x86, cpa: Fix kernel text RO checks in static_protection()

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Steven Rostedt reported that we are unconditionally making the
kernel text mapping as read-only. i.e., if someone does cpa() to
the kernel text area for setting/clearing any page table
attribute, we unconditionally clear the read-write attribute for
the kernel text mapping that is set at compile time.

We should delay (to forbid the write attribute) and enforce only
after the kernel has mapped the text as read-only.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20091029024820.996634347@sbs-t61.sc.intel.com>
[ marked kernel_set_to_readonly as __read_mostly ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

...

This commit is contained in:

Suresh Siddha 2009-10-28 18:46:56 -08:00 • committed by Ingo Molnar

parent 883242dd0e

commit 502f660466

4 changed files with 9 additions and 6 deletions

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1

arch/x86/include/asm/cacheflush.h

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2

arch/x86/mm/init_32.c

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2

arch/x86/mm/init_64.c

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10

arch/x86/mm/pageattr.c

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