Pull arch/c6x fixes from Mark Salter.

* tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming:
  c6x: platforms: cache: Export symbol L1P_cache_block_invalidate and L1D_cache_block_writeback
  c6x: kernel: setup: Export symbol memory_end
  c6x: kernel: setup: Add screen_info global variable
  c6x: include: asm: Kbuild: Add generic serial.h
  c6x: include: asm: dma-mapping: Add dummy dma_sync_single_range_for_device
  c6x: include: asm: setup: Include "linux/types.h"
  c6x: asm: Add default flat.h according to xtensa architecture
  c6x: kernel: setup: Remove 'const' for local variables in machine_init
  c6x: Makefile: Add -D__linux__
  C6x: time: Ensure consistency in __init
  c6x: kernel: setup: Include "linux/console.h"

flush_old_exec() has already done that.  Back on 2011 a bunch of
instances like that had been kicked out, but that hadn't taken
care of then-out-of-tree architectures, obviously, and they served
as reinfection vector...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

It is needed by several modules, the related error with allmodconfig:

    MODPOST 3327 modules
  ERROR: "memory_end" [net/wireless/lib80211_crypt_tkip.ko] undefined!
  ERROR: "memory_end" [net/sunrpc/sunrpc.ko] undefined!
  ERROR: "memory_end" [net/sunrpc/auth_gss/rpcsec_gss_krb5.ko] undefined!
  ERROR: "memory_end" [net/rxrpc/rxkad.ko] undefined!
  ERROR: "memory_end" [net/mac802154/mac802154.ko] undefined!
  ERROR: "memory_end" [net/mac80211/mac80211.ko] undefined!
  ERROR: "memory_end" [net/ipv6/esp6.ko] undefined!
  ERROR: "memory_end" [net/ipv6/ah6.ko] undefined!
  ERROR: "memory_end" [net/ipv4/esp4.ko] undefined!
  ERROR: "memory_end" [net/ipv4/ah4.ko] undefined!
  ERROR: "memory_end" [net/ceph/libceph.ko] undefined!
  ERROR: "memory_end" [net/9p/9pnet_virtio.ko] undefined!
  ERROR: "memory_end" [drivers/usb/wusbcore/wusbcore.ko] undefined!
  ERROR: "memory_end" [drivers/usb/misc/usbtest.ko] undefined!
  ERROR: "memory_end" [drivers/usb/core/usbcore.ko] undefined!
  ERROR: "memory_end" [drivers/target/target_core_file.ko] undefined!
  ERROR: "memory_end" [drivers/net/wireless/brcm80211/brcmfmac/brcmfmac.ko] undefined!
  ERROR: "memory_end" [drivers/net/wireless/ath/ath6kl/ath6kl_sdio.ko] undefined!
  ERROR: "memory_end" [drivers/net/virtio_net.ko] undefined!
  ERROR: "memory_end" [drivers/net/usb/usbnet.ko] undefined!
  ERROR: "memory_end" [drivers/net/ppp/ppp_mppe.ko] undefined!
  ERROR: "memory_end" [drivers/mtd/nand/nand.ko] undefined!
  ERROR: "memory_end" [drivers/mmc/card/mmc_block.ko] undefined!
  ERROR: "memory_end" [drivers/crypto/qce/qcrypto.ko] undefined!
  ERROR: "memory_end" [drivers/block/drbd/drbd.ko] undefined!
  ERROR: "memory_end" [drivers/block/aoe/aoe.ko] undefined!
  ERROR: "memory_end" [crypto/tcrypt.ko] undefined!
  ERROR: "memory_end" [crypto/gcm.ko] undefined!
  ERROR: "memory_end" [crypto/cts.ko] undefined!
  ERROR: "memory_end" [crypto/ccm.ko] undefined!
  ERROR: "memory_end" [crypto/authencesn.ko] undefined!
  ERROR: "memory_end" [crypto/authenc.ko] undefined!

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Mark Salter <msalter@redhat.com>

Or can not pass building with allmodconfig:

    LD      init/built-in.o
  drivers/built-in.o: In function `vgacon_switch':
  vgacon.c:(.text+0x47f8): undefined reference to `screen_info'
  vgacon.c:(.text+0x4810): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_resize':
  vgacon.c:(.text+0x4ac8): undefined reference to `screen_info'
  vgacon.c:(.text+0x4acc): undefined reference to `screen_info'
  drivers/built-in.o: In function `vgacon_save_screen':
  vgacon.c:(.text+0x4cc8): undefined reference to `screen_info'
  drivers/built-in.o:vgacon.c:(.text+0x4cd0): more undefined references to `screen_info' follow

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Mark Salter <msalter@redhat.com>

early_init_dt_scan() accepts "void *", the related warning:

    CC      arch/c6x/kernel/setup.o
  arch/c6x/kernel/setup.c: In function 'machine_init':
  arch/c6x/kernel/setup.c:290:21: warning: passing argument 1 of 'early_init_dt_scan' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
    early_init_dt_scan(fdt);
                       ^
  In file included from arch/c6x/kernel/setup.c:19:0:
  include/linux/of_fdt.h:75:13: note: expected 'void *' but argument is of type 'const void *'
   extern bool early_init_dt_scan(void *params);
               ^

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Mark Salter <msalter@redhat.com>

time_init invokes timer64_init (which is __init annotation)
since all of these are invoked at init time, lets maintain
consistency by ensuring time_init is marked appropriately
as well.

This fixes the following warning with CONFIG_DEBUG_SECTION_MISMATCH=y

WARNING: vmlinux.o(.text+0x3bfc): Section mismatch in reference from the function time_init() to the function .init.text:timer64_init()
The function time_init() references
the function __init timer64_init().
This is often because time_init lacks a __init
annotation or the annotation of timer64_init is wrong.

Fixes: 546a39546c64 ("C6X: time management")
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>

Or c6x will cause building break for allmodconfig, the related error:

    CC      arch/c6x/kernel/setup.o
  arch/c6x/kernel/setup.c: In function 'setup_arch':
  arch/c6x/kernel/setup.c:433:2: error: 'conswitchp' undeclared (first use in this function)
    conswitchp = &dummy_con;
    ^
  arch/c6x/kernel/setup.c:433:2: note: each undeclared identifier is reported only once for each function it appears in
  arch/c6x/kernel/setup.c:433:16: error: 'dummy_con' undeclared (first use in this function)
    conswitchp = &dummy_con;
                  ^

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
[removed unnecessary #ifdef around include]
Signed-off-by: Mark Salter <msalter@redhat.com>

If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use sigsp() instead of the open coded variant.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Mark Salter <msalter@redhat.com>

Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Tested-by: Mark Salter <msalter@redhat.com>
Acked-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Richard Weinberger <richard@nod.at>