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| author | Andy Lutomirski <luto@amacapital.net> | 2014-10-24 15:58:07 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-02-04 12:10:41 +0100 |
| commit | 375074cc736ab1d89a708c0a8d7baa4a70d5d476 (patch) | |
| tree | e7ceb81f6fc54814fc57716a79f8d232f5e6afb8 /drivers/lguest | |
| parent | 0967160ad615985c7c35443156ea9aecc60c37b8 (diff) | |
| download | lwn-375074cc736ab1d89a708c0a8d7baa4a70d5d476.tar.gz lwn-375074cc736ab1d89a708c0a8d7baa4a70d5d476.zip | |
x86: Clean up cr4 manipulation
CR4 manipulation was split, seemingly at random, between direct
(write_cr4) and using a helper (set/clear_in_cr4). Unfortunately,
the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code,
which only a small subset of users actually wanted.
This patch replaces all cr4 access in functions that don't leave cr4
exactly the way they found it with new helpers cr4_set_bits,
cr4_clear_bits, and cr4_set_bits_and_update_boot.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/lguest')
| -rw-r--r-- | drivers/lguest/x86/core.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index 922a1acbf652..6adfd7ba4c97 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -47,6 +47,7 @@ #include <asm/lguest.h> #include <asm/uaccess.h> #include <asm/i387.h> +#include <asm/tlbflush.h> #include "../lg.h" static int cpu_had_pge; @@ -452,9 +453,9 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu) static void adjust_pge(void *on) { if (on) - write_cr4(read_cr4() | X86_CR4_PGE); + cr4_set_bits(X86_CR4_PGE); else - write_cr4(read_cr4() & ~X86_CR4_PGE); + cr4_clear_bits(X86_CR4_PGE); } /*H:020 |