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authorLinus Torvalds <torvalds@linux-foundation.org>2008-04-21 15:38:43 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-04-21 15:38:43 -0700
commit5f033bb9bc5cb3bb37a79e3ef131f50ecdcb72b0 (patch)
tree16c6fdc3fab80d88ea4d8fd7eb302097f97c062c /Documentation
parentfd9be4ce2e1eb407a8152f823698cc0d652bbec8 (diff)
parent34d0559178393547505ec9492321255405f4e441 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86: (77 commits) x86: UV startup of slave cpus x86: integrate pci-dma.c x86: don't do dma if mask is NULL. x86: return conditional to mmu x86: remove kludge from x86_64 x86: unify gfp masks x86: retry allocation if failed x86: don't try to allocate from DMA zone at first x86: use a fallback dev for i386 x86: use numa allocation function in i386 x86: remove virt_to_bus in pci-dma_64.c x86: adjust dma_free_coherent for i386 x86: move bad_dma_address x86: isolate coherent mapping functions x86: move dma_coherent functions to pci-dma.c x86: merge iommu initialization parameters x86: merge dma_supported x86: move pci fixup to pci-dma.c x86: move x86_64-specific to common code. x86: move initialization functions to pci-dma.c ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/feature-removal-schedule.txt7
-rw-r--r--Documentation/kernel-parameters.txt10
-rw-r--r--Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c96
-rw-r--r--Documentation/prctl/disable-tsc-on-off-stress-test.c95
-rw-r--r--Documentation/prctl/disable-tsc-test.c94
5 files changed, 301 insertions, 1 deletions
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index af0e9393bf6..309c47b9159 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -282,6 +282,13 @@ Why: Not used in-tree. The current out-of-tree users used it to
out-of-tree driver.
Who: Thomas Gleixner <tglx@linutronix.de>
+----------------------------
+
+What: usedac i386 kernel parameter
+When: 2.6.27
+Why: replaced by allowdac and no dac combination
+Who: Glauber Costa <gcosta@redhat.com>
+
---------------------------
What: /sys/o2cb symlink
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 4b0f1ae31a4..f4839606988 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1280,8 +1280,16 @@ and is between 256 and 4096 characters. It is defined in the file
noexec [IA-64]
noexec [X86-32,X86-64]
+ On X86-32 available only on PAE configured kernels.
noexec=on: enable non-executable mappings (default)
- noexec=off: disable nn-executable mappings
+ noexec=off: disable non-executable mappings
+
+ noexec32 [X86-64]
+ This affects only 32-bit executables.
+ noexec32=on: enable non-executable mappings (default)
+ read doesn't imply executable mappings
+ noexec32=off: disable non-executable mappings
+ read implies executable mappings
nofxsr [BUGS=X86-32] Disables x86 floating point extended
register save and restore. The kernel will only save
diff --git a/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c b/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c
new file mode 100644
index 00000000000..f8e8e95e81f
--- /dev/null
+++ b/Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c
@@ -0,0 +1,96 @@
+/*
+ * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
+ *
+ * Tests if the control register is updated correctly
+ * at context switches
+ *
+ * Warning: this test will cause a very high load for a few seconds
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <inttypes.h>
+#include <wait.h>
+
+
+#include <sys/prctl.h>
+#include <linux/prctl.h>
+
+/* Get/set the process' ability to use the timestamp counter instruction */
+#ifndef PR_GET_TSC
+#define PR_GET_TSC 25
+#define PR_SET_TSC 26
+# define PR_TSC_ENABLE 1 /* allow the use of the timestamp counter */
+# define PR_TSC_SIGSEGV 2 /* throw a SIGSEGV instead of reading the TSC */
+#endif
+
+uint64_t rdtsc() {
+uint32_t lo, hi;
+/* We cannot use "=A", since this would use %rax on x86_64 */
+__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+return (uint64_t)hi << 32 | lo;
+}
+
+void sigsegv_expect(int sig)
+{
+ /* */
+}
+
+void segvtask(void)
+{
+ if (prctl(PR_SET_TSC, PR_TSC_SIGSEGV) < 0)
+ {
+ perror("prctl");
+ exit(0);
+ }
+ signal(SIGSEGV, sigsegv_expect);
+ alarm(10);
+ rdtsc();
+ fprintf(stderr, "FATAL ERROR, rdtsc() succeeded while disabled\n");
+ exit(0);
+}
+
+
+void sigsegv_fail(int sig)
+{
+ fprintf(stderr, "FATAL ERROR, rdtsc() failed while enabled\n");
+ exit(0);
+}
+
+void rdtsctask(void)
+{
+ if (prctl(PR_SET_TSC, PR_TSC_ENABLE) < 0)
+ {
+ perror("prctl");
+ exit(0);
+ }
+ signal(SIGSEGV, sigsegv_fail);
+ alarm(10);
+ for(;;) rdtsc();
+}
+
+
+int main(int argc, char **argv)
+{
+ int n_tasks = 100, i;
+
+ fprintf(stderr, "[No further output means we're allright]\n");
+
+ for (i=0; i<n_tasks; i++)
+ if (fork() == 0)
+ {
+ if (i & 1)
+ segvtask();
+ else
+ rdtsctask();
+ }
+
+ for (i=0; i<n_tasks; i++)
+ wait(NULL);
+
+ exit(0);
+}
+
diff --git a/Documentation/prctl/disable-tsc-on-off-stress-test.c b/Documentation/prctl/disable-tsc-on-off-stress-test.c
new file mode 100644
index 00000000000..1fcd9144537
--- /dev/null
+++ b/Documentation/prctl/disable-tsc-on-off-stress-test.c
@@ -0,0 +1,95 @@
+/*
+ * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
+ *
+ * Tests if the control register is updated correctly
+ * when set with prctl()
+ *
+ * Warning: this test will cause a very high load for a few seconds
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <inttypes.h>
+#include <wait.h>
+
+
+#include <sys/prctl.h>
+#include <linux/prctl.h>
+
+/* Get/set the process' ability to use the timestamp counter instruction */
+#ifndef PR_GET_TSC
+#define PR_GET_TSC 25
+#define PR_SET_TSC 26
+# define PR_TSC_ENABLE 1 /* allow the use of the timestamp counter */
+# define PR_TSC_SIGSEGV 2 /* throw a SIGSEGV instead of reading the TSC */
+#endif
+
+/* snippet from wikipedia :-) */
+
+uint64_t rdtsc() {
+uint32_t lo, hi;
+/* We cannot use "=A", since this would use %rax on x86_64 */
+__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+return (uint64_t)hi << 32 | lo;
+}
+
+int should_segv = 0;
+
+void sigsegv_cb(int sig)
+{
+ if (!should_segv)
+ {
+ fprintf(stderr, "FATAL ERROR, rdtsc() failed while enabled\n");
+ exit(0);
+ }
+ if (prctl(PR_SET_TSC, PR_TSC_ENABLE) < 0)
+ {
+ perror("prctl");
+ exit(0);
+ }
+ should_segv = 0;
+
+ rdtsc();
+}
+
+void task(void)
+{
+ signal(SIGSEGV, sigsegv_cb);
+ alarm(10);
+ for(;;)
+ {
+ rdtsc();
+ if (should_segv)
+ {
+ fprintf(stderr, "FATAL ERROR, rdtsc() succeeded while disabled\n");
+ exit(0);
+ }
+ if (prctl(PR_SET_TSC, PR_TSC_SIGSEGV) < 0)
+ {
+ perror("prctl");
+ exit(0);
+ }
+ should_segv = 1;
+ }
+}
+
+
+int main(int argc, char **argv)
+{
+ int n_tasks = 100, i;
+
+ fprintf(stderr, "[No further output means we're allright]\n");
+
+ for (i=0; i<n_tasks; i++)
+ if (fork() == 0)
+ task();
+
+ for (i=0; i<n_tasks; i++)
+ wait(NULL);
+
+ exit(0);
+}
+
diff --git a/Documentation/prctl/disable-tsc-test.c b/Documentation/prctl/disable-tsc-test.c
new file mode 100644
index 00000000000..843c81eac23
--- /dev/null
+++ b/Documentation/prctl/disable-tsc-test.c
@@ -0,0 +1,94 @@
+/*
+ * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
+ *
+ * Basic test to test behaviour of PR_GET_TSC and PR_SET_TSC
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <inttypes.h>
+
+
+#include <sys/prctl.h>
+#include <linux/prctl.h>
+
+/* Get/set the process' ability to use the timestamp counter instruction */
+#ifndef PR_GET_TSC
+#define PR_GET_TSC 25
+#define PR_SET_TSC 26
+# define PR_TSC_ENABLE 1 /* allow the use of the timestamp counter */
+# define PR_TSC_SIGSEGV 2 /* throw a SIGSEGV instead of reading the TSC */
+#endif
+
+const char *tsc_names[] =
+{
+ [0] = "[not set]",
+ [PR_TSC_ENABLE] = "PR_TSC_ENABLE",
+ [PR_TSC_SIGSEGV] = "PR_TSC_SIGSEGV",
+};
+
+uint64_t rdtsc() {
+uint32_t lo, hi;
+/* We cannot use "=A", since this would use %rax on x86_64 */
+__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
+return (uint64_t)hi << 32 | lo;
+}
+
+void sigsegv_cb(int sig)
+{
+ int tsc_val = 0;
+
+ printf("[ SIG_SEGV ]\n");
+ printf("prctl(PR_GET_TSC, &tsc_val); ");
+ fflush(stdout);
+
+ if ( prctl(PR_GET_TSC, &tsc_val) == -1)
+ perror("prctl");
+
+ printf("tsc_val == %s\n", tsc_names[tsc_val]);
+ printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n");
+ fflush(stdout);
+ if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1)
+ perror("prctl");
+
+ printf("rdtsc() == ");
+}
+
+int main(int argc, char **argv)
+{
+ int tsc_val = 0;
+
+ signal(SIGSEGV, sigsegv_cb);
+
+ printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
+ printf("prctl(PR_GET_TSC, &tsc_val); ");
+ fflush(stdout);
+
+ if ( prctl(PR_GET_TSC, &tsc_val) == -1)
+ perror("prctl");
+
+ printf("tsc_val == %s\n", tsc_names[tsc_val]);
+ printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
+ printf("prctl(PR_SET_TSC, PR_TSC_ENABLE)\n");
+ fflush(stdout);
+
+ if ( prctl(PR_SET_TSC, PR_TSC_ENABLE) == -1)
+ perror("prctl");
+
+ printf("rdtsc() == %llu\n", (unsigned long long)rdtsc());
+ printf("prctl(PR_SET_TSC, PR_TSC_SIGSEGV)\n");
+ fflush(stdout);
+
+ if ( prctl(PR_SET_TSC, PR_TSC_SIGSEGV) == -1)
+ perror("prctl");
+
+ printf("rdtsc() == ");
+ fflush(stdout);
+ printf("%llu\n", (unsigned long long)rdtsc());
+ fflush(stdout);
+
+ exit(EXIT_SUCCESS);
+}
+