diff options
| author | Jeremy Fitzhardinge <jeremy@goop.org> | 2008-07-01 16:46:37 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-08 13:16:30 +0200 |
| commit | 5a654ba7a88d90483d0f0586297ea9075d755fc8 (patch) | |
| tree | d3832d3d7ba02dd7f39f125536d754fcb2ea0b83 /arch/x86 | |
| parent | ef5e94af16c0c82452e1ea5d387e1203dd2198d6 (diff) | |
x86/cpa: use an undefined PTE bit for testing CPA
Rather than using _PAGE_GLOBAL - which not all CPUs support - to test
CPA, use one of the reserved-for-software-use PTE flags instead. This
allows CPA testing to work on CPUs which don't support PGD.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/mm/pageattr-test.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/arch/x86/mm/pageattr-test.c b/arch/x86/mm/pageattr-test.c index 75f1b109aae..0dcd42eb94e 100644 --- a/arch/x86/mm/pageattr-test.c +++ b/arch/x86/mm/pageattr-test.c @@ -1,8 +1,8 @@ /* * self test for change_page_attr. * - * Clears the global bit on random pages in the direct mapping, then reverts - * and compares page tables forwards and afterwards. + * Clears the a test pte bit on random pages in the direct mapping, + * then reverts and compares page tables forwards and afterwards. */ #include <linux/bootmem.h> #include <linux/kthread.h> @@ -32,6 +32,13 @@ enum { GPS = (1<<30) }; +#define PAGE_TESTBIT __pgprot(_PAGE_UNUSED1) + +static int pte_testbit(pte_t pte) +{ + return pte_flags(pte) & _PAGE_UNUSED1; +} + struct split_state { long lpg, gpg, spg, exec; long min_exec, max_exec; @@ -165,15 +172,14 @@ static int pageattr_test(void) continue; } - err = change_page_attr_clear(addr[i], len[i], - __pgprot(_PAGE_GLOBAL)); + err = change_page_attr_set(addr[i], len[i], PAGE_TESTBIT); if (err < 0) { printk(KERN_ERR "CPA %d failed %d\n", i, err); failed++; } pte = lookup_address(addr[i], &level); - if (!pte || pte_global(*pte) || pte_huge(*pte)) { + if (!pte || !pte_testbit(*pte) || pte_huge(*pte)) { printk(KERN_ERR "CPA %lx: bad pte %Lx\n", addr[i], pte ? (u64)pte_val(*pte) : 0ULL); failed++; @@ -198,14 +204,13 @@ static int pageattr_test(void) failed++; continue; } - err = change_page_attr_set(addr[i], len[i], - __pgprot(_PAGE_GLOBAL)); + err = change_page_attr_clear(addr[i], len[i], PAGE_TESTBIT); if (err < 0) { printk(KERN_ERR "CPA reverting failed: %d\n", err); failed++; } pte = lookup_address(addr[i], &level); - if (!pte || !pte_global(*pte)) { + if (!pte || pte_testbit(*pte)) { printk(KERN_ERR "CPA %lx: bad pte after revert %Lx\n", addr[i], pte ? (u64)pte_val(*pte) : 0ULL); failed++; |