Re: [PATCH v7 25/28] powerpc: Test prefixed instructions in feature fixups

On Tue, May 5, 2020 at 5:15 PM Alistair Popple [off-list ref] wrote:

Hmm, I was hoping to add a tested by but I'm seeing the following failure in
Mambo:

[    1.475459] feature-fixups: test failed at line 730

Based on the name of the test it looks like you probably made a copy/paste
error in ftr_fixup_prefix2_expected. I suspect you probably meant to use the alt
fixup:

globl(ftr_fixup_prefix2_expected)
        or      1,1,1
        .long 0x7000000
        .long 0x0000001
        or      2,2,2

Thanks, I changed from using 0x7000000 to 1 << 26 but missed here.
Changing that fixes this.

Also for some reason these tests (and one of the code-patching tests) aren't
passing on big endian.

Okay, will fix that.

- Alistair

On Friday, 1 May 2020 1:42:17 PM AEST Jordan Niethe wrote:

quoted

Expand the feature-fixups self-tests to includes tests for prefixed
instructions.

Signed-off-by: Jordan Niethe <redacted>
---
v6: New to series
---
 arch/powerpc/lib/feature-fixups-test.S | 68 +++++++++++++++++++++++
 arch/powerpc/lib/feature-fixups.c      | 74 ++++++++++++++++++++++++++
 2 files changed, 142 insertions(+)

diff --git a/arch/powerpc/lib/feature-fixups-test.S

b/arch/powerpc/lib/feature-fixups-test.S index b12168c2447a..6e2da9123a9b
100644

--- a/arch/powerpc/lib/feature-fixups-test.S
+++ b/arch/powerpc/lib/feature-fixups-test.S

@@ -791,3 +791,71 @@ globl(lwsync_fixup_test_expected_SYNC)
 1:   or      1,1,1
      sync

+globl(ftr_fixup_prefix1)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+globl(end_ftr_fixup_prefix1)
+
+globl(ftr_fixup_prefix1_orig)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+
+globl(ftr_fixup_prefix1_expected)
+     or      1,1,1
+     nop
+     nop
+     or      2,2,2
+
+globl(ftr_fixup_prefix2)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+globl(end_ftr_fixup_prefix2)
+
+globl(ftr_fixup_prefix2_orig)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+
+globl(ftr_fixup_prefix2_alt)
+     .long 0x7000000
+     .long 0x0000001
+
+globl(ftr_fixup_prefix2_expected)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000001
+     or      2,2,2
+
+globl(ftr_fixup_prefix3)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+     or      3,3,3
+globl(end_ftr_fixup_prefix3)
+
+globl(ftr_fixup_prefix3_orig)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000000
+     or      2,2,2
+     or      3,3,3
+
+globl(ftr_fixup_prefix3_alt)
+     .long 1 << 26
+     .long 0x0000001
+     nop
+
+globl(ftr_fixup_prefix3_expected)
+     or      1,1,1
+     .long 1 << 26
+     .long 0x0000001
+     nop
+     or      3,3,3

diff --git a/arch/powerpc/lib/feature-fixups.c

b/arch/powerpc/lib/feature-fixups.c index 243011f85287..6fc499b1d63e 100644

--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c

@@ -687,6 +687,75 @@ static void test_lwsync_macros(void)
      }
 }

+#ifdef __powerpc64__
+static void __init test_prefix_patching(void)
+{
+     extern unsigned int ftr_fixup_prefix1[];
+     extern unsigned int end_ftr_fixup_prefix1[];
+     extern unsigned int ftr_fixup_prefix1_orig[];
+     extern unsigned int ftr_fixup_prefix1_expected[];
+     int size = sizeof(unsigned int) * (end_ftr_fixup_prefix1 -

ftr_fixup_prefix1); +
+     fixup.value = fixup.mask = 8;
+     fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix1 + 1);
+     fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix1 + 3);
+     fixup.alt_start_off = fixup.alt_end_off = 0;
+
+     /* Sanity check */
+     check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) == 0);
+
+     patch_feature_section(0, &fixup);
+     check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_expected, size) == 0);
+     check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) != 0);
+}
+
+static void __init test_prefix_alt_patching(void)
+{
+     extern unsigned int ftr_fixup_prefix2[];
+     extern unsigned int end_ftr_fixup_prefix2[];
+     extern unsigned int ftr_fixup_prefix2_orig[];
+     extern unsigned int ftr_fixup_prefix2_expected[];
+     extern unsigned int ftr_fixup_prefix2_alt[];
+     int size = sizeof(unsigned int) * (end_ftr_fixup_prefix2 -
ftr_fixup_prefix2); +
+     fixup.value = fixup.mask = 8;
+     fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix2 + 1);
+     fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix2 + 3);
+     fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix2_alt);
+     fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix2_alt + 2);
+     /* Sanity check */
+     check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) == 0);
+
+     patch_feature_section(0, &fixup);
+     check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_expected, size) == 0);
+     patch_feature_section(0, &fixup);
+     check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) != 0);
+}
+
+static void __init test_prefix_word_alt_patching(void)
+{
+     extern unsigned int ftr_fixup_prefix3[];
+     extern unsigned int end_ftr_fixup_prefix3[];
+     extern unsigned int ftr_fixup_prefix3_orig[];
+     extern unsigned int ftr_fixup_prefix3_expected[];
+     extern unsigned int ftr_fixup_prefix3_alt[];
+     int size = sizeof(unsigned int) * (end_ftr_fixup_prefix3 -
ftr_fixup_prefix3); +
+     fixup.value = fixup.mask = 8;
+     fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix3 + 1);
+     fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix3 + 4);
+     fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix3_alt);
+     fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix3_alt + 3);
+     /* Sanity check */
+     check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) == 0);
+
+     patch_feature_section(0, &fixup);
+     check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_expected, size) == 0);
+     patch_feature_section(0, &fixup);
+     check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) != 0);
+}
+#endif /* __powerpc64__ */
+
 static int __init test_feature_fixups(void)
 {
      printk(KERN_DEBUG "Running feature fixup self-tests ...\n");

@@ -701,6 +770,11 @@ static int __init test_feature_fixups(void)
      test_cpu_macros();
      test_fw_macros();
      test_lwsync_macros();
+#ifdef __powerpc64__
+     test_prefix_patching();
+     test_prefix_alt_patching();
+     test_prefix_word_alt_patching();
+#endif

      return 0;
 }