83 Commits
Author SHA1 Message Date
Ard BiesheuvelandCatalin Marinas a5baf582f4 arm64/efi: Call EFI runtime services without disabling preemption
The only remaining reason why EFI runtime services are invoked with
preemption disabled is the fact that the mm is swapped out behind the
back of the context switching code.

The kernel no longer disables preemption in kernel_neon_begin().
Furthermore, the EFI spec is being clarified to explicitly state that
only baseline FP/SIMD is permitted in EFI runtime service
implementations, and so the existing kernel mode NEON context switching
code is sufficient to preserve and restore the execution context of an
in-progress EFI runtime service call.

Most EFI calls are made from the efi_rts_wq, which is serviced by a
kthread. As kthreads never return to user space, they usually don't have
an mm, and so we can use the existing infrastructure to swap in the
efi_mm while the EFI call is in progress. This is visible to the
scheduler, which will therefore reactivate the selected mm when
switching out the kthread and back in again.

Given that the EFI spec explicitly permits runtime services to be called
with interrupts enabled, firmware code is already required to tolerate
interruptions. So rather than disable preemption, disable only migration
so that EFI runtime services are less likely to cause scheduling delays.
To avoid potential issues where runtime services are interrupted while
polling the secure firmware for async completions, keep migration
disabled so that a runtime service invocation does not resume on a
different CPU from the one it was started on.

Note, though, that the firmware executes at the same privilege level as
the kernel, and is therefore able to disable interrupts altogether.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-11-11 18:59:22 +00:00
Ard BiesheuvelandCatalin Marinas 6b9c98e657 arm64/efi: Move uaccess en/disable out of efi_set_pgd()
efi_set_pgd() will no longer be called when invoking EFI runtime
services via the efi_rts_wq work queue, but the uaccess en/disable are
still needed when using PAN emulation using TTBR0 switching. So move
these into the callers.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-11-11 18:59:22 +00:00
Ard BiesheuvelandCatalin Marinas 1068cb52e8 arm64/efi: Drop efi_rt_lock spinlock from EFI arch wrapper
Since commit

  5894cf571e ("acpi/prmt: Use EFI runtime sandbox to invoke PRM handlers")

all EFI runtime calls on arm64 are routed via the EFI runtime wrappers,
which are serialized using the efi_runtime_lock semaphore.

This means the efi_rt_lock spinlock in the arm64 arch wrapper code has
become redundant, and can be dropped. For robustness, replace it with an
assert that the EFI runtime lock is in fact held by 'current'.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-11-11 18:59:22 +00:00
Breno LeitaoandWill Deacon 63829521a8 arm64: efi: Remove CONFIG_VMAP_STACK check
Remove the CONFIG_VMAP_STACK check in arm64_efi_rt_init() since
VMAP_STACK is now always enabled on arm64.

The arch_alloc_vmap_stack() call will fail to build if VMAP_STACK
is not set, providing sufficient protection without the explicit
runtime check.

Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20250707-arm64_vmap-v1-2-8de98ca0f91c@debian.org
Signed-off-by: Will Deacon <will@kernel.org>
2025-07-08 13:41:08 +01:00
Breno LeitaoandWill Deacon ef8923e6c0 arm64: efi: Fix KASAN false positive for EFI runtime stack
KASAN reports invalid accesses during arch_stack_walk() for EFI runtime
services due to vmalloc tagging[1]. The EFI runtime stack must be allocated
with KASAN tags reset to avoid false positives.

This patch uses arch_alloc_vmap_stack() instead of __vmalloc_node() for
EFI stack allocation, which internally calls kasan_reset_tag()

The changes ensure EFI runtime stacks are properly sanitized for KASAN
while maintaining functional consistency.

Link: https://lore.kernel.org/all/aFVVEgD0236LdrL6@gmail.com/ [1]
Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20250704-arm_kasan-v2-1-32ebb4fd7607@debian.org
Signed-off-by: Will Deacon <will@kernel.org>
2025-07-04 14:47:06 +01:00
Linus Torvalds 00c010e130 Merge tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of
   creating a pte which addresses the first page in a folio and reduces
   the amount of plumbing which architecture must implement to provide
   this.

 - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of
   largely unrelated folio infrastructure changes which clean things up
   and better prepare us for future work.

 - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory
   Price adds early-init code to prevent x86 from leaving physical
   memory unused when physical address regions are not aligned to memory
   block size.

 - "mm/compaction: allow more aggressive proactive compaction" from
   Michal Clapinski provides some tuning of the (sadly, hard-coded (more
   sadly, not auto-tuned)) thresholds for our invokation of proactive
   compaction. In a simple test case, the reduction of a guest VM's
   memory consumption was dramatic.

 - "Minor cleanups and improvements to swap freeing code" from Kemeng
   Shi provides some code cleaups and a small efficiency improvement to
   this part of our swap handling code.

 - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin
   adds the ability for a ptracer to modify syscalls arguments. At this
   time we can alter only "system call information that are used by
   strace system call tampering, namely, syscall number, syscall
   arguments, and syscall return value.

   This series should have been incorporated into mm.git's "non-MM"
   branch, but I goofed.

 - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from
   Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl
   against /proc/pid/pagemap. This permits CRIU to more efficiently get
   at the info about guard regions.

 - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan
   implements that fix. No runtime effect is expected because
   validate_page_before_insert() happens to fix up this error.

 - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David
   Hildenbrand basically brings uprobe text poking into the current
   decade. Remove a bunch of hand-rolled implementation in favor of
   using more current facilities.

 - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman
   Khandual provides enhancements and generalizations to the pte dumping
   code. This might be needed when 128-bit Page Table Descriptors are
   enabled for ARM.

 - "Always call constructor for kernel page tables" from Kevin Brodsky
   ensures that the ctor/dtor is always called for kernel pgtables, as
   it already is for user pgtables.

   This permits the addition of more functionality such as "insert hooks
   to protect page tables". This change does result in various
   architectures performing unnecesary work, but this is fixed up where
   it is anticipated to occur.

 - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice
   Ryhl adds plumbing to permit Rust access to core MM structures.

 - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo
   Stoakes takes advantage of some VMA merging opportunities which we've
   been missing for 15 years.

 - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from
   SeongJae Park optimizes process_madvise()'s TLB flushing.

   Instead of flushing each address range in the provided iovec, we
   batch the flushing across all the iovec entries. The syscall's cost
   was approximately halved with a microbenchmark which was designed to
   load this particular operation.

 - "Track node vacancy to reduce worst case allocation counts" from
   Sidhartha Kumar makes the maple tree smarter about its node
   preallocation.

   stress-ng mmap performance increased by single-digit percentages and
   the amount of unnecessarily preallocated memory was dramaticelly
   reduced.

 - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes
   a few unnecessary things which Baoquan noted when reading the code.

 - ""Enhance sysfs handling for memory hotplug in weighted interleave"
   from Rakie Kim "enhances the weighted interleave policy in the memory
   management subsystem by improving sysfs handling, fixing memory
   leaks, and introducing dynamic sysfs updates for memory hotplug
   support". Fixes things on error paths which we are unlikely to hit.

 - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory"
   from SeongJae Park introduces new DAMOS quota goal metrics which
   eliminate the manual tuning which is required when utilizing DAMON
   for memory tiering.

 - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He
   provides cleanups and small efficiency improvements which Baoquan
   found via code inspection.

 - "vmscan: enforce mems_effective during demotion" from Gregory Price
   changes reclaim to respect cpuset.mems_effective during demotion when
   possible. because presently, reclaim explicitly ignores
   cpuset.mems_effective when demoting, which may cause the cpuset
   settings to violated.

   This is useful for isolating workloads on a multi-tenant system from
   certain classes of memory more consistently.

 - "Clean up split_huge_pmd_locked() and remove unnecessary folio
   pointers" from Gavin Guo provides minor cleanups and efficiency gains
   in in the huge page splitting and migrating code.

 - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache
   for `struct mem_cgroup', yielding improved memory utilization.

 - "add max arg to swappiness in memory.reclaim and lru_gen" from
   Zhongkun He adds a new "max" argument to the "swappiness=" argument
   for memory.reclaim MGLRU's lru_gen.

   This directs proactive reclaim to reclaim from only anon folios
   rather than file-backed folios.

 - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the
   first step on the path to permitting the kernel to maintain existing
   VMs while replacing the host kernel via file-based kexec. At this
   time only memblock's reserve_mem is preserved.

 - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides
   and uses a smarter way of looping over a pfn range. By skipping
   ranges of invalid pfns.

 - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via
   cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning
   when a task is pinned a single NUMA mode.

   Dramatic performance benefits were seen in some real world cases.

 - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank
   Garg addresses a warning which occurs during memory compaction when
   using JFS.

 - "move all VMA allocation, freeing and duplication logic to mm" from
   Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more
   appropriate mm/vma.c.

 - "mm, swap: clean up swap cache mapping helper" from Kairui Song
   provides code consolidation and cleanups related to the folio_index()
   function.

 - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that.

 - "memcg: Fix test_memcg_min/low test failures" from Waiman Long
   addresses some bogus failures which are being reported by the
   test_memcontrol selftest.

 - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo
   Stoakes commences the deprecation of file_operations.mmap() in favor
   of the new file_operations.mmap_prepare().

   The latter is more restrictive and prevents drivers from messing with
   things in ways which, amongst other problems, may defeat VMA merging.

 - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples
   the per-cpu memcg charge cache from the objcg's one.

   This is a step along the way to making memcg and objcg charging
   NMI-safe, which is a BPF requirement.

 - "mm/damon: minor fixups and improvements for code, tests, and
   documents" from SeongJae Park is yet another batch of miscellaneous
   DAMON changes. Fix and improve minor problems in code, tests and
   documents.

 - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg
   stats to be irq safe. Another step along the way to making memcg
   charging and stats updates NMI-safe, a BPF requirement.

 - "Let unmap_hugepage_range() and several related functions take folio
   instead of page" from Fan Ni provides folio conversions in the
   hugetlb code.

* tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits)
  mm: pcp: increase pcp->free_count threshold to trigger free_high
  mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range()
  mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page
  mm/hugetlb: pass folio instead of page to unmap_ref_private()
  memcg: objcg stock trylock without irq disabling
  memcg: no stock lock for cpu hot-unplug
  memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs
  memcg: make count_memcg_events re-entrant safe against irqs
  memcg: make mod_memcg_state re-entrant safe against irqs
  memcg: move preempt disable to callers of memcg_rstat_updated
  memcg: memcg_rstat_updated re-entrant safe against irqs
  mm: khugepaged: decouple SHMEM and file folios' collapse
  selftests/eventfd: correct test name and improve messages
  alloc_tag: check mem_profiling_support in alloc_tag_init
  Docs/damon: update titles and brief introductions to explain DAMOS
  selftests/damon/_damon_sysfs: read tried regions directories in order
  mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject()
  mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat()
  mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs
  ...
2025-05-31 15:44:16 -07:00
Anshuman KhandualandAndrew Morton dbb9c166a0 arm64/mm: define ptdesc_t
Define ptdesc_t type which describes the basic page table descriptor
layout on arm64 platform.  Subsequently all level specific pxxval_t
descriptors are derived from ptdesc_t thus establishing a common original
format, which can also be appropriate for page table entries, masks and
protection values etc which are used at all page table levels.

Link: https://lkml.kernel.org/r/20250407053113.746295-4-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Suggested-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11 17:48:19 -07:00
Ard BiesheuvelandWill Deacon e04796c8b5 arm64/fpsimd: Avoid unnecessary per-CPU buffers for EFI runtime calls
The EFI specification has some elaborate rules about which runtime
services may be called while another runtime service call is already in
progress. In Linux, however, for simplicity, all EFI runtime service
invocations are serialized via the efi_runtime_lock semaphore.

This implies that calls to the helper pair arch_efi_call_virt_setup()
and arch_efi_call_virt_teardown() are serialized too, and are guaranteed
not to nest.  Furthermore, the arm64 arch code has its own spinlock to
serialize use of the EFI runtime stack, of which only a single instance
exists.

This all means that the FP/SIMD and SVE state preserve/restore logic in
__efi_fpsimd_begin() and __efi_fpsimd_end() are also serialized, and
only a single instance of the associated per-CPU variables can ever be
in use at the same time. There is therefore no need at all for per-CPU
variables here, and they can all be replaced with singleton instances.
This saves a non-trivial amount of memory on systems with many CPUs.

To be more robust against potential future changes in the core EFI code
that may invalidate the reasoning above, move the invocations of
__efi_fpsimd_begin() and __efi_fpsimd_end() into the critical section
covered by the efi_rt_lock spinlock.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250318132421.3155799-2-ardb+git@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2025-04-29 13:13:52 +01:00
Suzuki K PouloseandCatalin Marinas 491db21d82 efi: arm64: Map Device with Prot Shared
Device mappings need to be emulated by the VMM so must be mapped shared
with the host.

Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20241017131434.40935-7-steven.price@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-23 10:19:32 +01:00
Waiman LongandArd Biesheuvel 46e27b9961 efi/arm64: Fix kmemleak false positive in arm64_efi_rt_init()
The kmemleak code sometimes complains about the following leak:

unreferenced object 0xffff8000102e0000 (size 32768):
  comm "swapper/0", pid 1, jiffies 4294937323 (age 71.240s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000db9a88a3>] __vmalloc_node_range+0x324/0x450
    [<00000000ff8903a4>] __vmalloc_node+0x90/0xd0
    [<000000001a06634f>] arm64_efi_rt_init+0x64/0xdc
    [<0000000007826a8d>] do_one_initcall+0x178/0xac0
    [<0000000054a87017>] do_initcalls+0x190/0x1d0
    [<00000000308092d0>] kernel_init_freeable+0x2c0/0x2f0
    [<000000003e7b99e0>] kernel_init+0x28/0x14c
    [<000000002246af5b>] ret_from_fork+0x10/0x20

The memory object in this case is for efi_rt_stack_top and is allocated
in an initcall. So this is certainly a false positive. Mark the object
as not a leak to quash it.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-06-15 10:25:02 +02:00
Kent OverstreetandAndrew Morton 0069455bcb fix missing vmalloc.h includes
Patch series "Memory allocation profiling", v6.

Overview:
Low overhead [1] per-callsite memory allocation profiling. Not just for
debug kernels, overhead low enough to be deployed in production.

Example output:
  root@moria-kvm:~# sort -rn /proc/allocinfo
   127664128    31168 mm/page_ext.c:270 func:alloc_page_ext
    56373248     4737 mm/slub.c:2259 func:alloc_slab_page
    14880768     3633 mm/readahead.c:247 func:page_cache_ra_unbounded
    14417920     3520 mm/mm_init.c:2530 func:alloc_large_system_hash
    13377536      234 block/blk-mq.c:3421 func:blk_mq_alloc_rqs
    11718656     2861 mm/filemap.c:1919 func:__filemap_get_folio
     9192960     2800 kernel/fork.c:307 func:alloc_thread_stack_node
     4206592        4 net/netfilter/nf_conntrack_core.c:2567 func:nf_ct_alloc_hashtable
     4136960     1010 drivers/staging/ctagmod/ctagmod.c:20 [ctagmod] func:ctagmod_start
     3940352      962 mm/memory.c:4214 func:alloc_anon_folio
     2894464    22613 fs/kernfs/dir.c:615 func:__kernfs_new_node
     ...

Usage:
kconfig options:
 - CONFIG_MEM_ALLOC_PROFILING
 - CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT
 - CONFIG_MEM_ALLOC_PROFILING_DEBUG
   adds warnings for allocations that weren't accounted because of a
   missing annotation

sysctl:
  /proc/sys/vm/mem_profiling

Runtime info:
  /proc/allocinfo

Notes:

[1]: Overhead
To measure the overhead we are comparing the following configurations:
(1) Baseline with CONFIG_MEMCG_KMEM=n
(2) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y &&
    CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n)
(3) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y &&
    CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y)
(4) Enabled at runtime (CONFIG_MEM_ALLOC_PROFILING=y &&
    CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n && /proc/sys/vm/mem_profiling=1)
(5) Baseline with CONFIG_MEMCG_KMEM=y && allocating with __GFP_ACCOUNT
(6) Disabled by default (CONFIG_MEM_ALLOC_PROFILING=y &&
    CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=n)  && CONFIG_MEMCG_KMEM=y
(7) Enabled by default (CONFIG_MEM_ALLOC_PROFILING=y &&
    CONFIG_MEM_ALLOC_PROFILING_BY_DEFAULT=y) && CONFIG_MEMCG_KMEM=y

Performance overhead:
To evaluate performance we implemented an in-kernel test executing
multiple get_free_page/free_page and kmalloc/kfree calls with allocation
sizes growing from 8 to 240 bytes with CPU frequency set to max and CPU
affinity set to a specific CPU to minimize the noise. Below are results
from running the test on Ubuntu 22.04.2 LTS with 6.8.0-rc1 kernel on
56 core Intel Xeon:

                        kmalloc                 pgalloc
(1 baseline)            6.764s                  16.902s
(2 default disabled)    6.793s  (+0.43%)        17.007s (+0.62%)
(3 default enabled)     7.197s  (+6.40%)        23.666s (+40.02%)
(4 runtime enabled)     7.405s  (+9.48%)        23.901s (+41.41%)
(5 memcg)               13.388s (+97.94%)       48.460s (+186.71%)
(6 def disabled+memcg)  13.332s (+97.10%)       48.105s (+184.61%)
(7 def enabled+memcg)   13.446s (+98.78%)       54.963s (+225.18%)

Memory overhead:
Kernel size:

   text           data        bss         dec         diff
(1) 26515311	      18890222    17018880    62424413
(2) 26524728	      19423818    16740352    62688898    264485
(3) 26524724	      19423818    16740352    62688894    264481
(4) 26524728	      19423818    16740352    62688898    264485
(5) 26541782	      18964374    16957440    62463596    39183

Memory consumption on a 56 core Intel CPU with 125GB of memory:
Code tags:           192 kB
PageExts:         262144 kB (256MB)
SlabExts:           9876 kB (9.6MB)
PcpuExts:            512 kB (0.5MB)

Total overhead is 0.2% of total memory.

Benchmarks:

Hackbench tests run 100 times:
hackbench -s 512 -l 200 -g 15 -f 25 -P
      baseline       disabled profiling           enabled profiling
avg   0.3543         0.3559 (+0.0016)             0.3566 (+0.0023)
stdev 0.0137         0.0188                       0.0077


hackbench -l 10000
      baseline       disabled profiling           enabled profiling
avg   6.4218         6.4306 (+0.0088)             6.5077 (+0.0859)
stdev 0.0933         0.0286                       0.0489

stress-ng tests:
stress-ng --class memory --seq 4 -t 60
stress-ng --class cpu --seq 4 -t 60
Results posted at: https://evilpiepirate.org/~kent/memalloc_prof_v4_stress-ng/

[2] https://lore.kernel.org/all/20240306182440.2003814-1-surenb@google.com/


This patch (of 37):

The next patch drops vmalloc.h from a system header in order to fix a
circular dependency; this adds it to all the files that were pulling it in
implicitly.

[kent.overstreet@linux.dev: fix arch/alpha/lib/memcpy.c]
  Link: https://lkml.kernel.org/r/20240327002152.3339937-1-kent.overstreet@linux.dev
[surenb@google.com: fix arch/x86/mm/numa_32.c]
  Link: https://lkml.kernel.org/r/20240402180933.1663992-1-surenb@google.com
[kent.overstreet@linux.dev: a few places were depending on sizes.h]
  Link: https://lkml.kernel.org/r/20240404034744.1664840-1-kent.overstreet@linux.dev
[arnd@arndb.de: fix mm/kasan/hw_tags.c]
  Link: https://lkml.kernel.org/r/20240404124435.3121534-1-arnd@kernel.org
[surenb@google.com: fix arc build]
  Link: https://lkml.kernel.org/r/20240405225115.431056-1-surenb@google.com
Link: https://lkml.kernel.org/r/20240321163705.3067592-1-surenb@google.com
Link: https://lkml.kernel.org/r/20240321163705.3067592-2-surenb@google.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andreas Hindborg <a.hindborg@samsung.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: "Björn Roy Baron" <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25 20:55:49 -07:00
Ryan RobertsandAndrew Morton 5a00bfd6a5 arm64/mm: new ptep layer to manage contig bit
Create a new layer for the in-table PTE manipulation APIs.  For now, The
existing API is prefixed with double underscore to become the arch-private
API and the public API is just a simple wrapper that calls the private
API.

The public API implementation will subsequently be used to transparently
manipulate the contiguous bit where appropriate.  But since there are
already some contig-aware users (e.g.  hugetlb, kernel mapper), we must
first ensure those users use the private API directly so that the future
contig-bit manipulations in the public API do not interfere with those
existing uses.

The following APIs are treated this way:

 - ptep_get
 - set_pte
 - set_ptes
 - pte_clear
 - ptep_get_and_clear
 - ptep_test_and_clear_young
 - ptep_clear_flush_young
 - ptep_set_wrprotect
 - ptep_set_access_flags

Link: https://lkml.kernel.org/r/20240215103205.2607016-11-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:27:18 -08:00
Ryan RobertsandAndrew Morton 532736558e arm64/mm: convert READ_ONCE(*ptep) to ptep_get(ptep)
There are a number of places in the arch code that read a pte by using the
READ_ONCE() macro.  Refactor these call sites to instead use the
ptep_get() helper, which itself is a READ_ONCE().  Generated code should
be the same.

This will benefit us when we shortly introduce the transparent contpte
support.  In this case, ptep_get() will become more complex so we now have
all the code abstracted through it.

Link: https://lkml.kernel.org/r/20240215103205.2607016-8-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Barry Song <21cnbao@gmail.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:27:18 -08:00
Linus Torvalds 1f24458a10 Merge tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty and serial updates from Greg KH:
 "Here is the big set of tty/serial driver changes for 6.7-rc1. Included
  in here are:

   - console/vgacon cleanups and removals from Arnd

   - tty core and n_tty cleanups from Jiri

   - lots of 8250 driver updates and cleanups

   - sc16is7xx serial driver updates

   - dt binding updates

   - first set of port lock wrapers from Thomas for the printk fixes
     coming in future releases

   - other small serial and tty core cleanups and updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (193 commits)
  serdev: Replace custom code with device_match_acpi_handle()
  serdev: Simplify devm_serdev_device_open() function
  serdev: Make use of device_set_node()
  tty: n_gsm: add copyright Siemens Mobility GmbH
  tty: n_gsm: fix race condition in status line change on dead connections
  serial: core: Fix runtime PM handling for pending tx
  vgacon: fix mips/sibyte build regression
  dt-bindings: serial: drop unsupported samsung bindings
  tty: serial: samsung: drop earlycon support for unsupported platforms
  tty: 8250: Add note for PX-835
  tty: 8250: Fix IS-200 PCI ID comment
  tty: 8250: Add Brainboxes Oxford Semiconductor-based quirks
  tty: 8250: Add support for Intashield IX cards
  tty: 8250: Add support for additional Brainboxes PX cards
  tty: 8250: Fix up PX-803/PX-857
  tty: 8250: Fix port count of PX-257
  tty: 8250: Add support for Intashield IS-100
  tty: 8250: Add support for Brainboxes UP cards
  tty: 8250: Add support for additional Brainboxes UC cards
  tty: 8250: Remove UC-257 and UC-431
  ...
2023-11-03 15:44:25 -10:00
Arnd BergmannandGreg Kroah-Hartman b8466fe82b efi: move screen_info into efi init code
After the vga console no longer relies on global screen_info, there are
only two remaining use cases:

 - on the x86 architecture, it is used for multiple boot methods
   (bzImage, EFI, Xen, kexec) to commucate the initial VGA or framebuffer
   settings to a number of device drivers.

 - on other architectures, it is only used as part of the EFI stub,
   and only for the three sysfb framebuffers (simpledrm, simplefb, efifb).

Remove the duplicate data structure definitions by moving it into the
efi-init.c file that sets it up initially for the EFI case, leaving x86
as an exception that retains its own definition for non-EFI boots.

The added #ifdefs here are optional, I added them to further limit the
reach of screen_info to configurations that have at least one of the
users enabled.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231017093947.3627976-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-17 16:33:39 +02:00
Mark RutlandandCatalin Marinas bbbb65770b arm64: Avoid cpus_have_const_cap() for ARM64_HAS_BTI
In system_supports_bti() we use cpus_have_const_cap() to check for
ARM64_HAS_BTI, but this is not necessary and alternative_has_cap_*() or
cpus_have_final_*cap() would be preferable.

For historical reasons, cpus_have_const_cap() is more complicated than
it needs to be. Before cpucaps are finalized, it will perform a bitmap
test of the system_cpucaps bitmap, and once cpucaps are finalized it
will use an alternative branch. This used to be necessary to handle some
race conditions in the window between cpucap detection and the
subsequent patching of alternatives and static branches, where different
branches could be out-of-sync with one another (or w.r.t. alternative
sequences). Now that we use alternative branches instead of static
branches, these are all patched atomically w.r.t. one another, and there
are only a handful of cases that need special care in the window between
cpucap detection and alternative patching.

Due to the above, it would be nice to remove cpus_have_const_cap(), and
migrate callers over to alternative_has_cap_*(), cpus_have_final_cap(),
or cpus_have_cap() depending on when their requirements. This will
remove redundant instructions and improve code generation, and will make
it easier to determine how each callsite will behave before, during, and
after alternative patching.

When CONFIG_ARM64_BTI_KERNEL=y, the ARM64_HAS_BTI cpucap is a strict
boot cpu feature which is detected and patched early on the boot cpu.
All uses guarded by CONFIG_ARM64_BTI_KERNEL happen after the boot CPU
has detected ARM64_HAS_BTI and patched boot alternatives, and hence can
safely use alternative_has_cap_*() or cpus_have_final_boot_cap().

Regardless of CONFIG_ARM64_BTI_KERNEL, all other uses of ARM64_HAS_BTI
happen after system capabilities have been finalized and alternatives
have been patched. Hence these can safely use alternative_has_cap_*) or
cpus_have_final_cap().

This patch splits system_supports_bti() into system_supports_bti() and
system_supports_bti_kernel(), with the former handling where the cpucap
affects userspace functionality, and ther latter handling where the
cpucap affects kernel functionality. The use of cpus_have_const_cap() is
replaced by cpus_have_final_cap() in cpus_have_const_cap, and
cpus_have_final_boot_cap() in system_supports_bti_kernel(). This will
avoid generating code to test the system_cpucaps bitmap and should be
better for all subsequent calls at runtime. The use of
cpus_have_final_cap() and cpus_have_final_boot_cap() will make it easier
to spot if code is chaanged such that these run before the ARM64_HAS_BTI
cpucap is guaranteed to have been finalized.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2023-10-16 14:17:04 +01:00
Linus Torvalds 461f35f014 Merge tag 'drm-next-2023-08-30' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie:
 "The drm core grew a new generic gpu virtual address manager, and new
  execution locking helpers. These are used by nouveau now to provide
  uAPI support for the userspace Vulkan driver. AMD had a bunch of new
  IP core support, loads of refactoring around fbdev, but mostly just
  the usual amount of stuff across the board.

  core:
   - fix gfp flags in drmm_kmalloc

  gpuva:
   - add new generic GPU VA manager (for nouveau initially)

  syncobj:
   - add new DRM_IOCTL_SYNCOBJ_EVENTFD ioctl

  dma-buf:
   - acquire resv lock for mmap() in exporters
   - support dma-buf self import automatically
   - docs fixes

  backlight:
   - fix fbdev interactions

  atomic:
   - improve logging

  prime:
   - remove struct gem_prim_mmap plus driver updates

  gem:
   - drm_exec: add locking over multiple GEM objects
   - fix lockdep checking

  fbdev:
   - make fbdev userspace interfaces optional
   - use linux device instead of fbdev device
   - use deferred i/o helper macros in various drivers
   - Make FB core selectable without drivers
   - Remove obsolete flags FBINFO_DEFAULT and FBINFO_FLAG_DEFAULT
   - Add helper macros and Kconfig tokens for DMA-allocated framebuffer

  ttm:
   - support init_on_free
   - swapout fixes

  panel:
   - panel-edp: Support AUO B116XAB01.4
   - Support Visionox R66451 plus DT bindings
   - ld9040:
      - Backlight support
      - magic improved
      - Kconfig fix
   - Convert to of_device_get_match_data()
   - Fix Kconfig dependencies
   - simple:
      - Set bpc value to fix warning
      - Set connector type for AUO T215HVN01
      - Support Innolux G156HCE-L01 plus DT bindings
   - ili9881: Support TDO TL050HDV35 LCD panel plus DT bindings
   - startek: Support KD070FHFID015 MIPI-DSI panel plus DT bindings
   - sitronix-st7789v:
      - Support Inanbo T28CP45TN89 plus DT bindings
      - Support EDT ET028013DMA plus DT bindings
      - Various cleanups
   - edp: Add timings for N140HCA-EAC
   - Allow panels and touchscreens to power sequence together
   - Fix Innolux G156HCE-L01 LVDS clock

  bridge:
   - debugfs for chains support
   - dw-hdmi:
      - Improve support for YUV420 bus format
      - CEC suspend/resume
      - update EDID on HDMI detect
   - dw-mipi-dsi: Fix enable/disable of DSI controller
   - lt9611uxc: Use MODULE_FIRMWARE()
   - ps8640: Remove broken EDID code
   - samsung-dsim: Fix command transfer
   - tc358764:
      - Handle HS/VS polarity
      - Use BIT() macro
      - Various cleanups
   - adv7511: Fix low refresh rate
   - anx7625:
      - Switch to macros instead of hardcoded values
      - locking fixes
   - tc358767: fix hardware delays
   - sitronix-st7789v:
      - Support panel orientation
      - Support rotation property
      - Add support for Jasonic JT240MHQS-HWT-EK-E3 plus DT bindings

  amdgpu:
   - SDMA 6.1.0 support
   - HDP 6.1 support
   - SMUIO 14.0 support
   - PSP 14.0 support
   - IH 6.1 support
   - Lots of checkpatch cleanups
   - GFX 9.4.3 updates
   - Add USB PD and IFWI flashing documentation
   - GPUVM updates
   - RAS fixes
   - DRR fixes
   - FAMS fixes
   - Virtual display fixes
   - Soft IH fixes
   - SMU13 fixes
   - Rework PSP firmware loading for other IPs
   - Kernel doc fixes
   - DCN 3.0.1 fixes
   - LTTPR fixes
   - DP MST fixes
   - DCN 3.1.6 fixes
   - SMU 13.x fixes
   - PSP 13.x fixes
   - SubVP fixes
   - GC 9.4.3 fixes
   - Display bandwidth calculation fixes
   - VCN4 secure submission fixes
   - Allow building DC on RISC-V
   - Add visible FB info to bo_print_info
   - HBR3 fixes
   - GFX9 MCBP fix
   - GMC10 vmhub index fix
   - GMC11 vmhub index fix
   - Create a new doorbell manager
   - SR-IOV fixes
   - initial freesync panel replay support
   - revert zpos properly until igt regression is fixeed
   - use TTM to manage doorbell BAR
   - Expose both current and average power via hwmon if supported

  amdkfd:
   - Cleanup CRIU dma-buf handling
   - Use KIQ to unmap HIQ
   - GFX 9.4.3 debugger updates
   - GFX 9.4.2 debugger fixes
   - Enable cooperative groups fof gfx11
   - SVM fixes
   - Convert older APUs to use dGPU path like newer APUs
   - Drop IOMMUv2 path as it is no longer used
   - TBA fix for aldebaran

  i915:
   - ICL+ DSI modeset sequence
   - HDCP improvements
   - MTL display fixes and cleanups
   - HSW/BDW PSR1 restored
   - Init DDI ports in VBT order
   - General display refactors
   - Start using plane scale factor for relative data rate
   - Use shmem for dpt objects
   - Expose RPS thresholds in sysfs
   - Apply GuC SLPC min frequency softlimit correctly
   - Extend Wa_14015795083 to TGL, RKL, DG1 and ADL
   - Fix a VMA UAF for multi-gt platform
   - Do not use stolen on MTL due to HW bug
   - Check HuC and GuC version compatibility on MTL
   - avoid infinite GPU waits due to premature release of request memory
   - Fixes and updates for GSC memory allocation
   - Display SDVO fixes
   - Take stolen handling out of FBC code
   - Make i915_coherent_map_type GT-centric
   - Simplify shmem_create_from_object map_type

  msm:
   - SM6125 MDSS support
   - DPU: SM6125 DPU support
   - DSI: runtime PM support, burst mode support
   - DSI PHY: SM6125 support in 14nm DSI PHY driver
   - GPU: prepare for a7xx
   - fix a690 firmware
   - disable relocs on a6xx and newer

  radeon:
   - Lots of checkpatch cleanups

  ast:
   - improve device-model detection
   - Represent BMV as virtual connector
   - Report DP connection status

  nouveau:
   - add new exec/bind interface to support Vulkan
   - document some getparam ioctls
   - improve VRAM detection
   - various fixes/cleanups
   - workraound DPCD issues

  ivpu:
   - MMU updates
   - debugfs support
   - Support vpu4

  virtio:
   - add sync object support

  atmel-hlcdc:
   - Support inverted pixclock polarity

  etnaviv:
   - runtime PM cleanups
   - hang handling fixes

  exynos:
   - use fbdev DMA helpers
   - fix possible NULL ptr dereference

  komeda:
   - always attach encoder

  omapdrm:
   - use fbdev DMA helpers
ingenic:
   - kconfig regmap fixes

  loongson:
   - support display controller

  mediatek:
   - Small mtk-dpi cleanups
   - DisplayPort: support eDP and aux-bus
   - Fix coverity issues
   - Fix potential memory leak if vmap() fail

  mgag200:
   - minor fixes

  mxsfb:
   - support disabling overlay planes

  panfrost:
   - fix sync in IRQ handling

  ssd130x:
   - Support per-controller default resolution plus DT bindings
   - Reduce memory-allocation overhead
   - Improve intermediate buffer size computation
   - Fix allocation of temporary buffers
   - Fix pitch computation
   - Fix shadow plane allocation

  tegra:
   - use fbdev DMA helpers
   - Convert to devm_platform_ioremap_resource()
   - support bridge/connector
   - enable PM

  tidss:
   - Support TI AM625 plus DT bindings
   - Implement new connector model plus driver updates

  vkms:
   - improve write back support
   - docs fixes
   - support gamma LUT

  zynqmp-dpsub:
   - misc fixes"

* tag 'drm-next-2023-08-30' of git://anongit.freedesktop.org/drm/drm: (1327 commits)
  drm/gpuva_mgr: remove unused prev pointer in __drm_gpuva_sm_map()
  drm/tests/drm_kunit_helpers: Place correct function name in the comment header
  drm/nouveau: uapi: don't pass NO_PREFETCH flag implicitly
  drm/nouveau: uvmm: fix unset region pointer on remap
  drm/nouveau: sched: avoid job races between entities
  drm/i915: Fix HPD polling, reenabling the output poll work as needed
  drm: Add an HPD poll helper to reschedule the poll work
  drm/i915: Fix TLB-Invalidation seqno store
  drm/ttm/tests: Fix type conversion in ttm_pool_test
  drm/msm/a6xx: Bail out early if setting GPU OOB fails
  drm/msm/a6xx: Move LLC accessors to the common header
  drm/msm/a6xx: Introduce a6xx_llc_read
  drm/ttm/tests: Require MMU when testing
  drm/panel: simple: Fix Innolux G156HCE-L01 LVDS clock
  Revert "Revert "drm/amdgpu/display: change pipe policy for DCN 2.0""
  drm/amdgpu: Add memory vendor information
  drm/amd: flush any delayed gfxoff on suspend entry
  drm/amdgpu: skip fence GFX interrupts disable/enable for S0ix
  drm/amdgpu: Remove gfxoff check in GFX v9.4.3
  drm/amd/pm: Update pci link speed for smu v13.0.6
  ...
2023-08-30 13:34:34 -07:00
Ard Biesheuvel c37ce23591 efi/arm64: Move EFI runtime call setup/teardown helpers out of line
Only the arch_efi_call_virt() macro that some architectures override
needs to be a macro, given that it is variadic and encapsulates calls
via function pointers that have different prototypes.

The associated setup and teardown code are not special in this regard,
and don't need to be instantiated at each call site. So turn them into
ordinary C functions and move them out of line.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-08-21 17:49:16 +02:00
Thomas Zimmermann 8b0d13545b efi: Do not include <linux/screen_info.h> from EFI header
The header file <linux/efi.h> does not need anything from
<linux/screen_info.h>. Declare struct screen_info and remove
the include statements. Update a number of source files that
require struct screen_info's definition.

v2:
	* update loongarch (Jingfeng)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230706104852.27451-2-tzimmermann@suse.de
2023-07-08 20:26:36 +02:00
Linus Torvalds 06e1a81c48 Merge tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI updates from Ard Biesheuvel:
 "A healthy mix of EFI contributions this time:

   - Performance tweaks for efifb earlycon (Andy)

   - Preparatory refactoring and cleanup work in the efivar layer, which
     is needed to accommodate the Snapdragon arm64 laptops that expose
     their EFI variable store via a TEE secure world API (Johan)

   - Enhancements to the EFI memory map handling so that Xen dom0 can
     safely access EFI configuration tables (Demi Marie)

   - Wire up the newly introduced IBT/BTI flag in the EFI memory
     attributes table, so that firmware that is generated with ENDBR/BTI
     landing pads will be mapped with enforcement enabled

   - Clean up how we check and print the EFI revision exposed by the
     firmware

   - Incorporate EFI memory attributes protocol definition and wire it
     up in the EFI zboot code (Evgeniy)

     This ensures that these images can execute under new and stricter
     rules regarding the default memory permissions for EFI page
     allocations (More work is in progress here)

   - CPER header cleanup (Dan Williams)

   - Use a raw spinlock to protect the EFI runtime services stack on
     arm64 to ensure the correct semantics under -rt (Pierre)

   - EFI framebuffer quirk for Lenovo Ideapad (Darrell)"

* tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits)
  firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3
  arm64: efi: Make efi_rt_lock a raw_spinlock
  efi: Add mixed-mode thunk recipe for GetMemoryAttributes
  efi: x86: Wire up IBT annotation in memory attributes table
  efi: arm64: Wire up BTI annotation in memory attributes table
  efi: Discover BTI support in runtime services regions
  efi/cper, cxl: Remove cxl_err.h
  efi: Use standard format for printing the EFI revision
  efi: Drop minimum EFI version check at boot
  efi: zboot: Use EFI protocol to remap code/data with the right attributes
  efi/libstub: Add memory attribute protocol definitions
  efi: efivars: prevent double registration
  efi: verify that variable services are supported
  efivarfs: always register filesystem
  efi: efivars: add efivars printk prefix
  efi: Warn if trying to reserve memory under Xen
  efi: Actually enable the ESRT under Xen
  efi: Apply allowlist to EFI configuration tables when running under Xen
  efi: xen: Implement memory descriptor lookup based on hypercall
  efi: memmap: Disregard bogus entries instead of returning them
  ...
2023-02-23 14:41:48 -08:00
Pierre GondoisandArd Biesheuvel 0e68b5517d arm64: efi: Make efi_rt_lock a raw_spinlock
Running a rt-kernel base on 6.2.0-rc3-rt1 on an Ampere Altra outputs
the following:
  BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
  in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9, name: kworker/u320:0
  preempt_count: 2, expected: 0
  RCU nest depth: 0, expected: 0
  3 locks held by kworker/u320:0/9:
  #0: ffff3fff8c27d128 ((wq_completion)efi_rts_wq){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41)
  #1: ffff80000861bdd0 ((work_completion)(&efi_rts_work.work)){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41)
  #2: ffffdf7e1ed3e460 (efi_rt_lock){+.+.}-{3:3}, at: efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101)
  Preemption disabled at:
  efi_virtmap_load (./arch/arm64/include/asm/mmu_context.h:248)
  CPU: 0 PID: 9 Comm: kworker/u320:0 Tainted: G        W          6.2.0-rc3-rt1
  Hardware name: WIWYNN Mt.Jade Server System B81.03001.0005/Mt.Jade Motherboard, BIOS 1.08.20220218 (SCP: 1.08.20220218) 2022/02/18
  Workqueue: efi_rts_wq efi_call_rts
  Call trace:
  dump_backtrace (arch/arm64/kernel/stacktrace.c:158)
  show_stack (arch/arm64/kernel/stacktrace.c:165)
  dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
  dump_stack (lib/dump_stack.c:114)
  __might_resched (kernel/sched/core.c:10134)
  rt_spin_lock (kernel/locking/rtmutex.c:1769 (discriminator 4))
  efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101)
  [...]

This seems to come from commit ff7a167961 ("arm64: efi: Execute
runtime services from a dedicated stack") which adds a spinlock. This
spinlock is taken through:
efi_call_rts()
\-efi_call_virt()
  \-efi_call_virt_pointer()
    \-arch_efi_call_virt_setup()

Make 'efi_rt_lock' a raw_spinlock to avoid being preempted.

[ardb: The EFI runtime services are called with a different set of
       translation tables, and are permitted to use the SIMD registers.
       The context switch code preserves/restores neither, and so EFI
       calls must be made with preemption disabled, rather than only
       disabling migration.]

Fixes: ff7a167961 ("arm64: efi: Execute runtime services from a dedicated stack")
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Cc: <stable@vger.kernel.org> # v6.1+
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-02-19 14:40:35 +01:00
Ard Biesheuvel 1d959312e2 efi: arm64: Wire up BTI annotation in memory attributes table
UEFI v2.10 extends the EFI memory attributes table with a flag that
indicates whether or not all RuntimeServicesCode regions were
constructed with BTI landing pads, permitting the OS to map these
regions with BTI restrictions enabled.

So let's take this into account on arm64.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will@kernel.org>
2023-02-09 17:39:16 +01:00
Ard Biesheuvel cf1d2ffcc6 efi: Discover BTI support in runtime services regions
Add the generic plumbing to detect whether or not the runtime code
regions were constructed with BTI/IBT landing pads by the firmware,
permitting the OS to enable enforcement when mapping these regions into
the OS's address space.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
2023-02-04 09:19:02 +01:00
Ard Biesheuvel 8a9a1a1873 arm64: efi: Avoid workqueue to check whether EFI runtime is live
Comparing current_work() against efi_rts_work.work is sufficient to
decide whether current is currently running EFI runtime services code at
any level in its call stack.

However, there are other potential users of the EFI runtime stack, such
as the ACPI subsystem, which may invoke efi_call_virt_pointer()
directly, and so any sync exceptions occurring in firmware during those
calls are currently misidentified.

So instead, let's check whether the stashed value of the thread stack
pointer points into current's thread stack. This can only be the case if
current was interrupted while running EFI runtime code. Note that this
implies that we should clear the stashed value after switching back, to
avoid false positives.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-01-16 15:27:31 +01:00
Ard Biesheuvel e8dfdf3162 arm64: efi: Recover from synchronous exceptions occurring in firmware
Unlike x86, which has machinery to deal with page faults that occur
during the execution of EFI runtime services, arm64 has nothing like
that, and a synchronous exception raised by firmware code brings down
the whole system.

With more EFI based systems appearing that were not built to run Linux
(such as the Windows-on-ARM laptops based on Qualcomm SOCs), as well as
the introduction of PRM (platform specific firmware routines that are
callable just like EFI runtime services), we are more likely to run into
issues of this sort, and it is much more likely that we can identify and
work around such issues if they don't bring down the system entirely.

Since we already use a EFI runtime services call wrapper in assembler,
we can quite easily add some code that captures the execution state at
the point where the call is made, allowing us to revert to this state
and proceed execution if the call triggered a synchronous exception.

Given that the kernel and the firmware don't share any data structures
that could end up in an indeterminate state, we can happily continue
running, as long as we mark the EFI runtime services as unavailable from
that point on.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2022-12-08 18:33:34 +01:00