[ Upstream commit e00b0a2ab8 ]
Currently, the parisc kernel does not fully support non-access TLB
fault handling for probe instructions. In the fast path, we set the
target register to zero if it is not a shadowed register. The slow
path is not implemented, so we call do_page_fault. The architecture
indicates that non-access faults should not cause a page fault from
disk.
This change adds to code to provide non-access fault support for
probe instructions. It also modifies the handling of faults on
userspace so that if the address lies in a valid VMA and the access
type matches that for the VMA, the probe target register is set to
one. Otherwise, the target register is set to zero.
This was done to make probe instructions more useful for userspace.
Probe instructions are not very useful if they set the target register
to zero whenever a page is not present in memory. Nominally, the
purpose of the probe instruction is determine whether read or write
access to a given address is allowed.
This fixes a problem in function pointer comparison noticed in the
glibc testsuite (stdio-common/tst-vfprintf-user-type). The same
problem is likely in glibc (_dl_lookup_address).
V2 adds flush and lpa instruction support to handle_nadtlb_fault.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit db19c6f1a2 upstream.
While working on the rewrite to the light-weight syscall and futex code, I
experimented with using a hash index based on the user physical address of
atomic variable. This exposed two problems with the lpa and lpa_user defines.
Because of the copy instruction, the pa argument needs to be an early clobber
argument. This prevents gcc from allocating the va and pa arguments to the same
register.
Secondly, the lpa instruction can cause a page fault so we need to catch
exceptions.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Fixes: 116d753308 ("parisc: Use lpa instruction to load physical addresses in driver code")
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d3a5a68cff upstream.
The address bits used to select the futex spinlock need to match those used in
the LWS code in syscall.S. The mask 0x3f8 only selects 7 bits. It should
select 8 bits.
This change fixes the glibc nptl/tst-cond24 and nptl/tst-cond25 tests.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Fixes: 53a42b6324 ("parisc: Switch to more fine grained lws locks")
Cc: stable@vger.kernel.org # 5.10+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We will not allow unitialized anon mmaps, but we need this define
to prevent build errors, e.g. the debian foot package.
Suggested-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Use READ_ONCE() to check if spinlock is locked.
The other changes are cleanups.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Increase the number of lws locks to 256 entries (instead of 16) and
choose lock entry based on bits 3-11 (instead of 4-7) of the relevant
address. With this change we archieve more fine-grained locking in
futex syscalls and thus reduce the number of possible stalls.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Let the complier treat the pointers volatile to ensure that they get
accessed atomicly.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This change allows the sync barrier instruction to be patched to a nop.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
HPUX has separate NDELAY & NONBLOCK values. In the past we wanted to
be able to run HP-UX binaries natively on parisc Linux which is why
we defined O_NONBLOCK to 000200004 to distinguish NDELAY & NONBLOCK
bits.
But with 2 bits set in this bitmask we often ran into compatibility
issues with other Linux applications which often only test one bit (or
even compare the values).
To avoid such issues in the future, this patch changes O_NONBLOCK to
become 000200000. That way old programs will still be functional, and
for new programs we now have only one bit set.
Update the comment about SOCK_NONBLOCK too.
Signed-off-by: Helge Deller <deller@gmx.de>
Those flags are nowhere used in the Linux kernel and were added when we
still wanted to support HP-UX in a compat mode. Since we never will
support HP-UX, drop those flags.
Signed-off-by: Helge Deller <deller@gmx.de>
Pull compat quotactl cleanups from Al Viro:
"More Christoph's compat cleanups: quotactl(2)"
* 'work.quota-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
quota: simplify the quotactl compat handling
compat: add a compat_need_64bit_alignment_fixup() helper
compat: lift compat_s64 and compat_u64 to <asm-generic/compat.h>
lift the compat_s64 and compat_u64 definitions into common code using the
COMPAT_FOR_U64_ALIGNMENT symbol for the x86 special case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All callers of these primitives will
* discard anything we might've copied in case of error
* ignore the csum value in case of error
* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.
That suggest the following calling conventions:
* don't pass err_ptr - just return 0 on error.
* don't bother with zeroing destination, etc. in case of error
* don't pass the initial sum - just use 0xffffffff.
This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff. Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.
A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them. Not sure if it's worth
a separate commit...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
quite a few architectures have the same csum_partial_copy_nocheck() -
simply memcpy() the data and then return the csum of the copy.
hexagon, parisc, ia64, s390, um: explicitly spelled out that way.
arc, arm64, csky, h8300, m68k/nommu, microblaze, mips/GENERIC_CSUM, nds32,
nios2, openrisc, riscv, unicore32: end up picking the same thing spelled
out in lib/checksum.h (with varying amounts of perversions along the way).
everybody else (alpha, arm, c6x, m68k/mmu, mips/!GENERIC_CSUM, powerpc,
sh, sparc, x86, xtensa) have non-generic variants. For all except c6x
the declaration is in their asm/checksum.h. c6x uses the wrapper
from asm-generic/checksum.h that would normally lead to the lib/checksum.h
instance, but in case of c6x we end up using an asm function from arch/c6x
instead.
Screw that mess - have architectures with private instances define
_HAVE_ARCH_CSUM_AND_COPY in their asm/checksum.h and have the default
one right in net/checksum.h conditional on _HAVE_ARCH_CSUM_AND_COPY
*not* defined.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit 1355c31eeb ("asm-generic: pgalloc: provide generic pmd_alloc_one()
and pmd_free_one()") converted parisc to use generic version of
pmd_alloc_one() but it missed the fact that parisc uses order-1 pages for
PMD.
Restore the original version of pmd_alloc_one() for parisc, just use
GFP_PGTABLE_KERNEL that implies __GFP_ZERO instead of GFP_KERNEL and
memset.
Fixes: 1355c31eeb ("asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()")
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lkml.kernel.org/r/9f2b5ebd-e4a4-0fa1-6cd3-4b9f6892d1ad@linux.ee
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull more parisc updates from Helge Deller:
- Oscar Carter contributed a patch which fixes parisc's usage of
dereference_function_descriptor() and thus will allow using the
-Wcast-function-type compiler option in the top-level Makefile
- Sven Schnelle fixed a bug in the SBA code to prevent crashes during
kexec
- John David Anglin provided implementations for __smp_store_release()
and __smp_load_acquire barriers() which avoids using the sync
assembler instruction and thus speeds up barrier paths
- Some whitespace cleanups in parisc's atomic.h header file
* 'parisc-5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Implement __smp_store_release and __smp_load_acquire barriers
parisc: mask out enable and reserved bits from sba imask
parisc: Whitespace cleanups in atomic.h
parisc/kernel/ftrace: Remove function callback casts
sections.h: dereference_function_descriptor() returns void pointer
This patch implements the __smp_store_release and __smp_load_acquire barriers
using ordered stores and loads. This avoids the sync instruction present in
the generic implementation.
Cc: <stable@vger.kernel.org> # 4.14+
Signed-off-by: Dave Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
