linux-stable.git/arch/mips/include/asm, branch linux-6.14.y

MIPS: Use arch specific syscall name match function

2025-05-29T09:13:11+00:00

[ Upstream commit 756276ce78d5624dc814f9d99f7d16c8fd51076e ]

On MIPS system, most of the syscall function name begin with prefix
sys_. Some syscalls are special such as clone/fork, function name of
these begin with __sys_. Since scratch registers need be saved in
stack when these system calls happens.

With ftrace system call method, system call functions are declared with
SYSCALL_DEFINEx, metadata of the system call symbol name begins with
sys_. Here mips specific function arch_syscall_match_sym_name is used to
compare function name between sys_call_table[] and metadata of syscall
symbol.

Signed-off-by: Bibo Mao 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: Fix MAX_REG_OFFSET

2025-05-18T06:26:07+00:00

[ Upstream commit c44572e0cc13c9afff83fd333135a0aa9b27ba26 ]

Fix MAX_REG_OFFSET to point to the last register in 'pt_regs' and not to
the marker itself, which could allow regs_get_register() to return an
invalid offset.

Fixes: 40e084a506eb ("MIPS: Add uprobes support.")
Suggested-by: Maciej W. Rozycki 
Signed-off-by: Thorsten Blum 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: cm: Fix warning if MIPS_CM is disabled

2025-05-02T06:02:14+00:00

commit b73c3ccdca95c237750c981054997c71d33e09d7 upstream.

Commit e27fbe16af5c ("MIPS: cm: Detect CM quirks from device tree")
introduced

arch/mips/include/asm/mips-cm.h:119:13: error: ‘mips_cm_update_property’
	defined but not used [-Werror=unused-function]

Fix this by making empty function implementation inline

Fixes: e27fbe16af5c ("MIPS: cm: Detect CM quirks from device tree")
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Greg Kroah-Hartman

MIPS: cm: Detect CM quirks from device tree

2025-05-02T06:01:56+00:00

[ Upstream commit e27fbe16af5cfc40639de4ced67d1a866a1953e9 ]

Some information that should be retrieved at runtime for the Coherence
Manager can be either absent or wrong. This patch allows checking if
some of this information is available from the device tree and updates
the internal variable accordingly.

For now, only the compatible string associated with the broken HCI is
being retrieved.

Signed-off-by: Gregory CLEMENT 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: ds1287: Match ds1287_set_base_clock() function types

2025-04-25T08:51:21+00:00

commit a759109b234385b74d2f5f4c86b5f59b3201ec12 upstream.

Synchronize the declaration of ds1287_set_base_clock() between
cevt-ds1287.c and ds1287.h.

Fix follow error with gcc-14 when -Werror:

arch/mips/kernel/cevt-ds1287.c:21:5: error: conflicting types for ‘ds1287_set_base_clock’; have ‘int(unsigned int)’
   21 | int ds1287_set_base_clock(unsigned int hz)
      |     ^~~~~~~~~~~~~~~~~~~~~
In file included from arch/mips/kernel/cevt-ds1287.c:13:
./arch/mips/include/asm/ds1287.h:11:13: note: previous declaration of ‘ds1287_set_base_clock’ with type ‘void(unsigned int)’
   11 | extern void ds1287_set_base_clock(unsigned int clock);
      |             ^~~~~~~~~~~~~~~~~~~~~
make[7]: *** [scripts/Makefile.build:207: arch/mips/kernel/cevt-ds1287.o] Error 1
make[6]: *** [scripts/Makefile.build:465: arch/mips/kernel] Error 2
make[6]: *** Waiting for unfinished jobs....

Signed-off-by: WangYuli 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Greg Kroah-Hartman

mm: hugetlb: Add huge page size param to huge_ptep_get_and_clear()

2025-02-27T17:40:57+00:00

In order to fix a bug, arm64 needs to be told the size of the huge page
for which the huge_pte is being cleared in huge_ptep_get_and_clear().
Provide for this by adding an `unsigned long sz` parameter to the
function. This follows the same pattern as huge_pte_clear() and
set_huge_pte_at().

This commit makes the required interface modifications to the core mm as
well as all arches that implement this function (arm64, loongarch, mips,
parisc, powerpc, riscv, s390, sparc). The actual arm64 bug will be fixed
in a separate commit.

Cc: stable@vger.kernel.org
Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit")
Acked-by: David Hildenbrand 
Reviewed-by: Alexandre Ghiti  # riscv
Reviewed-by: Christophe Leroy 
Reviewed-by: Catalin Marinas 
Reviewed-by: Anshuman Khandual 
Signed-off-by: Ryan Roberts 
Acked-by: Alexander Gordeev  # s390
Link: https://lore.kernel.org/r/20250226120656.2400136-2-ryan.roberts@arm.com
Signed-off-by: Will Deacon

MIPS: fix mips_get_syscall_arg() for o32

2025-02-13T11:41:29+00:00

This makes ptrace/get_syscall_info selftest pass on mips o32 and
mips64 o32 by fixing the following two test assertions:

1. get_syscall_info test assertion on mips o32:
  # get_syscall_info.c:218:get_syscall_info:Expected exp_args[5] (3134521044) == info.entry.args[4] (4911432)
  # get_syscall_info.c:219:get_syscall_info:wait #1: entry stop mismatch

2. get_syscall_info test assertion on mips64 o32:
  # get_syscall_info.c:209:get_syscall_info:Expected exp_args[2] (3134324433) == info.entry.args[1] (18446744072548908753)
  # get_syscall_info.c:210:get_syscall_info:wait #1: entry stop mismatch

The first assertion happens due to mips_get_syscall_arg() trying to access
another task's context but failing to do it properly because get_user() it
calls just peeks at the current task's context.  It usually does not crash
because the default user stack always gets assigned the same VMA, but it
is pure luck which mips_get_syscall_arg() wouldn't have if e.g. the stack
was switched (via setcontext(3) or however) or a non-default process's
thread peeked at, and in any case irrelevant data is obtained just as
observed with the test case.

mips_get_syscall_arg() ought to be using access_remote_vm() instead to
retrieve the other task's stack contents, but given that the data has been
already obtained and saved in `struct pt_regs' it would be an overkill.

The first assertion is fixed for mips o32 by using struct pt_regs.args
instead of get_user() to obtain syscall arguments.  This approach works
due to this piece in arch/mips/kernel/scall32-o32.S:

        /*
         * Ok, copy the args from the luser stack to the kernel stack.
         */

        .set    push
        .set    noreorder
        .set    nomacro

    load_a4: user_lw(t5, 16(t0))		# argument #5 from usp
    load_a5: user_lw(t6, 20(t0))		# argument #6 from usp
    load_a6: user_lw(t7, 24(t0))		# argument #7 from usp
    load_a7: user_lw(t8, 28(t0))		# argument #8 from usp
    loads_done:

        sw	t5, PT_ARG4(sp)		# argument #5 to ksp
        sw	t6, PT_ARG5(sp)		# argument #6 to ksp
        sw	t7, PT_ARG6(sp)		# argument #7 to ksp
        sw	t8, PT_ARG7(sp)		# argument #8 to ksp
        .set	pop

        .section __ex_table,"a"
        PTR_WD	load_a4, bad_stack_a4
        PTR_WD	load_a5, bad_stack_a5
        PTR_WD	load_a6, bad_stack_a6
        PTR_WD	load_a7, bad_stack_a7
        .previous

arch/mips/kernel/scall64-o32.S has analogous code for mips64 o32 that
allows fixing the issue by obtaining syscall arguments from struct
pt_regs.regs[4..11] instead of the erroneous use of get_user().

The second assertion is fixed by truncating 64-bit values to 32-bit
syscall arguments.

Fixes: c0ff3c53d4f9 ("MIPS: Enable HAVE_ARCH_TRACEHOOK.")
Signed-off-by: Dmitry V. Levin 
Signed-off-by: Thomas Bogendoerfer

MIPS: Export syscall stack arguments properly for remote use

2025-02-13T11:41:18+00:00

We have several places across the kernel where we want to access another
task's syscall arguments, such as ptrace(2), seccomp(2), etc., by making
a call to syscall_get_arguments().

This works for register arguments right away by accessing the task's
`regs' member of `struct pt_regs', however for stack arguments seen with
32-bit/o32 kernels things are more complicated.  Technically they ought
to be obtained from the user stack with calls to an access_remote_vm(),
but we have an easier way available already.

So as to be able to access syscall stack arguments as regular function
arguments following the MIPS calling convention we copy them over from
the user stack to the kernel stack in arch/mips/kernel/scall32-o32.S, in
handle_sys(), to the current stack frame's outgoing argument space at
the top of the stack, which is where the handler called expects to see
its incoming arguments.  This area is also pointed at by the `pt_regs'
pointer obtained by task_pt_regs().

Make the o32 stack argument space a proper member of `struct pt_regs'
then, by renaming the existing member from `pad0' to `args' and using
generated offsets to access the space.  No functional change though.

With the change in place the o32 kernel stack frame layout at the entry
to a syscall handler invoked by handle_sys() is therefore as follows:

$sp + 68 -> |         ...         | <- pt_regs.regs[9]
            +---------------------+
$sp + 64 -> |         $t0         | <- pt_regs.regs[8]
            +---------------------+
$sp + 60 -> |   $a3/argument #4   | <- pt_regs.regs[7]
            +---------------------+
$sp + 56 -> |   $a2/argument #3   | <- pt_regs.regs[6]
            +---------------------+
$sp + 52 -> |   $a1/argument #2   | <- pt_regs.regs[5]
            +---------------------+
$sp + 48 -> |   $a0/argument #1   | <- pt_regs.regs[4]
            +---------------------+
$sp + 44 -> |         $v1         | <- pt_regs.regs[3]
            +---------------------+
$sp + 40 -> |         $v0         | <- pt_regs.regs[2]
            +---------------------+
$sp + 36 -> |         $at         | <- pt_regs.regs[1]
            +---------------------+
$sp + 32 -> |        $zero        | <- pt_regs.regs[0]
            +---------------------+
$sp + 28 -> |  stack argument #8  | <- pt_regs.args[7]
            +---------------------+
$sp + 24 -> |  stack argument #7  | <- pt_regs.args[6]
            +---------------------+
$sp + 20 -> |  stack argument #6  | <- pt_regs.args[5]
            +---------------------+
$sp + 16 -> |  stack argument #5  | <- pt_regs.args[4]
            +---------------------+
$sp + 12 -> | psABI space for $a3 | <- pt_regs.args[3]
            +---------------------+
$sp +  8 -> | psABI space for $a2 | <- pt_regs.args[2]
            +---------------------+
$sp +  4 -> | psABI space for $a1 | <- pt_regs.args[1]
            +---------------------+
$sp +  0 -> | psABI space for $a0 | <- pt_regs.args[0]
            +---------------------+

holding user data received and with the first 4 frame slots reserved by
the psABI for the compiler to spill the incoming arguments from $a0-$a3
registers (which it sometimes does according to its needs) and the next
4 frame slots designated by the psABI for any stack function arguments
that follow.  This data is also available for other tasks to peek/poke
at as reqired and where permitted.

Signed-off-by: Maciej W. Rozycki 
Signed-off-by: Thomas Bogendoerfer

Merge tag 'mips_6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

2025-01-27T17:00:25+00:00

Pull MIPS updates from Thomas Bogendoerfer:
 "Cleanups and fixes"

* tag 'mips_6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: pci-legacy: Override pci_address_to_pio
  MIPS: Loongson64: env: Use str_on_off() helper in prom_lefi_init_env()
  MIPS: migrate to generic rule for built-in DTBs
  mips: fix shmctl/semctl/msgctl syscall for o32
  mips/math-emu: fix emulation of the prefx instruction
  MIPS: Loongson: Add comments for interface_info
  MIPS: Loongson64: remove ROM Size unit in boardinfo
  MIPS: traps: Use str_enabled_disabled() in parity_protection_init()
  MIPS: ftrace: Declare ftrace_get_parent_ra_addr() as static
  Revert "MIPS: csrc-r4k: Select HAVE_UNSTABLE_SCHED_CLOCK if SMP && 64BIT"
  MIPS: Fix the wrong format specifier
  MIPS: Add a blank line after __HEAD
  MIPS: kernel: Rename read/write_c0_ecc to read/writec0_errctl

asm-generic: pgalloc: provide generic __pgd_{alloc,free}

2025-01-26T04:22:24+00:00

We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free().  Let's finish the work and add a generic PGD-level
alloc helper as well.

Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it.  Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible.  To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.

Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it.  Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.

Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.

Not all PGD allocations can be handled by the generic helpers.  In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.

Link: https://lkml.kernel.org/r/20250103184415.2744423-6-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky 
Acked-by: Dave Hansen 
Acked-by: Qi Zheng 
Cc: Andy Lutomirski 
Cc: Catalin Marinas 
Cc: Ingo Molnar 
Cc: Linus Walleij 
Cc: Matthew Wilcox (Oracle) 
Cc: Mike Rapoport (Microsoft) 
Cc: Peter Zijlstra 
Cc: Ryan Roberts 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Signed-off-by: Andrew Morton