for-next/kexec' into for-next/core
Significant steps along the road to leaving the MMU enabled during kexec
relocation.

* for-next/kexec:
  arm64: hibernate: add __force attribute to gfp_t casting
  arm64: kexec: arm64_relocate_new_kernel don't use x0 as temp
  arm64: kexec: arm64_relocate_new_kernel clean-ups and optimizations
  arm64: kexec: call kexec_image_info only once
  arm64: kexec: move relocation function setup
  arm64: trans_pgd: hibernate: idmap the single page that holds the copy page routines
  arm64: mm: Always update TCR_EL1 from __cpu_set_tcr_t0sz()
  arm64: trans_pgd: pass NULL instead of init_mm to *_populate functions
  arm64: trans_pgd: pass allocator trans_pgd_create_copy
  arm64: trans_pgd: make trans_pgd_map_page generic
  arm64: hibernate: move page handling function to new trans_pgd.c
  arm64: hibernate: variable pudp is used instead of pd4dp
  arm64: kexec: make dtb_mem always enabled
2021-02-12 15:03:53 +00:00
Will Deacon
90eb8c9d94 Merge branch 'for-next/errata' into for-next/core
Rework of the workaround for Cortex-A76 erratum 1463225 to fit in better
with the ongoing exception entry cleanups and changes to the detection
code for Cortex-A55 erratum 1024718 since it applies to all revisions of
the silicon.

* for-next/errata:
  arm64: entry: consolidate Cortex-A76 erratum 1463225 workaround
  arm64: Extend workaround for erratum 1024718 to all versions of Cortex-A55
2021-02-12 14:57:13 +00:00
Will Deacon
88ddf0df16 Merge branch 'for-next/cpufeature' into for-next/core
Support for overriding CPU ID register fields on the command-line, which
allows us to disable certain features which the kernel would otherwise
use unconditionally when detected.

* for-next/cpufeature: (22 commits)
  arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line
  arm64: Defer enabling pointer authentication on boot core
  arm64: cpufeatures: Allow disabling of BTI from the command-line
  arm64: Move "nokaslr" over to the early cpufeature infrastructure
  KVM: arm64: Document HVC_VHE_RESTART stub hypercall
  arm64: Make kvm-arm.mode={nvhe, protected} an alias of id_aa64mmfr1.vh=0
  arm64: Add an aliasing facility for the idreg override
  arm64: Honor VHE being disabled from the command-line
  arm64: Allow ID_AA64MMFR1_EL1.VH to be overridden from the command line
  arm64: cpufeature: Add an early command-line cpufeature override facility
  arm64: Extract early FDT mapping from kaslr_early_init()
  arm64: cpufeature: Use IDreg override in __read_sysreg_by_encoding()
  arm64: cpufeature: Add global feature override facility
  arm64: Move SCTLR_EL1 initialisation to EL-agnostic code
  arm64: Simplify init_el2_state to be non-VHE only
  arm64: Move VHE-specific SPE setup to mutate_to_vhe()
  arm64: Drop early setting of MDSCR_EL2.TPMS
  arm64: Initialise as nVHE before switching to VHE
  arm64: Provide an 'upgrade to VHE' stub hypercall
  arm64: Turn the MMU-on sequence into a macro
  ...
2021-02-12 14:53:19 +00:00
Marc Zyngier
93ad55b785 arm64: cpufeatures: Allow disabling of BTI from the command-line
In order to be able to disable BTI at runtime, whether it is
for testing purposes, or to work around HW issues, let's add
support for overriding the ID_AA64PFR1_EL1.BTI field.

This is further mapped on the arm64.nobti command-line alias.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Brazdil <dbrazdil@google.com>
Tested-by: Srinivas Ramana <sramana@codeaurora.org>
Link: https://lore.kernel.org/r/20210208095732.3267263-21-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-09 13:50:57 +00:00
Mark Rutland
6459b84697 arm64: entry: consolidate Cortex-A76 erratum 1463225 workaround
The workaround for Cortex-A76 erratum 1463225 is split across the
syscall and debug handlers in separate files. This structure currently
forces us to do some redundant work for debug exceptions from EL0, is a
little difficult to follow, and gets in the way of some future rework of
the exception entry code as it requires exceptions to be unmasked late
in the syscall handling path.

To simplify things, and as a preparatory step for future rework of
exception entry, this patch moves all the workaround logic into
entry-common.c. As the debug handler only needs to run for EL1 debug
exceptions, we no longer call it for EL0 debug exceptions, and no longer
need to check user_mode(regs) as this is always false. For clarity
cortex_a76_erratum_1463225_debug_handler() is changed to return bool.

In the SVC path, the workaround is applied earlier, but this should have
no functional impact as exceptions are still masked. In the debug path
we run the fixup before explicitly disabling preemption, but we will not
attempt to preempt before returning from the exception.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210202120341.28858-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-08 17:39:02 +00:00
Marc Zyngier
8cc8a32415 arm64: Turn the MMU-on sequence into a macro
Turning the MMU on is a popular sport in the arm64 kernel, and
we do it more than once, or even twice. As we are about to add
even more, let's turn it into a macro.

No expected functional change.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Brazdil <dbrazdil@google.com>
Link: https://lore.kernel.org/r/20210208095732.3267263-4-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-08 12:51:26 +00:00
Marc Zyngier
b161f92482 arm64: Fix outdated TCR setup comment
The arm64 kernel has long be able to use more than 39bit VAs.
Since day one, actually. Let's rewrite the offending comment.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Brazdil <dbrazdil@google.com>
Link: https://lore.kernel.org/r/20210208095732.3267263-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-08 12:51:26 +00:00
Miaohe Lin
abd4737f67 mm/arm64: Correct obsolete comment in do_page_fault()
commit d8ed45c5dc ("mmap locking API: use coccinelle to convert mmap_sem
rwsem call sites") has convertd down_read_trylock() to mmap_read_trylock().
But it forgot to update the relevant comment.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Link: https://lore.kernel.org/r/20210205090919.63382-1-linmiaohe@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-05 18:43:47 +00:00
Hailong Liu
b9ba680969 arm64/ptdump:display the Linear Mapping start marker
The current /sys/kernel/debug/kernel_page_tables does not display the
*Linear Mapping start* marker on arm64, which I think should be paired
with the *Linear Mapping end* marker.

Since *Linear Mapping start* is the first marker, use initialise 'level'
to -1 in order to display it.

Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Link: https://lore.kernel.org/r/20210202150749.10104-1-liuhailongg6@163.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-02 21:12:35 +00:00
Catalin Marinas
91cb2c8b07 arm64: Do not pass tagged addresses to __is_lm_address()
Commit 519ea6f1c8 ("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: 519ea6f1c8 ("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
2021-02-02 17:44:47 +00:00
James Morse
7018d467ff arm64: trans_pgd: hibernate: idmap the single page that holds the copy page routines
To resume from hibernate, the contents of memory are restored from
the swap image. This may overwrite any page, including the running
kernel and its page tables.

Hibernate copies the code it uses to do the restore into a single
page that it knows won't be overwritten, and maps it with page tables
built from pages that won't be overwritten.

Today the address it uses for this mapping is arbitrary, but to allow
kexec to reuse this code, it needs to be idmapped. To idmap the page
we must avoid the kernel helpers that have VA_BITS baked in.

Convert create_single_mapping() to take a single PA, and idmap it.
The page tables are built in the reverse order to normal using
pfn_pte() to stir in any bits between 52:48. T0SZ is always increased
to cover 48bits, or 52 if the copy code has bits 52:48 in its PA.

Signed-off-by: James Morse <james.morse@arm.com>

[Adopted the original patch from James to trans_pgd interface, so it can be
commonly used by both Kexec and Hibernate. Some minor clean-ups.]

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/linux-arm-kernel/20200115143322.214247-4-james.morse@arm.com/
Link: https://lore.kernel.org/r/20210125191923.1060122-9-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 15:41:12 +00:00
Pavel Tatashin
5de59884ac arm64: trans_pgd: pass NULL instead of init_mm to *_populate functions
trans_pgd_* should be independent from mm context because the tables that
are created by this code are used when there are no mm context around, as
it is between kernels. Simply replace mm_init's with NULL.

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-7-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 15:41:12 +00:00
Pavel Tatashin
89d1410f4a arm64: trans_pgd: pass allocator trans_pgd_create_copy
Make trans_pgd_create_copy and its subroutines to use allocator that is
passed as an argument

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-6-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 15:41:12 +00:00
Pavel Tatashin
50f53fb721 arm64: trans_pgd: make trans_pgd_map_page generic
kexec is going to use a different allocator, so make
trans_pgd_map_page to accept allocator as an argument, and also
kexec is going to use a different map protection, so also pass
it via argument.

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-5-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 15:41:12 +00:00
Pavel Tatashin
072e3d96a7 arm64: hibernate: move page handling function to new trans_pgd.c
Now, that we abstracted the required functions move them to a new home.
Later, we will generalize these function in order to be useful outside
of hibernation.

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20210125191923.1060122-4-pasha.tatashin@soleen.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 15:41:11 +00:00
Will Deacon
c7b9095e87 arm64: Include linux/io.h in mm/mmap.c
Commit 507d664450 ("arm64: mm: Remove unused header file") removed
a bunch of apparently "unused" header inclusions from our mm/mmap.c
implementation, but in doing so introduced the following warning when
building with W=1:

>> arch/arm64/mm/mmap.c:17:5: warning: no previous prototype for 'valid_phys_addr_range' [-Wmissing-prototypes]
      17 | int valid_phys_addr_range(phys_addr_t addr, size_t size)
         |     ^~~~~~~~~~~~~~~~~~~~~
>> arch/arm64/mm/mmap.c:36:5: warning: no previous prototype for 'valid_mmap_phys_addr_range' [-Wmissing-prototypes]
      36 | int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~~

Add back the linux/io.h header inclusion to pull in the missing
prototypes.

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/202101271438.V9TmBC31-lkp@intel.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-27 12:52:16 +00:00
Shaokun Zhang
507d664450 arm64: mm: Remove unused header file
Many header files are never used, let's remove them directly.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1611663884-43329-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-26 23:23:19 +00:00
Anshuman Khandual
edb739eed8 arm64/mm: Add warning for outside range requests in vmemmap_populate()
vmemmap_populate() does not validate the requested vmemmap address range to
be inside the platform assigned space i.e [VMEMMAP_START..VMEMMAP_END] for
vmemmap. Instead it would just go ahead and create the mapping which might
then overlap with other sections in the kernel virtual address space.

Just adding an warning here for range overrun which would help detect the
problem earlier on, before a potential struct page corruption. This also
makes vmemmap_populate() symmetrical with vmemmap_free() which already has
a similar warning.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1609845851-25064-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 12:27:57 +00:00
Andrey Konovalov
3ed86b9a71 kasan, arm64: fix pointer tags in KASAN reports
As of the "arm64: expose FAR_EL1 tag bits in siginfo" patch, the address
that is passed to report_tag_fault has pointer tags in the format of 0x0X,
while KASAN uses 0xFX format (note the difference in the top 4 bits).

Fix up the pointer tag for kernel pointers in do_tag_check_fault by
setting them to the same value as bit 55. Explicitly use __untagged_addr()
instead of untagged_addr(), as the latter doesn't affect TTBR1 addresses.

Fixes: dceec3ff78 ("arm64: expose FAR_EL1 tag bits in siginfo")
Fixes: 4291e9ee61 ("kasan, arm64: print report from tag fault handler")
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://linux-review.googlesource.com/id/I9ced973866036d8679e8f4ae325de547eb969649
Link: https://lore.kernel.org/r/ff30b0afe6005fd046f9ac72bfb71822aedccd89.1610731872.git.andreyknvl@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-01-18 18:15:49 +00:00
Catalin Marinas
d78050ee35 arm64: Remove arm64_dma32_phys_limit and its uses
With the introduction of a dynamic ZONE_DMA range based on DT or IORT
information, there's no need for CMA allocations from the wider
ZONE_DMA32 since on most platforms ZONE_DMA will cover the 32-bit
addressable range. Remove the arm64_dma32_phys_limit and set
arm64_dma_phys_limit to cover the smallest DMA range required on the
platform. CMA allocation and crashkernel reservation now go in the
dynamically sized ZONE_DMA, allowing correct functionality on RPi4.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Zhou <chenzhou10@huawei.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> # On RPi4B
2021-01-12 17:49:25 +00:00
Catalin Marinas
f34d93f30d arm64: kasan: Set TCR_EL1.TBID1 when KASAN_HW_TAGS is enabled
Commit 49b3cf035e ("kasan: arm64: set TCR_EL1.TBID1 when enabled") set
the TBID1 bit for the KASAN_SW_TAGS configuration, freeing up 8 bits to
be used by PAC. With in-kernel MTE now in mainline, also set this bit
for the KASAN_HW_TAGS configuration.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
2021-01-05 17:52:19 +00:00
Nicolas Saenz Julienne
095507dc13 arm64: mm: Fix ARCH_LOW_ADDRESS_LIMIT when !CONFIG_ZONE_DMA
Systems configured with CONFIG_ZONE_DMA32, CONFIG_ZONE_NORMAL and
!CONFIG_ZONE_DMA will fail to properly setup ARCH_LOW_ADDRESS_LIMIT. The
limit will default to ~0ULL, effectively spanning the whole memory,
which is too high for a configuration that expects low memory to be
capped at 4GB.

Fix ARCH_LOW_ADDRESS_LIMIT by falling back to arm64_dma32_phys_limit
when arm64_dma_phys_limit isn't set. arm64_dma32_phys_limit will honour
CONFIG_ZONE_DMA32, or span the entire memory when not enabled.

Fixes: 1a8e1cef76 ("arm64: use both ZONE_DMA and ZONE_DMA32")
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20201218163307.10150-1-nsaenzjulienne@suse.de
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-01-04 11:06:13 +00:00
Andrey Konovalov
4291e9ee61 kasan, arm64: print report from tag fault handler
Add error reporting for hardware tag-based KASAN.  When
CONFIG_KASAN_HW_TAGS is enabled, print KASAN report from the arm64 tag
fault handler.

SAS bits aren't set in ESR for all faults reported in EL1, so it's
impossible to find out the size of the access the caused the fault.  Adapt
KASAN reporting code to handle this case.

Link: https://lkml.kernel.org/r/b559c82b6a969afedf53b4694b475f0234067a1a.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Co-developed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00
Andrey Konovalov
0fea6e9af8 kasan, arm64: expand CONFIG_KASAN checks
Some #ifdef CONFIG_KASAN checks are only relevant for software KASAN modes
(either related to shadow memory or compiler instrumentation).  Expand
those into CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS.

Link: https://lkml.kernel.org/r/e6971e432dbd72bb897ff14134ebb7e169bdcf0c.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00
Vincenzo Frascino
bfc62c5985 arm64: kasan: allow enabling in-kernel MTE
Hardware tag-based KASAN relies on Memory Tagging Extension (MTE) feature
and requires it to be enabled.  MTE supports

This patch adds a new mte_enable_kernel() helper, that enables MTE in
Synchronous mode in EL1 and is intended to be called from KASAN runtime
during initialization.

The Tag Checking operation causes a synchronous data abort as a
consequence of a tag check fault when MTE is configured in synchronous
mode.

As part of this change enable match-all tag for EL1 to allow the kernel to
access user pages without faulting.  This is required because the kernel
does not have knowledge of the tags set by the user in a page.

Note: For MTE, the TCF bit field in SCTLR_EL1 affects only EL1 in a
similar way as TCF0 affects EL0.

MTE that is built on top of the Top Byte Ignore (TBI) feature hence we
enable it as part of this patch as well.

Link: https://lkml.kernel.org/r/7352b0a0899af65c2785416c8ca6bf3845b66fa1.1606161801.git.andreyknvl@google.com
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Co-developed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Vincenzo Frascino
98c970da8b arm64: mte: add in-kernel tag fault handler
Add the implementation of the in-kernel fault handler.

When a tag fault happens on a kernel address:
* MTE is disabled on the current CPU,
* the execution continues.

When a tag fault happens on a user address:
* the kernel executes do_bad_area() and panics.

The tag fault handler for kernel addresses is currently empty and will be
filled in by a future commit.

  Link: https://lkml.kernel.org/r/20201203102628.GB2224@gaia

Link: https://lkml.kernel.org/r/ad31529b073e22840b7a2246172c2b67747ed7c4.1606161801.git.andreyknvl@google.com
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Co-developed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: ensure CONFIG_ARM64_PAN is enabled with MTE]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Vincenzo Frascino
e5b8d92189 arm64: mte: reset the page tag in page->flags
The hardware tag-based KASAN for compatibility with the other modes stores
the tag associated to a page in page->flags.  Due to this the kernel
faults on access when it allocates a page with an initial tag and the user
changes the tags.

Reset the tag associated by the kernel to a page in all the meaningful
places to prevent kernel faults on access.

Note: An alternative to this approach could be to modify page_to_virt().
This though could end up being racy, in fact if a CPU checks the
PG_mte_tagged bit and decides that the page is not tagged but another CPU
maps the same with PROT_MTE and becomes tagged the subsequent kernel
access would fail.

Link: https://lkml.kernel.org/r/9073d4e973747a6f78d5bdd7ebe17f290d087096.1606161801.git.andreyknvl@google.com
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Andrey Konovalov
60a3a5fe95 kasan, arm64: rename kasan_init_tags and mark as __init
Rename kasan_init_tags() to kasan_init_sw_tags() as the upcoming hardware
tag-based KASAN mode will have its own initialization routine.  Also
similarly to kasan_init() mark kasan_init_tags() as __init.

Link: https://lkml.kernel.org/r/71e52af72a09f4b50c8042f16101c60e50649fbb.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Andrey Konovalov
28ab35841c kasan, arm64: move initialization message
Software tag-based KASAN mode is fully initialized with kasan_init_tags(),
while the generic mode only requires kasan_init().  Move the
initialization message for tag-based mode into kasan_init_tags().

Also fix pr_fmt() usage for KASAN code: generic.c doesn't need it as it
doesn't use any printing functions; tag-based mode should use "kasan:"
instead of KBUILD_MODNAME (which stands for file name).

Link: https://lkml.kernel.org/r/29a30ea4e1750450dd1f693d25b7b6cb05913ecf.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Andrey Konovalov
d73b49365e kasan, arm64: only use kasan_depth for software modes
This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.

Hardware tag-based KASAN won't use kasan_depth.  Only define and use it
when one of the software KASAN modes are enabled.

No functional changes for software modes.

Link: https://lkml.kernel.org/r/e16f15aeda90bc7fb4dfc2e243a14b74cc5c8219.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Andrey Konovalov
afe6ef80dc kasan, arm64: only init shadow for software modes
This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.

Hardware tag-based KASAN won't be using shadow memory.  Only initialize it
when one of the software KASAN modes are enabled.

No functional changes for software modes.

Link: https://lkml.kernel.org/r/d1742eea2cd728d150d49b144e49b6433405c7ba.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:07 -08:00
Linus Torvalds
5ba836eb9f arm64 fixes/updates:
- Work around broken GCC 4.9 handling of "S" asm constraint.
 
 - Suppress W=1 missing prototype warnings.
 
 - Warn the user when a small VA_BITS value cannot map the available
   memory.
 
 - Drop the useless update to per-cpu cycles.
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull more arm64 updates from Catalin Marinas:
 "These are some some trivial updates that mostly fix/clean-up code
  pushed during the merging window:

   - Work around broken GCC 4.9 handling of "S" asm constraint

   - Suppress W=1 missing prototype warnings

   - Warn the user when a small VA_BITS value cannot map the available
     memory

   - Drop the useless update to per-cpu cycles"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Work around broken GCC 4.9 handling of "S" constraint
  arm64: Warn the user when a small VA_BITS value wastes memory
  arm64: entry: suppress W=1 prototype warnings
  arm64: topology: Drop the useless update to per-cpu cycles
2020-12-18 10:57:27 -08:00
Linus Torvalds
e2ae634014 RISC-V Patches for the 5.11 Merge Window, Part 1
We have a handful of new kernel features for 5.11:
 
 * Support for the contiguous memory allocator.
 * Support for IRQ Time Accounting
 * Support for stack tracing
 * Support for strict /dev/mem
 * Support for kernel section protection
 
 I'm being a bit conservative on the cutoff for this round due to the
 timing, so this is all the new development I'm going to take for this
 cycle (even if some of it probably normally would have been OK).  There
 are, however, some fixes on the list that I will likely be sending along
 either later this week or early next week.
 
 There is one issue in here: one of my test configurations
 (PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of the
 .text.init alignment patch.  With any luck we'll sort out the issue, but
 given how many bugs get fixed all over the place and how unrelated those
 features seem my guess is that we're just running into something that's
 been lurking for a while and has already been fixed in the newer QEMU
 (though I wouldn't be surprised if it's one of these implicit
 assumptions we have in the boot flow).  If it was hardware I'd be
 strongly inclined to look more closely, but given that users can upgrade
 their simulators I'm less worried about it.
 
 There are two merge conflicts, both in build files.  They're both a bit
 clunky: arch/riscv/Kconfig is out of order (I have a script that's
 supposed to keep them in order, I'll fix it) and lib/Makefile is out of
 order (though GENERIC_LIB here doesn't mean quite what it does above).
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Merge tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:
 "We have a handful of new kernel features for 5.11:

   - Support for the contiguous memory allocator.

   - Support for IRQ Time Accounting

   - Support for stack tracing

   - Support for strict /dev/mem

   - Support for kernel section protection

  I'm being a bit conservative on the cutoff for this round due to the
  timing, so this is all the new development I'm going to take for this
  cycle (even if some of it probably normally would have been OK). There
  are, however, some fixes on the list that I will likely be sending
  along either later this week or early next week.

  There is one issue in here: one of my test configurations
  (PREEMPT{,_DEBUG}=y) fails to boot on QEMU 5.0.0 (from April) as of
  the .text.init alignment patch.

  With any luck we'll sort out the issue, but given how many bugs get
  fixed all over the place and how unrelated those features seem my
  guess is that we're just running into something that's been lurking
  for a while and has already been fixed in the newer QEMU (though I
  wouldn't be surprised if it's one of these implicit assumptions we
  have in the boot flow). If it was hardware I'd be strongly inclined to
  look more closely, but given that users can upgrade their simulators
  I'm less worried about it"

* tag 'riscv-for-linus-5.11-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  arm64: Use the generic devmem_is_allowed()
  arm: Use the generic devmem_is_allowed()
  RISC-V: Use the new generic devmem_is_allowed()
  lib: Add a generic version of devmem_is_allowed()
  riscv: Fixed kernel test robot warning
  riscv: kernel: Drop unused clean rule
  riscv: provide memmove implementation
  RISC-V: Move dynamic relocation section under __init
  RISC-V: Protect all kernel sections including init early
  RISC-V: Align the .init.text section
  RISC-V: Initialize SBI early
  riscv: Enable ARCH_STACKWALK
  riscv: Make stack walk callback consistent with generic code
  riscv: Cleanup stacktrace
  riscv: Add HAVE_IRQ_TIME_ACCOUNTING
  riscv: Enable CMA support
  riscv: Ignore Image.* and loader.bin
  riscv: Clean up boot dir
  riscv: Fix compressed Image formats build
  RISC-V: Add kernel image sections to the resource tree
2020-12-18 10:43:07 -08:00
Linus Torvalds
ac73e3dc8a Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...
2020-12-15 12:53:37 -08:00
Mike Rapoport
32a0de886e arch, mm: make kernel_page_present() always available
For architectures that enable ARCH_HAS_SET_MEMORY having the ability to
verify that a page is mapped in the kernel direct map can be useful
regardless of hibernation.

Add RISC-V implementation of kernel_page_present(), update its forward
declarations and stubs to be a part of set_memory API and remove ugly
ifdefery in inlcude/linux/mm.h around current declarations of
kernel_page_present().

Link: https://lkml.kernel.org/r/20201109192128.960-5-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:43 -08:00
Mike Rapoport
5d6ad668f3 arch, mm: restore dependency of __kernel_map_pages() on DEBUG_PAGEALLOC
The design of DEBUG_PAGEALLOC presumes that __kernel_map_pages() must
never fail.  With this assumption is wouldn't be safe to allow general
usage of this function.

Moreover, some architectures that implement __kernel_map_pages() have this
function guarded by #ifdef DEBUG_PAGEALLOC and some refuse to map/unmap
pages when page allocation debugging is disabled at runtime.

As all the users of __kernel_map_pages() were converted to use
debug_pagealloc_map_pages() it is safe to make it available only when
DEBUG_PAGEALLOC is set.

Link: https://lkml.kernel.org/r/20201109192128.960-4-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:43 -08:00
Mike Rapoport
4f5b0c1789 arm, arm64: move free_unused_memmap() to generic mm
ARM and ARM64 free unused parts of the memory map just before the
initialization of the page allocator. To allow holes in the memory map both
architectures overload pfn_valid() and define HAVE_ARCH_PFN_VALID.

Allowing holes in the memory map for FLATMEM may be useful for small
machines, such as ARC and m68k and will enable those architectures to cease
using DISCONTIGMEM and still support more than one memory bank.

Move the functions that free unused memory map to generic mm and enable
them in case HAVE_ARCH_PFN_VALID=y.

Link: https://lkml.kernel.org/r/20201101170454.9567-10-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>	[arm64]
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:42 -08:00
Marc Zyngier
31f80a4e96 arm64: Warn the user when a small VA_BITS value wastes memory
The memblock code ignores any memory that doesn't fit in the
linear mapping. In order to preserve the distance between two physical
memory locations and their mappings in the linear map, any hole between
two memory regions occupies the same space in the linear map.

On most systems, this is hardly a problem (the memory banks are close
together, and VA_BITS represents a large space compared to the available
memory *and* the potential gaps).

On NUMA systems, things are quite different: the gaps between the
memory nodes can be pretty large compared to the memory size itself,
and the range from memblock_start_of_DRAM() to memblock_end_of_DRAM()
can exceed the space described by VA_BITS.

Unfortunately, we're not very good at making this obvious to the user,
and on a D05 system (two sockets and 4 nodes with 64GB each)
accidentally configured with 39bit VA, we display something like this:

[    0.000000] NUMA: NODE_DATA [mem 0x1ffbffe100-0x1ffbffffff]
[    0.000000] NUMA: NODE_DATA [mem 0x2febfc1100-0x2febfc2fff]
[    0.000000] NUMA: Initmem setup node 2 [<memory-less node>]
[    0.000000] NUMA: NODE_DATA [mem 0x2febfbf200-0x2febfc10ff]
[    0.000000] NUMA: NODE_DATA(2) on node 1
[    0.000000] NUMA: Initmem setup node 3 [<memory-less node>]
[    0.000000] NUMA: NODE_DATA [mem 0x2febfbd300-0x2febfbf1ff]
[    0.000000] NUMA: NODE_DATA(3) on node 1

which isn't very explicit, and doesn't tell the user why 128GB
have suddently disappeared.

Let's add a warning message telling the user that memory has been
truncated, and offer a potential solution (bumping VA_BITS up).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20201215152918.1511108-1-maz@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-15 16:27:48 +00:00
Palmer Dabbelt
7d95a88f92
Add and use a generic version of devmem_is_allowed()
As part of adding STRICT_DEVMEM support to the RISC-V port, Zong provided an
implementation of devmem_is_allowed() that's exactly the same as the version in
a handful of other ports.  Rather than duplicate code, I've put a generic
version of this in lib/ and used it for the RISC-V port.

* palmer/generic-devmem:
  arm64: Use the generic devmem_is_allowed()
  arm: Use the generic devmem_is_allowed()
  RISC-V: Use the new generic devmem_is_allowed()
  lib: Add a generic version of devmem_is_allowed()
2020-12-11 12:30:26 -08:00
Palmer Dabbelt
6585bd8274
arm64: Use the generic devmem_is_allowed()
I recently copied this into lib/ for use by the RISC-V port.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-12-11 12:28:35 -08:00
Catalin Marinas
d889797530 Merge remote-tracking branch 'arm64/for-next/fixes' into for-next/core
* arm64/for-next/fixes: (26 commits)
  arm64: mte: fix prctl(PR_GET_TAGGED_ADDR_CTRL) if TCF0=NONE
  arm64: mte: Fix typo in macro definition
  arm64: entry: fix EL1 debug transitions
  arm64: entry: fix NMI {user, kernel}->kernel transitions
  arm64: entry: fix non-NMI kernel<->kernel transitions
  arm64: ptrace: prepare for EL1 irq/rcu tracking
  arm64: entry: fix non-NMI user<->kernel transitions
  arm64: entry: move el1 irq/nmi logic to C
  arm64: entry: prepare ret_to_user for function call
  arm64: entry: move enter_from_user_mode to entry-common.c
  arm64: entry: mark entry code as noinstr
  arm64: mark idle code as noinstr
  arm64: syscall: exit userspace before unmasking exceptions
  arm64: pgtable: Ensure dirty bit is preserved across pte_wrprotect()
  arm64: pgtable: Fix pte_accessible()
  ACPI/IORT: Fix doc warnings in iort.c
  arm64/fpsimd: add <asm/insn.h> to <asm/kprobes.h> to fix fpsimd build
  arm64: cpu_errata: Apply Erratum 845719 to KRYO2XX Silver
  arm64: proton-pack: Add KRYO2XX silver CPUs to spectre-v2 safe-list
  arm64: kpti: Add KRYO2XX gold/silver CPU cores to kpti safelist
  ...

# Conflicts:
#	arch/arm64/include/asm/exception.h
#	arch/arm64/kernel/sdei.c
2020-12-09 18:04:55 +00:00
Catalin Marinas
ba4259a6f8 Merge branch 'for-next/misc' into for-next/core
* for-next/misc:
  : Miscellaneous patches
  arm64: vmlinux.lds.S: Drop redundant *.init.rodata.*
  kasan: arm64: set TCR_EL1.TBID1 when enabled
  arm64: mte: optimize asynchronous tag check fault flag check
  arm64/mm: add fallback option to allocate virtually contiguous memory
  arm64/smp: Drop the macro S(x,s)
  arm64: consistently use reserved_pg_dir
  arm64: kprobes: Remove redundant kprobe_step_ctx

# Conflicts:
#	arch/arm64/kernel/vmlinux.lds.S
2020-12-09 18:04:48 +00:00
Catalin Marinas
e0f7a8d5e8 Merge branch 'for-next/uaccess' into for-next/core
* for-next/uaccess:
  : uaccess routines clean-up and set_fs() removal
  arm64: mark __system_matches_cap as __maybe_unused
  arm64: uaccess: remove vestigal UAO support
  arm64: uaccess: remove redundant PAN toggling
  arm64: uaccess: remove addr_limit_user_check()
  arm64: uaccess: remove set_fs()
  arm64: uaccess cleanup macro naming
  arm64: uaccess: split user/kernel routines
  arm64: uaccess: refactor __{get,put}_user
  arm64: uaccess: simplify __copy_user_flushcache()
  arm64: uaccess: rename privileged uaccess routines
  arm64: sdei: explicitly simulate PAN/UAO entry
  arm64: sdei: move uaccess logic to arch/arm64/
  arm64: head.S: always initialize PSTATE
  arm64: head.S: cleanup SCTLR_ELx initialization
  arm64: head.S: rename el2_setup -> init_kernel_el
  arm64: add C wrappers for SET_PSTATE_*()
  arm64: ensure ERET from kthread is illegal
2020-12-09 18:04:42 +00:00
Catalin Marinas
3c09ec59cd Merge branches 'for-next/kvm-build-fix', 'for-next/va-refactor', 'for-next/lto', 'for-next/mem-hotplug', 'for-next/cppc-ffh', 'for-next/pad-image-header', 'for-next/zone-dma-default-32-bit', 'for-next/signal-tag-bits' and 'for-next/cmdline-extended' into for-next/core
* for-next/kvm-build-fix:
  : Fix KVM build issues with 64K pages
  KVM: arm64: Fix build error in user_mem_abort()

* for-next/va-refactor:
  : VA layout changes
  arm64: mm: don't assume struct page is always 64 bytes
  Documentation/arm64: fix RST layout of memory.rst
  arm64: mm: tidy up top of kernel VA space
  arm64: mm: make vmemmap region a projection of the linear region
  arm64: mm: extend linear region for 52-bit VA configurations

* for-next/lto:
  : Upgrade READ_ONCE() to RCpc acquire on arm64 with LTO
  arm64: lto: Strengthen READ_ONCE() to acquire when CONFIG_LTO=y
  arm64: alternatives: Remove READ_ONCE() usage during patch operation
  arm64: cpufeatures: Add capability for LDAPR instruction
  arm64: alternatives: Split up alternative.h
  arm64: uaccess: move uao_* alternatives to asm-uaccess.h

* for-next/mem-hotplug:
  : Memory hotplug improvements
  arm64/mm/hotplug: Ensure early memory sections are all online
  arm64/mm/hotplug: Enable MEM_OFFLINE event handling
  arm64/mm/hotplug: Register boot memory hot remove notifier earlier
  arm64: mm: account for hotplug memory when randomizing the linear region

* for-next/cppc-ffh:
  : Add CPPC FFH support using arm64 AMU counters
  arm64: abort counter_read_on_cpu() when irqs_disabled()
  arm64: implement CPPC FFH support using AMUs
  arm64: split counter validation function
  arm64: wrap and generalise counter read functions

* for-next/pad-image-header:
  : Pad Image header to 64KB and unmap it
  arm64: head: tidy up the Image header definition
  arm64/head: avoid symbol names pointing into first 64 KB of kernel image
  arm64: omit [_text, _stext) from permanent kernel mapping

* for-next/zone-dma-default-32-bit:
  : Default to 32-bit wide ZONE_DMA (previously reduced to 1GB for RPi4)
  of: unittest: Fix build on architectures without CONFIG_OF_ADDRESS
  mm: Remove examples from enum zone_type comment
  arm64: mm: Set ZONE_DMA size based on early IORT scan
  arm64: mm: Set ZONE_DMA size based on devicetree's dma-ranges
  of: unittest: Add test for of_dma_get_max_cpu_address()
  of/address: Introduce of_dma_get_max_cpu_address()
  arm64: mm: Move zone_dma_bits initialization into zone_sizes_init()
  arm64: mm: Move reserve_crashkernel() into mem_init()
  arm64: Force NO_BLOCK_MAPPINGS if crashkernel reservation is required
  arm64: Ignore any DMA offsets in the max_zone_phys() calculation

* for-next/signal-tag-bits:
  : Expose the FAR_EL1 tag bits in siginfo
  arm64: expose FAR_EL1 tag bits in siginfo
  signal: define the SA_EXPOSE_TAGBITS bit in sa_flags
  signal: define the SA_UNSUPPORTED bit in sa_flags
  arch: provide better documentation for the arch-specific SA_* flags
  signal: clear non-uapi flag bits when passing/returning sa_flags
  arch: move SA_* definitions to generic headers
  parisc: start using signal-defs.h
  parisc: Drop parisc special case for __sighandler_t

* for-next/cmdline-extended:
  : Add support for CONFIG_CMDLINE_EXTENDED
  arm64: Extend the kernel command line from the bootloader
  arm64: kaslr: Refactor early init command line parsing
2020-12-09 18:04:35 +00:00
Mark Rutland
3d2403fd10 arm64: uaccess: remove set_fs()
Now that the uaccess primitives dont take addr_limit into account, we
have no need to manipulate this via set_fs() and get_fs(). Remove
support for these, along with some infrastructure this renders
redundant.

We no longer need to flip UAO to access kernel memory under KERNEL_DS,
and head.S unconditionally clears UAO for all kernel configurations via
an ERET in init_kernel_el. Thus, we don't need to dynamically flip UAO,
nor do we need to context-switch it. However, we still need to adjust
PAN during SDEI entry.

Masking of __user pointers no longer needs to use the dynamic value of
addr_limit, and can use a constant derived from the maximum possible
userspace task size. A new TASK_SIZE_MAX constant is introduced for
this, which is also used by core code. In configurations supporting
52-bit VAs, this may include a region of unusable VA space above a
48-bit TTBR0 limit, but never includes any portion of TTBR1.

Note that TASK_SIZE_MAX is an exclusive limit, while USER_DS and
KERNEL_DS were inclusive limits, and is converted to a mask by
subtracting one.

As the SDEI entry code repurposes the otherwise unnecessary
pt_regs::orig_addr_limit field to store the TTBR1 of the interrupted
context, for now we rename that to pt_regs::sdei_ttbr1. In future we can
consider factoring that out.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201202131558.39270-10-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-02 19:49:11 +00:00
Mark Rutland
2ffac9e3fd arm64: head.S: cleanup SCTLR_ELx initialization
Let's make SCTLR_ELx initialization a bit clearer by using meaningful
names for the initialization values, following the same scheme for
SCTLR_EL1 and SCTLR_EL2.

These definitions will be used more widely in subsequent patches.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201113124937.20574-5-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-02 19:44:03 +00:00
Mark Rutland
2a9b3e6ac6 arm64: entry: fix EL1 debug transitions
In debug_exception_enter() and debug_exception_exit() we trace hardirqs
on/off while RCU isn't guaranteed to be watching, and we don't save and
restore the hardirq state, and so may return with this having changed.

Handle this appropriately with new entry/exit helpers which do the bare
minimum to ensure this is appropriately maintained, without marking
debug exceptions as NMIs. These are placed in entry-common.c with the
other entry/exit helpers.

In future we'll want to reconsider whether some debug exceptions should
be NMIs, but this will require a significant refactoring, and for now
this should prevent issues with lockdep and RCU.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marins <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201130115950.22492-12-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-11-30 12:11:38 +00:00