According to Appendix F, the TLB is the primary arbiter of speculation.
Thus, if a page has a TLB entry, it may be speculatively read into the
cache. On linux, this can cause us incoherencies because if we're about
to do a disk read, we call get_user_pages() to do the flush/invalidate
in user space, but we still potentially have the user TLB entries, and
the cache could speculate the lines back into userspace (thus causing
stale data to be used). This is fixed by purging the TLB entries before
we flush through the tmpalias space. Now, the only way the line could
be re-speculated is if the user actually tries to touch it (which is not
allowed).
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Currently parisc has the whole kernel marked as RWX, meaning any
kernel page at all is eligible to be executed. This can cause a
theoretical problem on systems with combined I/D TLB because the act
of referencing a page causes a TLB insertion with an executable bit.
This TLB entry may be used by the CPU as the basis for speculating the
page into the I-Cache. If this speculated page is subsequently used
for a user process, there is the possibility we will get a stale
I-cache line picked up as the binary executes.
As a point of good practise, only mark actual kernel text pages as
executable. The same has to be done for init_text pages, but they're
converted to data pages (and the I-Cache flushed) when the init memory
is released.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
minix bit operations are only used by minix filesystem and useless by
other modules. Because byte order of inode and block bitmaps is different
on each architecture like below:
m68k:
big-endian 16bit indexed bitmaps
h8300, microblaze, s390, sparc, m68knommu:
big-endian 32 or 64bit indexed bitmaps
m32r, mips, sh, xtensa:
big-endian 32 or 64bit indexed bitmaps for big-endian mode
little-endian bitmaps for little-endian mode
Others:
little-endian bitmaps
In order to move minix bit operations from asm/bitops.h to architecture
independent code in minix filesystem, this provides two config options.
CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED is only selected by m68k.
CONFIG_MINIX_FS_NATIVE_ENDIAN is selected by the architectures which use
native byte order bitmaps (h8300, microblaze, s390, sparc, m68knommu,
m32r, mips, sh, xtensa). The architectures which always use little-endian
bitmaps do not select these options.
Finally, we can remove minix bit operations from asm/bitops.h for all
architectures.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As the result of conversions, there are no users of ext2 non-atomic bit
operations except for ext2 filesystem itself. Now we can put them into
architecture independent code in ext2 filesystem, and remove from
asm/bitops.h for all architectures.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] Convert to new irq_chip functions
[PARISC] fix per-cpu flag problem in the cpu affinity checkers
[PARISC] fix vmap flush/invalidate
eliminate special FLUSH flag from page table
parisc: flush pages through tmpalias space
Make __get_user_pages return -EHWPOISON for HWPOISON page only if
FOLL_HWPOISON is specified. With this patch, the interested callers
can distinguish HWPOISON pages from general FAULT pages, while other
callers will still get -EFAULT for all these pages, so the user space
interface need not to be changed.
This feature is needed by KVM, where UCR MCE should be relayed to
guest for HWPOISON page, while instruction emulation and MMIO will be
tried for general FAULT page.
The idea comes from Andrew Morton.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (76 commits)
pch_uart: reference clock on CM-iTC
pch_phub: add new device ML7213
n_gsm: fix UIH control byte : P bit should be 0
n_gsm: add a documentation
serial: msm_serial_hs: Add MSM high speed UART driver
tty_audit: fix tty_audit_add_data live lock on audit disabled
tty: move cd1865.h to drivers/staging/tty/
Staging: tty: fix build with epca.c driver
pcmcia: synclink_cs: fix prototype for mgslpc_ioctl()
Staging: generic_serial: fix double locking bug
nozomi: don't use flush_scheduled_work()
tty/serial: Relax the device_type restriction from of_serial
MAINTAINERS: Update HVC file patterns
tty: phase out of ioctl file pointer for tty3270 as well
tty: forgot to remove ipwireless from drivers/char/pcmcia/Makefile
pch_uart: Fix DMA channel miss-setting issue.
pch_uart: fix exclusive access issue
pch_uart: fix auto flow control miss-setting issue
pch_uart: fix uart clock setting issue
pch_uart : Use dev_xxx not pr_xxx
...
Fix up trivial conflicts in drivers/misc/pch_phub.c (same patch applied
twice, then changes to the same area in one branch)
[AV: on architectures where default conflicts with existing
flags, that is]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This is useful for system management software so that it can kick
off things like gettys and everything that's started from a tty,
before we reuse it from/for something else or shut it down.
Without this ioctl it would have to temporarily become the owner of
the tty, then call vhangup() and then give it up again.
Cc: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Convert all the parisc driver interrupt handlers (dino, eisa, gsc,
iosapic and superio) as well as the cpu interrupts. Prepare
show_interrupts for GENERIC_HARDIRQS_NO_DEPRECATED and finally selects
that Kconfig option
[jejb: compile and testing fixes]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
On parisc, we never implemented invalidate_kernel_vmap_range() because
it was unnecessary for the xfs use case. However, we do need to
implement an invalidate for the opposite use case (which occurred in a
recent NFS change) where the user wants to read through the vmap range
and write via the kernel address. There's an additional complexity to
this in that if the page has no userspace mappings, it might have dirty
cache lines in the kernel (indicated by the PG_dcache_dirty bit). In
order to get full coherency, we need to flush these pages through the
kernel mapping before invalidating the vmap range.
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
James Bottomley
James Bottomley
Lucas De Marchi
FUJITA Tomonori
Akinobu Mita
Linus Torvalds
Huang Ying
Stephen Rothwell
Michel Lespinasse
Kay Sievers
James Bottomley
Thomas Gleixner