linux-stable.git/arch/nds32/include/asm, branch linux-5.4.y

arch, mm: remove stale mentions of DISCONIGMEM

2024-02-23T07:25:13+00:00

[ Upstream commit d3c251ab95b69f3dc189c4657baeac1b4c050789 ]

There are several places that mention DISCONIGMEM in comments or have
stale code guarded by CONFIG_DISCONTIGMEM.

Remove the dead code and update the comments.

Link: https://lkml.kernel.org/r/20210608091316.3622-7-rppt@kernel.org
Signed-off-by: Mike Rapoport 
Acked-by: Arnd Bergmann 
Reviewed-by: David Hildenbrand 
Cc: Geert Uytterhoeven 
Cc: Ivan Kokshaysky 
Cc: Jonathan Corbet 
Cc: Matt Turner 
Cc: Richard Henderson 
Cc: Vineet Gupta 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Stable-dep-of: e1a9ae457369 ("mips: Fix max_mapnr being uninitialized on early stages")
Signed-off-by: Sasha Levin

nds32: fix access_ok() checks in get/put_user

2022-03-28T06:46:48+00:00

commit 8926d88ced46700bf6117ceaf391480b943ea9f4 upstream.

The get_user()/put_user() functions are meant to check for
access_ok(), while the __get_user()/__put_user() functions
don't.

This broke in 4.19 for nds32, when it gained an extraneous
check in __get_user(), but lost the check it needs in
__put_user().

Fixes: 487913ab18c2 ("nds32: Extract the checking and getting pointer to a macro")
Cc: stable@vger.kernel.org @ v4.19+
Reviewed-by: Christoph Hellwig 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

asm-generic/nds32: don't redefine cacheflush primitives

2020-01-17T18:48:43+00:00

commit 4f0bd808134d73184054ad09173821c84f31dd5d upstream.

The commit c296d4dc13ae ("asm-generic: fix a compilation warning") changed
asm-generic/cachflush.h to use static inlines instead of macros and as a
result the nds32 build with CONFIG_CPU_CACHE_ALIASING=n fails:

  CC      init/main.o
In file included from arch/nds32/include/asm/cacheflush.h:43,
                 from include/linux/highmem.h:12,
                 from include/linux/pagemap.h:11,
                 from include/linux/blkdev.h:16,
                 from include/linux/blk-cgroup.h:23,
                 from include/linux/writeback.h:14,
                 from init/main.c:44:
include/asm-generic/cacheflush.h:50:20: error: static declaration of 'flush_icache_range' follows non-static declaration
 static inline void flush_icache_range(unsigned long start, unsigned long end)
                    ^~~~~~~~~~~~~~~~~~
In file included from include/linux/highmem.h:12,
                 from include/linux/pagemap.h:11,
                 from include/linux/blkdev.h:16,
                 from include/linux/blk-cgroup.h:23,
                 from include/linux/writeback.h:14,
                 from init/main.c:44:
arch/nds32/include/asm/cacheflush.h:11:6: note: previous declaration of 'flush_icache_range' was here
 void flush_icache_range(unsigned long start, unsigned long end);
      ^~~~~~~~~~~~~~~~~~

Surround the inline functions in asm-generic/cacheflush.h by ifdef's so
that architectures could override them and add the required overrides to
nds32.

Fixes: c296d4dc13ae ("asm-generic: fix a compilation warning")
Link: https://lore.kernel.org/lkml/201912212139.yptX8CsV%25lkp@intel.com/
Reported-by: kbuild test robot 
Signed-off-by: Mike Rapoport 
Reviewed-by: Greentime Hu 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

mm: consolidate pgtable_cache_init() and pgd_cache_init()

2019-09-24T22:54:09+00:00

Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.

Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init().  Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.

Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().

Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport 
Acked-by: Will Deacon 		[arm64]
Acked-by: Thomas Gleixner 	[x86]
Cc: Catalin Marinas 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Matthew Wilcox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: remove quicklist page table caches

2019-09-24T22:54:09+00:00

Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.

[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com

This patch (of 3):

Remove page table allocator "quicklists".  These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.

The numbers in the initial commit look interesting but probably don't
apply anymore.  If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.

Also it might be better to instead make more general improvements to page
allocator if this is still so slow.

Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin 
Signed-off-by: Mike Rapoport 
Cc: Tony Luck 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nds32: fix asm/syscall.h

2019-07-17T02:23:24+00:00

PTRACE_GET_SYSCALL_INFO is a generic ptrace API that lets ptracer obtain
details of the syscall the tracee is blocked in.

There are two reasons for a special syscall-related ptrace request.

Firstly, with the current ptrace API there are cases when ptracer cannot
retrieve necessary information about syscalls.  Some examples include:

 * The notorious int-0x80-from-64-bit-task issue. See [1] for details.
   In short, if a 64-bit task performs a syscall through int 0x80, its
   tracer has no reliable means to find out that the syscall was, in
   fact, a compat syscall, and misidentifies it.

 * Syscall-enter-stop and syscall-exit-stop look the same for the
   tracer. Common practice is to keep track of the sequence of
   ptrace-stops in order not to mix the two syscall-stops up. But it is
   not as simple as it looks; for example, strace had a (just recently
   fixed) long-standing bug where attaching strace to a tracee that is
   performing the execve system call led to the tracer identifying the
   following syscall-exit-stop as syscall-enter-stop, which messed up
   all the state tracking.

 * Since the introduction of commit 84d77d3f06e7 ("ptrace: Don't allow
   accessing an undumpable mm"), both PTRACE_PEEKDATA and
   process_vm_readv become unavailable when the process dumpable flag is
   cleared. On such architectures as ia64 this results in all syscall
   arguments being unavailable for the tracer.

Secondly, ptracers also have to support a lot of arch-specific code for
obtaining information about the tracee.  For some architectures, this
requires a ptrace(PTRACE_PEEKUSER, ...) invocation for every syscall
argument and return value.

PTRACE_GET_SYSCALL_INFO returns the following structure:

struct ptrace_syscall_info {
	__u8 op;	/* PTRACE_SYSCALL_INFO_* */
	__u32 arch __attribute__((__aligned__(sizeof(__u32))));
	__u64 instruction_pointer;
	__u64 stack_pointer;
	union {
		struct {
			__u64 nr;
			__u64 args[6];
		} entry;
		struct {
			__s64 rval;
			__u8 is_error;
		} exit;
		struct {
			__u64 nr;
			__u64 args[6];
			__u32 ret_data;
		} seccomp;
	};
};

The structure was chosen according to [2], except for the following
changes:

 * seccomp substructure was added as a superset of entry substructure

 * the type of nr field was changed from int to __u64 because syscall
   numbers are, as a practical matter, 64 bits

 * stack_pointer field was added along with instruction_pointer field
   since it is readily available and can save the tracer from extra
   PTRACE_GETREGS/PTRACE_GETREGSET calls

 * arch is always initialized to aid with tracing system calls such as
   execve()

 * instruction_pointer and stack_pointer are always initialized so they
   could be easily obtained for non-syscall stops

 * a boolean is_error field was added along with rval field, this way
   the tracer can more reliably distinguish a return value from an error
   value

strace has been ported to PTRACE_GET_SYSCALL_INFO.  Starting with
release 4.26, strace uses PTRACE_GET_SYSCALL_INFO API as the preferred
mechanism of obtaining syscall information.

[1] https://lore.kernel.org/lkml/CA+55aFzcSVmdDj9Lh_gdbz1OzHyEm6ZrGPBDAJnywm2LF_eVyg@mail.gmail.com/
[2] https://lore.kernel.org/lkml/CAObL_7GM0n80N7J_DFw_eQyfLyzq+sf4y2AvsCCV88Tb3AwEHA@mail.gmail.com/

This patch (of 7):

All syscall_get_*() and syscall_set_*() functions must be defined as
static inline as on all other architectures, otherwise asm/syscall.h
cannot be included in more than one compilation unit.

This bug has to be fixed in order to extend the generic
ptrace API with PTRACE_GET_SYSCALL_INFO request.

Link: http://lkml.kernel.org/r/20190510152749.GA28558@altlinux.org
Fixes: 1932fbe36e02 ("nds32: System calls handling")
Signed-off-by: Dmitry V. Levin 
Reported-by: kbuild test robot 
Acked-by: Greentime Hu 
Cc: Vincent Chen 
Cc: Elvira Khabirova 
Cc: Eugene Syromyatnikov 
Cc: Oleg Nesterov 
Cc: Andy Lutomirski 
Cc: Benjamin Herrenschmidt 
Cc: Helge Deller 	[parisc]
Cc: James E.J. Bottomley 
Cc: James Hogan 
Cc: Kees Cook 
Cc: Michael Ellerman 
Cc: Paul Burton 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Cc: Richard Kuo 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nds32: switch to generic version of pte allocation

2019-07-12T18:05:45+00:00

The nds32 implementation of pte_alloc_one_kernel() differs from the
generic in the use of __GFP_RETRY_MAYFAIL flag, which is removed after the
conversion.

The nds32 version of pte_alloc_one() missed the call to
pgtable_page_ctor() and also used __GFP_RETRY_MAYFAIL.  Switching it to
use generic __pte_alloc_one() for the PTE page allocation ensures that
page table constructor is run and the user page tables are allocated with
__GFP_ACCOUNT.

The conversion to the generic version of pte_free_kernel() removes the
NULL check for pte.

The pte_free() version on nds32 is identical to the generic one and can be
simply dropped.

Link: http://lkml.kernel.org/r/1557296232-15361-10-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport 
Cc: Albert Ou 
Cc: Anshuman Khandual 
Cc: Anton Ivanov 
Cc: Arnd Bergmann 
Cc: Catalin Marinas 
Cc: Geert Uytterhoeven 
Cc: Greentime Hu 
Cc: Guan Xuetao 
Cc: Guo Ren 
Cc: Guo Ren 
Cc: Helge Deller 
Cc: Ley Foon Tan 
Cc: Matthew Wilcox 
Cc: Matt Turner 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Palmer Dabbelt 
Cc: Paul Burton 
Cc: Ralf Baechle 
Cc: Richard Kuo 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Sam Creasey 
Cc: Vincent Chen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'nds32-for-linux-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux

2019-06-03T17:23:41+00:00

Pull nds32 fixes from Greentime Hu:

 - fix warning for math-emu

 - fix nds32 fpu exception handling

 - fix nds32 fpu emulation implementation

* tag 'nds32-for-linux-5.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/greentime/linux:
  nds32: add new emulations for floating point instruction
  nds32: Avoid IEX status being incorrectly modified
  math-emu: Use statement expressions to fix Wshift-count-overflow warning

nds32: add new emulations for floating point instruction

2019-05-31T07:23:26+00:00

The existing floating point emulations is only available for floating
instruction that possibly issue denormalized input and underflow
exceptions. These existing FPU emulations are not sufficient when IEx
Trap is enabled because some floating point instructions only issue inexact
exception. This patch adds the emulations of such floating point
instructions.

Signed-off-by: Vincent Chen 
Acked-by: Greentime Hu 
Signed-off-by: Greentime Hu

nds32: Avoid IEX status being incorrectly modified

2019-05-31T07:23:26+00:00

In order for kernel to capture each denormalized output, the UDF
trapping enable bit is always raised in $fpcsr. Because underflow case will
issue not an underflow exception but also an inexact exception, it causes
that the IEX, IEX cumulative exception, flag in $fpcsr to be raised in each
denormalized output handling. To make the emulation transparent to the
user, the emulator needs to clear the IEX flag in $fpcsr if the result is a
denormalized number. However, if the IEX flag has been raised before this
floating point emulation, this cleanup may be incorrect. To avoid the IEX
flags in $fpcsr be raised in each denormalized output handling, the IEX
trap shall be always enabled.

Signed-off-by: Vincent Chen 
Acked-by: Greentime Hu 
Signed-off-by: Greentime Hu