Commit Graph

1189 Commits

Author SHA1 Message Date
Max Filippov
aea59964f5 xtensa: fix return_address
commit ada770b1e7 upstream.

return_address returns the address that is one level higher in the call
stack than requested in its argument, because level 0 corresponds to its
caller's return address. Use requested level as the number of stack
frames to skip.

This fixes the address reported by might_sleep and friends.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-17 08:36:47 +02:00
Max Filippov
7d1ef64eca xtensa: SMP: limit number of possible CPUs by NR_CPUS
[ Upstream commit 25384ce5f9 ]

This fixes the following warning at boot when the kernel is booted on a
board with more CPU cores than was configured in NR_CPUS:

  smp_init_cpus: Core Count = 8
  smp_init_cpus: Core Id = 0
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 #124
  Call Trace:
    __warn$part$3+0x6a/0x7c
    warn_slowpath_null+0x35/0x3c
    smp_init_cpus+0x54/0x74
    setup_arch+0x1c0/0x1d0
    start_kernel+0x44/0x310
    _startup+0x107/0x107

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:04:56 -07:00
Max Filippov
11a4dc8909 xtensa: SMP: mark each possible CPU as present
[ Upstream commit 8b1c42cdd7 ]

Otherwise it is impossible to enable CPUs after booting with 'maxcpus'
parameter.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:04:56 -07:00
Max Filippov
db325a389c xtensa: smp_lx200_defconfig: fix vectors clash
[ Upstream commit 306b38305c ]

Secondary CPU reset vector overlaps part of the double exception handler
code, resulting in weird crashes and hangups when running user code.
Move exception vectors one page up so that they don't clash with the
secondary CPU reset vector.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:04:56 -07:00
Max Filippov
e2f3fd4d5b xtensa: SMP: fix secondary CPU initialization
[ Upstream commit 32a7726c4f ]

- add missing memory barriers to the secondary CPU synchronization spin
  loops; add comment to the matching memory barrier in the boot_secondary
  and __cpu_die functions;
- use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount
  instead of reading/writing them directly;
- re-initialize cpu_running every time before starting secondary CPU to
  flush possible previous CPU startup results.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:04:56 -07:00
Max Filippov
aa9b819bee xtensa: SMP: fix ccount_timer_shutdown
[ Upstream commit 4fe8713b87 ]

ccount_timer_shutdown is called from the atomic context in the
secondary_start_kernel, resulting in the following BUG:

BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1
Preemption disabled at:
  secondary_start_kernel+0xa1/0x130
Call Trace:
  ___might_sleep+0xe7/0xfc
  __might_sleep+0x41/0x44
  synchronize_irq+0x24/0x64
  disable_irq+0x11/0x14
  ccount_timer_shutdown+0x12/0x20
  clockevents_switch_state+0x82/0xb4
  clockevents_exchange_device+0x54/0x60
  tick_check_new_device+0x46/0x70
  clockevents_register_device+0x8c/0xc8
  clockevents_config_and_register+0x1d/0x2c
  local_timer_setup+0x75/0x7c
  secondary_start_kernel+0xb4/0x130
  should_never_return+0x32/0x35

Use disable_irq_nosync instead of disable_irq to avoid it.
This is safe because the ccount timer IRQ is per-CPU, and once IRQ is
masked the ISR will not be called.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:04:55 -07:00
Max Filippov
f403887502 xtensa: fix coprocessor context offset definitions
commit 03bc996af0 upstream.

Coprocessor context offsets are used by the assembly code that moves
coprocessor context between the individual fields of the
thread_info::xtregs_cp structure and coprocessor registers.
This fixes coprocessor context clobbering on flushing and reloading
during normal user code execution and user process debugging in the
presence of more than one coprocessor in the core configuration.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 19:42:39 +01:00
Max Filippov
c26e3c6c2d xtensa: enable coprocessors that are being flushed
commit 2958b66694 upstream.

coprocessor_flush_all may be called from a context of a thread that is
different from the thread being flushed. In that case contents of the
cpenable special register may not match ti->cpenable of the target
thread, resulting in unhandled coprocessor exception in the kernel
context.
Set cpenable special register to the ti->cpenable of the target register
for the duration of the flush and restore it afterwards.
This fixes the following crash caused by coprocessor register inspection
in native gdb:

  (gdb) p/x $w0
  Illegal instruction in kernel: sig: 9 [#1] PREEMPT
  Call Trace:
    ___might_sleep+0x184/0x1a4
    __might_sleep+0x41/0xac
    exit_signals+0x14/0x218
    do_exit+0xc9/0x8b8
    die+0x99/0xa0
    do_illegal_instruction+0x18/0x6c
    common_exception+0x77/0x77
    coprocessor_flush+0x16/0x3c
    arch_ptrace+0x46c/0x674
    sys_ptrace+0x2ce/0x3b4
    system_call+0x54/0x80
    common_exception+0x77/0x77
  note: gdb[100] exited with preempt_count 1
  Killed

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-05 19:42:39 +01:00
Max Filippov
0dac028156 xtensa: fix boot parameters address translation
commit 40dc948f23 upstream.

The bootloader may pass physical address of the boot parameters structure
to the MMUv3 kernel in the register a2. Code in the _SetupMMU block in
the arch/xtensa/kernel/head.S is supposed to map that physical address to
the virtual address in the configured virtual memory layout.

This code haven't been updated when additional 256+256 and 512+512
memory layouts were introduced and it may produce wrong addresses when
used with these layouts.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:25:59 +01:00
Max Filippov
a10aa331aa xtensa: make sure bFLT stack is 16 byte aligned
commit 0773495b1f upstream.

Xtensa ABI requires stack alignment to be at least 16. In noMMU
configuration ARCH_SLAB_MINALIGN is used to align stack. Make it at
least 16.

This fixes the following runtime error in noMMU configuration, caused by
interaction between insufficiently aligned stack and alloca function,
that results in corruption of on-stack variable in the libc function
glob:

 Caught unhandled exception in 'sh' (pid = 47, pc = 0x02d05d65)
  - should not happen
  EXCCAUSE is 15

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:25:59 +01:00
Max Filippov
c9226141c2 xtensa: add NOTES section to the linker script
commit 4119ba211b upstream.

This section collects all source .note.* sections together in the
vmlinux image. Without it .note.Linux section may be placed at address
0, while the rest of the kernel is at its normal address, resulting in a
huge vmlinux.bin image that may not be linked into the xtensa Image.elf.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:25:59 +01:00
Max Filippov
7f2163b56e xtensa: increase ranges in ___invalidate_{i,d}cache_all
commit fec3259c9f upstream.

Cache invalidation macros use cache line size to iterate over
invalidated cache lines, assuming that all cache ways are invalidated by
single instruction, but xtensa ISA recommends to not assume that for
future compatibility:
  In some implementations all ways at index Addry-1..z are invalidated
  regardless of the specified way, but for future compatibility this
  behavior should not be assumed.

Iterate over all cache ways in ___invalidate_icache_all and
___invalidate_dcache_all.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09 20:01:23 +02:00
Max Filippov
e996a24db2 xtensa: limit offsets in __loop_cache_{all,page}
commit be75de2525 upstream.

When building kernel for xtensa cores with big cache lines (e.g. 128
bytes or more) __loop_cache_all and __loop_cache_page may generate
assembly instructions with immediate fields that are too big. This
results in the following build errors:

  arch/xtensa/mm/misc.S: Assembler messages:
  arch/xtensa/mm/misc.S:464: Error: operand 2 of 'diwbi' has invalid value '256'
  arch/xtensa/mm/misc.S:464: Error: operand 2 of 'diwbi' has invalid value '384'
  arch/xtensa/kernel/head.S: Assembler messages:
  arch/xtensa/kernel/head.S:172: Error: operand 2 of 'diu' has invalid value '256'
  arch/xtensa/kernel/head.S:172: Error: operand 2 of 'diu' has invalid value '384'
  arch/xtensa/kernel/head.S:176: Error: operand 2 of 'iiu' has invalid value '256'
  arch/xtensa/kernel/head.S:176: Error: operand 2 of 'iiu' has invalid value '384'
  arch/xtensa/kernel/head.S:255: Error: operand 2 of 'diwb' has invalid value '256'
  arch/xtensa/kernel/head.S:255: Error: operand 2 of 'diwb' has invalid value '384'

Add parameter max_immed to these macros and use it to limit values of
immediate operands. Extract common code of these macros into the new
macro __loop_cache_unroll.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-09 20:01:23 +02:00
Eric W. Biederman
c82ccd7122 signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
commit 7de712ccc0 upstream.

While working on changing this code to use force_sig_fault I
discovered that do_unaliged_user is sets si_signo to SIGBUS and passes
SIGSEGV to force_sig_info.  Which is just b0rked.

The code is reporting a SIGBUS error so replace the SIGSEGV with SIGBUS.

Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Cc: stable@vger.kernel.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Fixes: 5a0015d626 ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 3")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:23:06 +02:00
Jiri Slaby
81da9f87ad futex: Remove duplicated code and fix undefined behaviour
commit 30d6e0a419 upstream.

There is code duplicated over all architecture's headers for
futex_atomic_op_inuser. Namely op decoding, access_ok check for uaddr,
and comparison of the result.

Remove this duplication and leave up to the arches only the needed
assembly which is now in arch_futex_atomic_op_inuser.

This effectively distributes the Will Deacon's arm64 fix for undefined
behaviour reported by UBSAN to all architectures. The fix was done in
commit 5f16a046f8 (arm64: futex: Fix undefined behaviour with
FUTEX_OP_OPARG_SHIFT usage). Look there for an example dump.

And as suggested by Thomas, check for negative oparg too, because it was
also reported to cause undefined behaviour report.

Note that s390 removed access_ok check in d12a29703 ("s390/uaccess:
remove pointless access_ok() checks") as access_ok there returns true.
We introduce it back to the helper for the sake of simplicity (it gets
optimized away anyway).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390]
Acked-by: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com> [core/arm64]
Cc: linux-mips@linux-mips.org
Cc: Rich Felker <dalias@libc.org>
Cc: linux-ia64@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: peterz@infradead.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sparclinux@vger.kernel.org
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux-s390@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-hexagon@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-xtensa@linux-xtensa.org
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: openrisc@lists.librecores.org
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Stafford Horne <shorne@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Henderson <rth@twiddle.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-parisc@vger.kernel.org
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-alpha@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20170824073105.3901-1-jslaby@suse.cz
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-19 10:27:00 +02:00
Max Filippov
a5ecf56cb2 xtensa: fix high memory/reserved memory collision
commit 6ac5a11dc6 upstream.

Xtensa memory initialization code frees high memory pages without
checking whether they are in the reserved memory regions or not. That
results in invalid value of totalram_pages and duplicate page usage by
CMA and highmem. It produces a bunch of BUGs at startup looking like
this:

BUG: Bad page state in process swapper  pfn:70800
page:be60c000 count:0 mapcount:-127 mapping:  (null) index:0x1
flags: 0x80000000()
raw: 80000000 00000000 00000001 ffffff80 00000000 be60c014 be60c014 0000000a
page dumped because: nonzero mapcount
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Tainted: G    B            4.16.0-rc1-00015-g7928b2cbe55b-dirty #23
Stack:
 bd839d33 00000000 00000018 ba97b64c a106578c bd839d70 be60c000 00000000
 a1378054 bd86a000 00000003 ba97b64c a1066166 bd839da0 be60c000 ffe00000
 a1066b58 bd839dc0 be504000 00000000 000002f4 bd838000 00000000 0000001e
Call Trace:
 [<a1065734>] bad_page+0xac/0xd0
 [<a106578c>] free_pages_check_bad+0x34/0x4c
 [<a1066166>] __free_pages_ok+0xae/0x14c
 [<a1066b58>] __free_pages+0x30/0x64
 [<a1365de5>] init_cma_reserved_pageblock+0x35/0x44
 [<a13682dc>] cma_init_reserved_areas+0xf4/0x148
 [<a10034b8>] do_one_initcall+0x80/0xf8
 [<a1361c16>] kernel_init_freeable+0xda/0x13c
 [<a125b59d>] kernel_init+0x9/0xd0
 [<a1004304>] ret_from_kernel_thread+0xc/0x18

Only free high memory pages that are not reserved.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 10:18:30 +01:00
Max Filippov
2d4e295284 xtensa: fix futex_atomic_cmpxchg_inatomic
commit ca47480921 upstream.

Return 0 if the operation was successful, not the userspace memory
value. Check that userspace value equals passed oldval, not itself.
Don't update *uval if the value wasn't read from userspace memory.

This fixes process hang due to infinite loop in futex_lock_pi.
It also fixes a bunch of glibc tests nptl/tst-mutexpi*.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-17 13:21:19 +01:00
Max Filippov
a311810903 xtensa: don't limit csum_partial export by CONFIG_NET
commit 7f81e55c73 upstream.

csum_partial and csum_partial_copy_generic are defined unconditionally
and are available even when CONFIG_NET is disabled. They are used not
only by the network drivers, but also by scsi and media.
Don't limit these functions export by CONFIG_NET.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 13:43:16 -07:00
Max Filippov
a3ab0f069f xtensa: mm/cache: add missing EXPORT_SYMBOLs
commit bc652eb6a0 upstream.

Functions clear_user_highpage, copy_user_highpage, flush_dcache_page,
local_flush_cache_range and local_flush_cache_page may be used from
modules. Export them.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 13:43:15 -07:00
Max Filippov
03973c57e1 xtensa: fix cache aliasing handling code for WT cache
commit 6d0f581d17 upstream.

Currently building kernel for xtensa core with aliasing WT cache fails
with the following messages:

  mm/memory.c:2152: undefined reference to `flush_dcache_page'
  mm/memory.c:2332: undefined reference to `local_flush_cache_page'
  mm/memory.c:1919: undefined reference to `local_flush_cache_range'
  mm/memory.c:4179: undefined reference to `copy_to_user_page'
  mm/memory.c:4183: undefined reference to `copy_from_user_page'

This happens because implementation of these functions is only compiled
when data cache is WB, which looks wrong: even when data cache doesn't
need flushing it still needs invalidation. The functions like
__flush_[invalidate_]dcache_* are correctly defined for both WB and WT
caches (and even if they weren't that'd still be ok, just slower).

Fix this by providing the same implementation of the above functions for
both WB and WT cache.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 13:43:15 -07:00
Hugh Dickins
cfc0eb4038 mm: larger stack guard gap, between vmas
commit 1be7107fbe upstream.

Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.

This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.

Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.

One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications.  For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).

Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.

Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.

Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[wt: backport to 4.11: adjust context]
[wt: backport to 4.9: adjust context ; kernel doc was not in admin-guide]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-24 07:11:18 +02:00
Max Filippov
a2f6827682 xtensa: don't use linux IRQ #0
commit e5c86679d5 upstream.

Linux IRQ #0 is reserved for error reporting and may not be used.
Increase NR_IRQS for one additional slot and increase
irq_domain_add_legacy parameter first_irq value to 1, so that linux
IRQ #0 is not associated with hardware IRQ #0 in legacy IRQ domains.
Introduce macro XTENSA_PIC_LINUX_IRQ for static translation of xtensa
PIC hardware IRQ # to linux IRQ #. Use this macro in XTFPGA platform
data definitions.

This fixes inability to use hardware IRQ #0 in configurations that don't
use device tree and allows for non-identity mapping between linux IRQ #
and hardware IRQ #.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17 06:41:58 +02:00
Max Filippov
6a776f6ae3 xtensa: make __pa work with uncached KSEG addresses
commit 2b83878dd7 upstream.

When __pa is applied to virtual address in uncached KSEG region the
result is incorrect. Fix it by checking if the original address is in
the uncached KSEG and adjusting the result. It looks better than masking
off bits because pfn_valid would correctly work with new __pa results
and it may be made working in noMMU case, once we get definition for
uncached memory view.

This is required for the dma_common_mmap and DMA debug code to work
correctly: they both indirectly use __pa with coherent DMA addresses.
In case of DMA debug the visible effect is false reports that an address
mapped for DMA is accessed by CPU.

Tested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:14 +02:00
Max Filippov
a7b9c9ddb6 xtensa: move parse_tag_fdt out of #ifdef CONFIG_BLK_DEV_INITRD
commit 4ab18701c6 upstream.

FDT tag parsing is not related to whether BLK_DEV_INITRD is configured
or not, move it out of the corresponding #ifdef/#endif block.
This fixes passing external FDT to the kernel configured w/o
BLK_DEV_INITRD support.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-15 10:02:47 +08:00
Max Filippov
dfd713307a xtensa: fix noMMU build on cores with MMU
commit 4b3e6f2ef3 upstream.

Commit bf15f86b34 ("xtensa: initialize MMU before jumping to reset
vector") calls MMU management functions even when CONFIG_MMU is not
selected. That breaks noMMU build on cores with MMU.

Don't manage MMU when CONFIG_MMU is not selected.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-09 08:08:25 +01:00
Max Filippov
709fb1f961 xtensa: wire up new pkey_{mprotect,alloc,free} syscalls
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-11-14 12:31:49 -08:00
Max Filippov
d4eccafcaf xtensa: clean up printk usage for boot/crash logging
Convert printk(KERN_* to pr_* and printk's without level to pr_cont.
This fixes torn register dumps, stack dumps, stack traces and timestamps
in the middle of 'Calibrating CPU frequency' message.
Also drop unused show_code and drop false comment about show_stack.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-11-06 23:31:46 -08:00
Linus Torvalds
4cdf8dbe2d Merge branch 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess.h prepwork from Al Viro:
 "Preparations to tree-wide switch to use of linux/uaccess.h (which,
  obviously, will allow to start unifying stuff for real). The last step
  there, ie

    PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
    sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
            `git grep -l "$PATT"|grep -v ^include/linux/uaccess.h`

  is not taken here - I would prefer to do it once just before or just
  after -rc1.  However, everything should be ready for it"

* 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  remove a stray reference to asm/uaccess.h in docs
  sparc64: separate extable_64.h, switch elf_64.h to it
  score: separate extable.h, switch module.h to it
  mips: separate extable.h, switch module.h to it
  x86: separate extable.h, switch sections.h to it
  remove stray include of asm/uaccess.h from cacheflush.h
  mn10300: remove a bogus processor.h->uaccess.h include
  xtensa: split uaccess.h into C and asm sides
  bonding: quit messing with IOCTL
  kill __kernel_ds_p off
  mn10300: finish verify_area() off
  frv: move HAVE_ARCH_UNMAPPED_AREA to pgtable.h
  exceptions: detritus removal
2016-10-11 23:38:39 -07:00
Linus Torvalds
93c26d7dc0 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull protection keys syscall interface from Thomas Gleixner:
 "This is the final step of Protection Keys support which adds the
  syscalls so user space can actually allocate keys and protect memory
  areas with them. Details and usage examples can be found in the
  documentation.

  The mm side of this has been acked by Mel"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/pkeys: Update documentation
  x86/mm/pkeys: Do not skip PKRU register if debug registers are not used
  x86/pkeys: Fix pkeys build breakage for some non-x86 arches
  x86/pkeys: Add self-tests
  x86/pkeys: Allow configuration of init_pkru
  x86/pkeys: Default to a restrictive init PKRU
  pkeys: Add details of system call use to Documentation/
  generic syscalls: Wire up memory protection keys syscalls
  x86: Wire up protection keys system calls
  x86/pkeys: Allocation/free syscalls
  x86/pkeys: Make mprotect_key() mask off additional vm_flags
  mm: Implement new pkey_mprotect() system call
  x86/pkeys: Add fault handling for PF_PK page fault bit
2016-10-10 11:01:51 -07:00
Chris Metcalf
6727ad9e20 nmi_backtrace: generate one-line reports for idle cpus
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative.  Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".

We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.

This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.

Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org> [arm]
Tested-by: Petr Mladek <pmladek@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:30 -07:00
Linus Torvalds
d8ea757b25 Merge tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa
Pull Xtensa updates from Max Filippov:
 "Updates for the xtensa architecture.  It is a combined set of patches
  for 4.8 that never got to the mainline and new patches for 4.9.

   - add new kernel memory layouts for MMUv3 cores: with 256MB and 512MB
     KSEG size, starting at physical address other than 0

   - make kernel load address configurable

   - clean up kernel memory layout macros

   - drop sysmem early allocator and switch to memblock

   - enable kmemleak and memory reservation from the device tree

   - wire up new syscalls: userfaultfd, membarrier, mlock2,
     copy_file_range, preadv2 and pwritev2

   - add new platform: Cadence Configurable System Platform (CSP) and
     new core variant for it: xt_lnx

   - rearrange CCOUNT calibration code, make most of it generic

   - improve machine reset code (XTFPGA now reboots reliably with MMUv3
     cores)

   - provide default memmap command line option for configurations
     without device tree support

   - ISS fixes: simdisk is now capable of using highmem pages, panic
     correctly terminates simulator"

* tag 'xtensa-20161005' of git://github.com/jcmvbkbc/linux-xtensa: (24 commits)
  xtensa: disable MMU initialization option on MMUv2 cores
  xtensa: add default memmap and mmio32native options to defconfigs
  xtensa: add default memmap option to common_defconfig
  xtensa: add default memmap option to iss_defconfig
  xtensa: ISS: allow simdisk to use high memory buffers
  xtensa: ISS: define simc_exit and use it instead of inline asm
  xtensa: xtfpga: group platform_* functions together
  xtensa: rearrange CCOUNT calibration
  xtensa: xtfpga: use clock provider, don't update DT
  xtensa: Tweak xuartps UART driver Rx watermark for Cadence CSP config.
  xtensa: initialize MMU before jumping to reset vector
  xtensa: fix icountlevel setting in cpu_reset
  xtensa: extract common CPU reset code into separate function
  xtensa: Added Cadence CSP kernel configuration for Xtensa
  xtensa: fix default kernel load address
  xtensa: wire up new syscalls
  xtensa: support reserved-memory DT node
  xtensa: drop sysmem and switch to memblock
  xtensa: minimize use of PLATFORM_DEFAULT_MEM_{ADDR,SIZE}
  xtensa: cleanup MMU setup and kernel layout macros
  ...
2016-10-05 17:44:48 -07:00
Max Filippov
a4c6be5ad1 xtensa: disable MMU initialization option on MMUv2 cores
MMU initialization option is currently ignored on MMUv2 cores, but it is
used in Kconfig to select kernel load and start addresses. This choice
is not available for MMUv2 cores as they have hardwired TLB entries.
Disable MMU initialization option for known MMUv2 cores so that they get
correct kernel load/start address by default.
This fixes the default allmodconfig build.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-29 12:55:00 -07:00
Al Viro
76580237d1 xtensa: split uaccess.h into C and asm sides
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:15:21 -04:00
Al Viro
df720ac12f exceptions: detritus removal
externs and defines for stuff that is never used

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:15:14 -04:00
Max Filippov
5b8b3c860b xtensa: add default memmap and mmio32native options to defconfigs
Now that memory initialization doesn't add default memory region
specify it explicitly in the memmap command line option in case somebody
wants to boot in non-DT-enabled configuration.

While at it update earlycon access mode to mmio32native to support both
LE and BE cores transparently.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 20:43:24 -07:00
Max Filippov
6edbbd1675 xtensa: add default memmap option to common_defconfig
Now that memory initialization doesn't add default memory region specify
it explicitly in the memmap command line option.

Save common_defconfig as defconfig so that it doesn't have all option
settings in it, only those that are different from the Kconfig defaults.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 20:43:23 -07:00
Max Filippov
81da313f2c xtensa: add default memmap option to iss_defconfig
Now that memory initialization doesn't add default memory region specify
it explicitly in the memmap command line option.

Save iss_defconfig as defconfig so that it doesn't have all option
settings in it, only those that are different from the Kconfig defaults.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 20:43:23 -07:00
Max Filippov
549409b4b5 xtensa: ISS: allow simdisk to use high memory buffers
ISS kernel by default has only low memory. But it may be configured to
support high memory and started in a simulator with more than 128M of
RAM. Simdisk driver in such configuration can get IO request with a
high memory page. There may be no TLB entry for that page, only page
table entry. However simulators don't do pagewalking, so such IO request
will fail. Touch IO buffer in the buffer read/write loop so that a TLB
entry is likely there when read or write simcall is invoked.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 20:43:22 -07:00
Max Filippov
feec273a2b xtensa: ISS: define simc_exit and use it instead of inline asm
A number of ISS platform functions use inline assembly to invoke
simulator exit, not all correctly. Define simc_exit(exit_code) and use
it instead of inline assembly.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 18:53:00 -07:00
Max Filippov
70feca7199 xtensa: xtfpga: group platform_* functions together
Group platform_* functions together and turn two separate #ifdef/#ifndef
blocks into single #ifdef/#else. No functional changes.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 18:52:59 -07:00
Max Filippov
205ad548a7 xtensa: rearrange CCOUNT calibration
DT-enabled kernel should have a CPU node connected to a clock. This clock
is the CCOUNT clock. Use old platform_calibrate_ccount call as a fallback
when CPU node cannot be found or has no clock and in non-DT-enabled
configurations.

Drop no longer needed code that updates CPU clock-frequency property in
the DT; drop DT-related code from the platform_calibrate_ccount too.

Move of_clk_init to the top of time_init, so that clocks are initialized
before CCOUNT calibration is attempted.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-20 18:52:59 -07:00
Max Filippov
58c3e3ac7a xtensa: xtfpga: use clock provider, don't update DT
Instead of querying hardcoded FPGA frequency register and then updating
clock-frequency property in specificly named DT nodes in machine setup
code register a clock provider that returns fixed-rate clock, configured
by register specified in DT. This way we have less magic/hardcoded names
and use more existing common clock framework code.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
2016-09-20 18:52:51 -07:00
Scott Telford
bebbc4bcf3 xtensa: Tweak xuartps UART driver Rx watermark for Cadence CSP config.
Add module parameter xilinx_uartps.rx_trigger_level=32 to command line
options for CSP to set Rx watermark for xuartps driver lower than the
default value, to avoid UART overruns at 115200 bps.

Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-19 11:51:32 -07:00
Max Filippov
bf15f86b34 xtensa: initialize MMU before jumping to reset vector
When reset is simulated MMU need to be brought into its initial state,
because that's what bootloaders/OS kernels assume. This is especially
important for MMUv3 because TLB state when the kernel is running is
significatly different from its reset state.

With this change it is possible to boot linux and get back to U-Boot
repeatedly.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-11 23:53:23 -07:00
Max Filippov
ea951c34ea xtensa: fix icountlevel setting in cpu_reset
icountlevel SR value specifies lowest intlevel that does not do
instruction counting, so to disable instruction counting completely it
must be set to 0, not to 15.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-11 23:53:22 -07:00
Max Filippov
4f2056873f xtensa: extract common CPU reset code into separate function
platform_restart implementatations do the same thing to reset CPU.
Don't duplicate that code, move it to a function and call it from
platform_restart.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-11 23:53:22 -07:00
Scott Telford
23c2b9321b xtensa: Added Cadence CSP kernel configuration for Xtensa
Added defconfig, device tree and Xtensa variant header files for the
Cadence Configurable System Platform "xt_lnx" processor configuration.

Signed-off-by: Scott Telford <stelford@cadence.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-09 18:39:09 -07:00
Max Filippov
73a3eed0a4 xtensa: fix default kernel load address
Make default kernel load address 0xd0003000 for MMUv2 cores and
0x60003000 for noMMU cores. Don't initialize MMU inside vmlinux for
predefined MMUv2 cores (it's noop anyway).

This fixes the following defconfig build error:
  arch/xtensa/kernel/built-in.o: In function `fast_alloca':
  (.text+0x99a): dangerous relocation: j: cannot encode: _WindowUnderflow12
  arch/xtensa/kernel/built-in.o: In function `fast_alloca':
  (.text+0x99d): dangerous relocation: j: cannot encode: _WindowUnderflow8
  arch/xtensa/kernel/built-in.o: In function `fast_alloca':
  (.text+0x9a0): dangerous relocation: j: cannot encode: _WindowUnderflow4
  arch/xtensa/kernel/built-in.o: In function `window_overflow_restore_a0_fixup':
  (.text+0x23a3): dangerous relocation: j: cannot encode: (.DoubleExceptionVector.text+0x104)
  arch/xtensa/kernel/built-in.o: In function `window_overflow_restore_a0_fixup':
  (.text+0x23c1): dangerous relocation: j: cannot encode: (.DoubleExceptionVector.text+0x104)
  arch/xtensa/kernel/built-in.o: In function `window_overflow_restore_a0_fixup':
  (.text+0x23dd): dangerous relocation: j: cannot encode: (.DoubleExceptionVector.text+0x104)

With this change all xtensa defconfigs build correctly.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-09-09 18:38:35 -07:00
Dave Hansen
e8c24d3a23 x86/pkeys: Allocation/free syscalls
This patch adds two new system calls:

	int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
	int pkey_free(int pkey);

These implement an "allocator" for the protection keys
themselves, which can be thought of as analogous to the allocator
that the kernel has for file descriptors.  The kernel tracks
which numbers are in use, and only allows operations on keys that
are valid.  A key which was not obtained by pkey_alloc() may not,
for instance, be passed to pkey_mprotect().

These system calls are also very important given the kernel's use
of pkeys to implement execute-only support.  These help ensure
that userspace can never assume that it has control of a key
unless it first asks the kernel.  The kernel does not promise to
preserve PKRU (right register) contents except for allocated
pkeys.

The 'init_access_rights' argument to pkey_alloc() specifies the
rights that will be established for the returned pkey.  For
instance:

	pkey = pkey_alloc(flags, PKEY_DENY_WRITE);

will allocate 'pkey', but also sets the bits in PKRU[1] such that
writing to 'pkey' is already denied.

The kernel does not prevent pkey_free() from successfully freeing
in-use pkeys (those still assigned to a memory range by
pkey_mprotect()).  It would be expensive to implement the checks
for this, so we instead say, "Just don't do it" since sane
software will never do it anyway.

Any piece of userspace calling pkey_alloc() needs to be prepared
for it to fail.  Why?  pkey_alloc() returns the same error code
(ENOSPC) when there are no pkeys and when pkeys are unsupported.
They can be unsupported for a whole host of reasons, so apps must
be prepared for this.  Also, libraries or LD_PRELOADs might steal
keys before an application gets access to them.

This allocation mechanism could be implemented in userspace.
Even if we did it in userspace, we would still need additional
user/kernel interfaces to tell userspace which keys are being
used by the kernel internally (such as for execute-only
mappings).  Having the kernel provide this facility completely
removes the need for these additional interfaces, or having an
implementation of this in userspace at all.

Note that we have to make changes to all of the architectures
that do not use mman-common.h because we use the new
PKEY_DENY_ACCESS/WRITE macros in arch-independent code.

1. PKRU is the Protection Key Rights User register.  It is a
   usermode-accessible register that controls whether writes
   and/or access to each individual pkey is allowed or denied.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: linux-arch@vger.kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: arnd@arndb.de
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/20160729163015.444FE75F@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-09 13:02:27 +02:00
Krzysztof Kozlowski
00085f1efa dma-mapping: use unsigned long for dma_attrs
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00