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  1. 14 7月, 2011 2 次提交
  3. 07 6月, 2011 1 次提交
    • A
      x86-64: Emulate legacy vsyscalls · 5cec93c2
      由 Andy Lutomirski 提交于 
      There's a fair amount of code in the vsyscall page.  It contains
a syscall instruction (in the gettimeofday fallback) and who
knows what will happen if an exploit jumps into the middle of
some other code.

Reduce the risk by replacing the vsyscalls with short magic
incantations that cause the kernel to emulate the real
vsyscalls. These incantations are useless if entered in the
middle.

This causes vsyscalls to be a little more expensive than real
syscalls.  Fortunately sensible programs don't use them.
The only exception is time() which is still called by glibc
through the vsyscall - but calling time() millions of times
per second is not sensible. glibc has this fixed in the
development tree.

This patch is not perfect: the vread_tsc and vread_hpet
functions are still at a fixed address.  Fixing that might
involve making alternative patching work in the vDSO.
Signed-off-by: NAndy Lutomirski <luto@mit.edu>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/e64e1b3c64858820d12c48fa739efbd1485e79d5.1307292171.git.luto@mit.edu
[ Removed the CONFIG option - it's simpler to just do it unconditionally. Tidied up the code as well. ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      5cec93c2
  5. 06 6月, 2011 7 次提交
  7. 30 5月, 2011 3 次提交
  9. 29 5月, 2011 6 次提交
    • L
      x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param · 5d4c47e0
      由 Len Brown 提交于 
      mwait_idle() is a C1-only idle loop intended to be more efficient
than HLT on SMP hardware that supports it.

But mwait_idle() has been replaced by the more general
mwait_idle_with_hints(), which handles both C1 and deeper C-states.
ACPI uses only mwait_idle_with_hints(), and never uses mwait_idle().

Deprecate mwait_idle() and the "idle=mwait" cmdline param
to simplify the x86 idle code.

After this change, kernels configured with
(!CONFIG_ACPI=n && !CONFIG_INTEL_IDLE=n) when run on hardware
that support MWAIT will simply use HLT.  If MWAIT is desired
on those systems, cpuidle and the cpuidle drivers above
can be used.

cc: x86@kernel.org
cc: stable@kernel.org # .39.x
Signed-off-by: NLen Brown <len.brown@intel.com>
      5d4c47e0
    • L
      x86 idle: deprecate "no-hlt" cmdline param · cdaab4a0
      由 Len Brown 提交于 
      We'd rather that modern machines not check if HLT works on
every entry into idle, for the benefit of machines that had
marginal electricals 15-years ago.  If those machines are still running
the upstream kernel, they can use "idle=poll".  The only difference
will be that they'll now invoke HLT in machine_hlt().

cc: x86@kernel.org # .39.x
Signed-off-by: NLen Brown <len.brown@intel.com>
      cdaab4a0
    • L
      x86 idle APM: deprecate CONFIG_APM_CPU_IDLE · 99c63221
      由 Len Brown 提交于 
      We don't want to export the pm_idle function pointer to modules.
Currently CONFIG_APM_CPU_IDLE w/ CONFIG_APM_MODULE forces us to.

CONFIG_APM_CPU_IDLE is of dubious value, it runs only on 32-bit
uniprocessor laptops that are over 10 years old.  It calls into
the BIOS during idle, and is known to cause a number of machines
to fail.

Removing CONFIG_APM_CPU_IDLE and will allow us to stop exporting
pm_idle.  Any systems that were calling into the APM BIOS
at run-time will simply use HLT instead.

cc: x86@kernel.org
cc: Jiri Kosina <jkosina@suse.cz>
cc: stable@kernel.org # .39.x
Signed-off-by: NLen Brown <len.brown@intel.com>
      99c63221
    • L
      x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it · 06ae40ce
      由 Len Brown 提交于 
      In the long run, we don't want default_idle() or (pm_idle)() to
be exported outside of process.c.  Start by not exporting them
to modules, unless the APM build demands it.

cc: x86@kernel.org
cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>
      06ae40ce
    • L
      x86 idle: clarify AMD erratum 400 workaround · 02c68a02
      由 Len Brown 提交于 
      The workaround for AMD erratum 400 uses the term "c1e" falsely suggesting:
1. Intel C1E is somehow involved
2. All AMD processors with C1E are involved

Use the string "amd_c1e" instead of simply "c1e" to clarify that
this workaround is specific to AMD's version of C1E.
Use the string "e400" to clarify that the workaround is specific
to AMD processors with Erratum 400.

This patch is text-substitution only, with no functional change.

cc: x86@kernel.org
Acked-by: NBorislav Petkov <borislav.petkov@amd.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
      02c68a02
    • E
      ns: Wire up the setns system call · 7b21fddd
      由 Eric W. Biederman 提交于 
      32bit and 64bit on x86 are tested and working.  The rest I have looked
at closely and I can't find any problems.

setns is an easy system call to wire up.  It just takes two ints so I
don't expect any weird architecture porting problems.

While doing this I have noticed that we have some architectures that are
very slow to get new system calls.  cris seems to be the slowest where
the last system calls wired up were preadv and pwritev.  avr32 is weird
in that recvmmsg was wired up but never declared in unistd.h.  frv is
behind with perf_event_open being the last syscall wired up.  On h8300
the last system call wired up was epoll_wait.  On m32r the last system
call wired up was fallocate.  mn10300 has recvmmsg as the last system
call wired up.  The rest seem to at least have syncfs wired up which was
new in the 2.6.39.

v2: Most of the architecture support added by Daniel Lezcano <dlezcano@fr.ibm.com>
v3: ported to v2.6.36-rc4 by: Eric W. Biederman <ebiederm@xmission.com>
v4: Moved wiring up of the system call to another patch
v5: ported to v2.6.39-rc6
v6: rebased onto parisc-next and net-next to avoid syscall  conflicts.
v7: ported to Linus's latest post 2.6.39 tree.

>  arch/blackfin/include/asm/unistd.h     |    3 ++-
>  arch/blackfin/mach-common/entry.S      |    1 +
Acked-by: NMike Frysinger <vapier@gentoo.org>

Oh - ia64 wiring looks good.
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7b21fddd
  11. 28 5月, 2011 1 次提交
    • S
      x86: Put back -pg to tsc.o and add no GCOV to vread_tsc_64.o · 89e1be50
      由 Steven Rostedt 提交于 
      The commit 44259b1a
    Author: Andy Lutomirski <luto@MIT.EDU>
    x86-64: Move vread_tsc into a new file with sensible options

Removed the -pg from tsc.o which caused the function graph tracer
to go into an infinite function call recursion as it uses the tsc
internally outside its recursion protection, thus tracing the tsc
breaks the function graph tracer.

This commit also added the file vread_tsc_64.c that gets used
by vdso but failed to prevent GCOV from monkeying with it,
causing userspace to try to access kernel data when GCOV was
enabled.

Thanks to Thomas Gleixner for pointing out GCOV as the likely
culprit that added strange kernel accesses into the vread_tsc()
call.

Cc: Author: Andy Lutomirski <luto@MIT.EDU>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      89e1be50
  13. 27 5月, 2011 7 次提交
  15. 26 5月, 2011 6 次提交
  17. 25 5月, 2011 7 次提交