linux-toradex.git/arch/s390/include/asm, branch v6.7

posix-timers: Get rid of [COMPAT_]SYS_NI() uses

2023-12-21T05:30:27+00:00

Only the posix timer system calls use this (when the posix timer support
is disabled, which does not actually happen in any normal case), because
they had debug code to print out a warning about missing system calls.

Get rid of that special case, and just use the standard COND_SYSCALL
interface that creates weak system call stubs that return -ENOSYS for
when the system call does not exist.

This fixes a kCFI issue with the SYS_NI() hackery:

  CFI failure at int80_emulation+0x67/0xb0 (target: sys_ni_posix_timers+0x0/0x70; expected type: 0xb02b34d9)
  WARNING: CPU: 0 PID: 48 at int80_emulation+0x67/0xb0

Reported-by: kernel test robot 
Reviewed-by: Sami Tolvanen 
Tested-by: Sami Tolvanen 
Cc: Thomas Gleixner 
Cc: Dave Hansen 
Cc: Borislav Petkov 
Signed-off-by: Linus Torvalds

s390/vx: fix save/restore of fpu kernel context

2023-12-18T09:53:41+00:00

The KERNEL_FPR mask only contains a flag for the first eight vector
registers. However floating point registers overlay parts of the first
sixteen vector registers.

This could lead to vector register corruption if a kernel fpu context uses
any of the vector registers 8 to 15 and is interrupted or calls a
KERNEL_FPR context. If that context uses also vector registers 8 to 15,
their contents will be corrupted on return.

Luckily this is currently not a real bug, since the kernel has only one
KERNEL_FPR user with s390_adjust_jiffies() and it is only using floating
point registers 0 to 2.

Fix this by using the correct bits for KERNEL_FPR.

Fixes: 7f79695cc1b6 ("s390/fpu: improve kernel_fpu_[begin|end]")
Signed-off-by: Heiko Carstens 
Reviewed-by: Hendrik Brueckner 
Signed-off-by: Alexander Gordeev

s390: remove odd comment

2023-11-22T12:55:13+00:00

In the meantime hopefully most people got used to forward
declarations, therefore remove the explanation.

Signed-off-by: Heiko Carstens 
Signed-off-by: Alexander Gordeev

kprobes: unify kprobes_exceptions_nofify() prototypes

2023-11-10T10:59:05+00:00

Most architectures that support kprobes declare this function in their
own asm/kprobes.h header and provide an override, but some are missing
the prototype, which causes a warning for the __weak stub implementation:

kernel/kprobes.c:1865:12: error: no previous prototype for 'kprobe_exceptions_notify' [-Werror=missing-prototypes]
 1865 | int __weak kprobe_exceptions_notify(struct notifier_block *self,

Move the prototype into linux/kprobes.h so it is visible to all
the definitions.

Link: https://lore.kernel.org/all/20231108125843.3806765-4-arnd@kernel.org/

Acked-by: Masami Hiramatsu (Google) 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Masami Hiramatsu (Google)

Merge tag 'iommu-updates-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2023-11-09T21:37:28+00:00

Pull iommu updates from Joerg Roedel:
 "Core changes:
   - Make default-domains mandatory for all IOMMU drivers
   - Remove group refcounting
   - Add generic_single_device_group() helper and consolidate drivers
   - Cleanup map/unmap ops
   - Scaling improvements for the IOVA rcache depot
   - Convert dart & iommufd to the new domain_alloc_paging()

  ARM-SMMU:
   - Device-tree binding update:
       - Add qcom,sm7150-smmu-v2 for Adreno on SM7150 SoC
   - SMMUv2:
       - Support for Qualcomm SDM670 (MDSS) and SM7150 SoCs
   - SMMUv3:
       - Large refactoring of the context descriptor code to move the CD
         table into the master, paving the way for '->set_dev_pasid()'
         support on non-SVA domains
   - Minor cleanups to the SVA code

  Intel VT-d:
   - Enable debugfs to dump domain attached to a pasid
   - Remove an unnecessary inline function

  AMD IOMMU:
   - Initial patches for SVA support (not complete yet)

  S390 IOMMU:
   - DMA-API conversion and optimized IOTLB flushing

  And some smaller fixes and improvements"

* tag 'iommu-updates-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (102 commits)
  iommu/dart: Remove the force_bypass variable
  iommu/dart: Call apple_dart_finalize_domain() as part of alloc_paging()
  iommu/dart: Convert to domain_alloc_paging()
  iommu/dart: Move the blocked domain support to a global static
  iommu/dart: Use static global identity domains
  iommufd: Convert to alloc_domain_paging()
  iommu/vt-d: Use ops->blocked_domain
  iommu/vt-d: Update the definition of the blocking domain
  iommu: Move IOMMU_DOMAIN_BLOCKED global statics to ops->blocked_domain
  Revert "iommu/vt-d: Remove unused function"
  iommu/amd: Remove DMA_FQ type from domain allocation path
  iommu: change iommu_map_sgtable to return signed values
  iommu/virtio: Add __counted_by for struct viommu_request and use struct_size()
  iommu/vt-d: debugfs: Support dumping a specified page table
  iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid}
  iommu/vt-d: debugfs: Dump entry pointing to huge page
  iommu/vt-d: Remove unused function
  iommu/arm-smmu-v3-sva: Remove bond refcount
  iommu/arm-smmu-v3-sva: Remove unused iommu_sva handle
  iommu/arm-smmu-v3: Rename cdcfg to cd_table
  ...

s390/mm: make pte_free_tlb() similar to pXd_free_tlb()

2023-11-05T21:34:58+00:00

Make pte_free_tlb() look similar to pXd_free_tlb() family
functions.

Reviewed-by: Heiko Carstens 
Reviewed-by: Gerald Schaefer 
Signed-off-by: Alexander Gordeev 
Signed-off-by: Vasily Gorbik

s390/mm: use full 4KB page for 2KB PTE

2023-11-05T21:34:58+00:00

Cease using 4KB pages to host two 2KB PTEs. That greatly
simplifies the memory management code at the expense of
page tables memory footprint.

Instead of two PTEs per 4KB page use only upper half of
the parent page for a single PTE. With that the list of
half-used pages pgtable_list becomes unneeded.

Further, the upper byte of the parent page _refcount
counter does not need to be used for fragments tracking
and could be left alone.

Commit 8211dad62798 ("s390: add pte_free_defer() for
pgtables sharing page") introduced the use of PageActive
flag to coordinate a deferred free with 2KB page table
fragments tracking. Since there is no tracking anymore,
there is no need for using PageActive flag.

Reviewed-by: Heiko Carstens 
Reviewed-by: Gerald Schaefer 
Signed-off-by: Alexander Gordeev 
Signed-off-by: Vasily Gorbik

s390/cmma: rework no-dat handling

2023-11-05T21:34:58+00:00

Rework the way physical pages are set no-dat / dat:

The old way is:

- Rely on that all pages are initially marked "dat"
- Allocate page tables for the kernel mapping
- Enable dat
- Walk the whole kernel mapping and set PG_arch_1 bit in all struct pages
  that belong to pages of kernel page tables
- Walk all struct pages and test and clear the PG_arch_1 bit. If the bit is
  not set, set the page state to no-dat
- For all subsequent page table allocations, set the page state to dat
  (remove the no-dat state) on allocation time

Change this rather complex logic to a simpler approach:

- Set the whole physical memory (all pages) to "no-dat"
- Explicitly set those page table pages to "dat" which are part of the
  kernel image (e.g. swapper_pg_dir)
- For all subsequent page table allocations, set the page state to dat
  (remove the no-dat state) on allocation time

In result the code is simpler, and this also allows to get rid of one
odd usage of the PG_arch_1 bit.

Reviewed-by: Claudio Imbrenda 
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390/cmma: move arch_set_page_dat() to header file

2023-11-05T21:34:58+00:00

In order to be usable for early boot code move the simple
arch_set_page_dat() function to header file, and add its counter-part
arch_set_page_nodat(). Also change the parameters, and the function name
slightly.

This is required since there aren't any struct pages available in early
boot code, and renaming of functions is done to make sure that all users
are converted to the new API.

Instead of a pointer to a struct page a virtual address is passed, and
instead of an order the number of pages for which the page state needs be
set.

Reviewed-by: Claudio Imbrenda 
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390/cmma: move set_page_stable() and friends to header file

2023-11-05T21:34:58+00:00

In order to be usable for early boot code move the simple set_page_xxx()
function to header file. Also change the parameters, and the function names
slightly.

This is required since there aren't any struct pages available in early
boot code, and renaming of functions is done to make sure that all users
are converted to the new API.

Instead of a pointer to a struct page a virtual address is passed, and
instead of an order the number of pages for which the page state needs be
set.

Reviewed-by: Claudio Imbrenda 
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik