Re: [PATCH] Fix i386 memmove issue [BZ #22644]

[Andrew Senkevich <andrew.n.senkevich@gmail.com>]

2018-03-19 20:38 GMT+01:00 H.J. Lu <hjl.tools@gmail.com>:
> On Mon, Mar 19, 2018 at 12:29 PM, Andrew Senkevich
> <andrew.n.senkevich@gmail.com> wrote:
>> 2018-03-19 18:57 GMT+01:00 H.J. Lu <hjl.tools@gmail.com>:
>>> On Mon, Mar 19, 2018 at 10:52 AM, Andrew Senkevich
>>> <andrew.n.senkevich@gmail.com> wrote:
>>>> 2018-03-19 16:33 GMT+01:00 Florian Weimer <fweimer@redhat.com>:
>>>>> On 03/19/2018 03:25 PM, Szabolcs Nagy wrote:
>>>>>>
>>>>>> i thought not using MAP_FIXED is the 'non-overriding MAP_FIXED variant'
>>>>
>>>> Hmm, I tried so and had got much bigger address. But now I see it
>>>> works (with size just 0x20000000 and 0x70000000 as a hint) in both 64
>>>> and 32 bit cases, so proposing the following:
>>>>
>>>> diff --git a/string/test-memmove.c b/string/test-memmove.c
>>>> index edc7a4c..fa4037d 100644
>>>> --- a/string/test-memmove.c
>>>> +++ b/string/test-memmove.c
>>>> @@ -24,6 +24,7 @@
>>>>  # define TEST_NAME "memmove"
>>>>  #endif
>>>>  #include "test-string.h"
>>>> +#include <support/test-driver.h>
>>>>
>>>>  char *simple_memmove (char *, const char *, size_t);
>>>>
>>>> @@ -245,6 +246,59 @@ do_random_tests (void)
>>>>      }
>>>>  }
>>>>
>>>> +static void
>>>> +do_test2 (void)
>>>> +{
>>>> +  size_t size = 0x20000000;
>>>> +  uint32_t * large_buf;
>>>> +
>>>> +  large_buf = mmap ((void*)0x70000000, size, PROT_READ | PROT_WRITE,
>>>> +     MAP_PRIVATE | MAP_ANON, -1, 0);
>>>> +
>>>> +  if (large_buf == MAP_FAILED)
>>>> +    error (EXIT_UNSUPPORTED, errno, "Large mmap failed");
>>>> +
>>>> +  if ((uintptr_t)large_buf > 0x80000000 - 128)
>>>
>>> Don't you need to test if address is too low such that
>>> 0x80000000 - (uintptr_t)large_buf > 0x20000000?
>>
>> Indeed, thanks. Updated below.
>>
>> diff --git a/string/test-memmove.c b/string/test-memmove.c
>> index edc7a4c..9f1437d 100644
>> --- a/string/test-memmove.c
>> +++ b/string/test-memmove.c
>> @@ -24,6 +24,7 @@
>>  # define TEST_NAME "memmove"
>>  #endif
>>  #include "test-string.h"
>> +#include <support/test-driver.h>
>>
>>  char *simple_memmove (char *, const char *, size_t);
>>
>> @@ -245,6 +246,60 @@ do_random_tests (void)
>>      }
>>  }
>>
>> +static void
>> +do_test2 (void)
>> +{
>> +  size_t size = 0x20000000;
>> +  uint32_t * large_buf;
>> +
>> +  large_buf = mmap ((void*)0x70000000, size, PROT_READ | PROT_WRITE,
>> +     MAP_PRIVATE | MAP_ANON, -1, 0);
>> +
>> +  if (large_buf == MAP_FAILED)
>> +    error (EXIT_UNSUPPORTED, errno, "Large mmap failed");
>> +
>> +  if ((uintptr_t)large_buf > 0x80000000 - 128
>> +      || 0x80000000 - (uintptr_t)large_buf > 0x20000000)
>> +    {
>> +      error (0, 0,"Large mmap allocated improperly");
>> +      ret = EXIT_UNSUPPORTED;
>> +      munmap((void *)large_buf, size);
>> +      return;
>> +    }
>> +
>> +  size_t bytes_move = 0x80000000 - (uintptr_t)large_buf;
>> +  size_t arr_size = bytes_move / sizeof(uint32_t);
>> +  size_t i;
>> +
>> +  FOR_EACH_IMPL (impl, 0)
>> +    {
>> +      for (i = 0; i < arr_size; i++)
>> +        large_buf[i] = i;
>> +
>> +      uint32_t * dst = &large_buf[33];
>> +
>> +#ifdef TEST_BCOPY
>> +      CALL (impl, (char *)large_buf, (char *)dst, bytes_move);
>> +#else
>> +      CALL (impl, (char *)dst, (char *)large_buf, bytes_move);
>> +#endif
>> +
>> +      for (i = 0; i < arr_size; i++)
>> +        {
>> +          if (dst[i] != i)
>> +     {
>> +       error (0, 0,
>> +      "Wrong result in function %s dst \"%p\" src \"%p\" offset \"%d\"",
>> +      impl->name, dst, large_buf, i);
>> +       ret = 1;
>> +       break;
>> +     }
>> + }
>> +    }
>> +
>> +  munmap((void *)large_buf, size);
>> +}
>> +
>>  int
>>  test_main (void)
>>  {
>> @@ -284,6 +339,9 @@ test_main (void)
>>      }
>>
>>    do_random_tests ();
>> +
>> +  do_test2 ();
>> +
>>    return ret;
>>  }
>>
>>
>
> Look good.
>
> Please submit the updated patch with the proper commit message.

[BZ #22644] Fix i386 memmove issue.

        * sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S: Fixed
        branch conditions.
        * string/test-memmove.c (do_test2): New testcase.

diff --git a/ChangeLog b/ChangeLog
index 4eb0632..5a0e335 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2018-03-19  Andrew Senkevich  <andrew.senkevich@intel.com>
+     Max Horn <max@quendi.de>
+
+ [BZ #22644]
+ * sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S: Fixed
+ branch conditions.
+ * string/test-memmove.c (do_test2): New testcase.
+
 2018-03-19  Wilco Dijkstra  <wdijkstr@arm.com>

  * benchtests/bench-timing.h (attribute_hidden): Undefine.
diff --git a/string/test-memmove.c b/string/test-memmove.c
index edc7a4c..9f1437d 100644
--- a/string/test-memmove.c
+++ b/string/test-memmove.c
@@ -24,6 +24,7 @@
 # define TEST_NAME "memmove"
 #endif
 #include "test-string.h"
+#include <support/test-driver.h>

 char *simple_memmove (char *, const char *, size_t);

@@ -245,6 +246,60 @@ do_random_tests (void)
     }
 }

+static void
+do_test2 (void)
+{
+  size_t size = 0x20000000;
+  uint32_t * large_buf;
+
+  large_buf = mmap ((void*)0x70000000, size, PROT_READ | PROT_WRITE,
+     MAP_PRIVATE | MAP_ANON, -1, 0);
+
+  if (large_buf == MAP_FAILED)
+    error (EXIT_UNSUPPORTED, errno, "Large mmap failed");
+
+  if ((uintptr_t)large_buf > 0x80000000 - 128
+      || 0x80000000 - (uintptr_t)large_buf > 0x20000000)
+    {
+      error (0, 0,"Large mmap allocated improperly");
+      ret = EXIT_UNSUPPORTED;
+      munmap((void *)large_buf, size);
+      return;
+    }
+
+  size_t bytes_move = 0x80000000 - (uintptr_t)large_buf;
+  size_t arr_size = bytes_move / sizeof(uint32_t);
+  size_t i;
+
+  FOR_EACH_IMPL (impl, 0)
+    {
+      for (i = 0; i < arr_size; i++)
+        large_buf[i] = i;
+
+      uint32_t * dst = &large_buf[33];
+
+#ifdef TEST_BCOPY
+      CALL (impl, (char *)large_buf, (char *)dst, bytes_move);
+#else
+      CALL (impl, (char *)dst, (char *)large_buf, bytes_move);
+#endif
+
+      for (i = 0; i < arr_size; i++)
+        {
+          if (dst[i] != i)
+     {
+       error (0, 0,
+      "Wrong result in function %s dst \"%p\" src \"%p\" offset \"%d\"",
+      impl->name, dst, large_buf, i);
+       ret = 1;
+       break;
+     }
+ }
+    }
+
+  munmap((void *)large_buf, size);
+}
+
 int
 test_main (void)
 {
@@ -284,6 +339,9 @@ test_main (void)
     }

   do_random_tests ();
+
+  do_test2 ();
+
   return ret;
 }

diff --git a/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
b/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
index 9c3bbe7..9aa17de 100644
--- a/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
+++ b/sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S
@@ -72,7 +72,7 @@ ENTRY (MEMCPY)
  cmp %edx, %eax

 # ifdef USE_AS_MEMMOVE
- jg L(check_forward)
+ ja L(check_forward)

 L(mm_len_0_or_more_backward):
 /* Now do checks for lengths. We do [0..16], [16..32], [32..64], [64..128]
@@ -81,7 +81,7 @@ L(mm_len_0_or_more_backward):
  jbe L(mm_len_0_16_bytes_backward)

  cmpl $32, %ecx
- jg L(mm_len_32_or_more_backward)
+ ja L(mm_len_32_or_more_backward)

 /* Copy [0..32] and return.  */
  movdqu (%eax), %xmm0
@@ -92,7 +92,7 @@ L(mm_len_0_or_more_backward):

 L(mm_len_32_or_more_backward):
  cmpl $64, %ecx
- jg L(mm_len_64_or_more_backward)
+ ja L(mm_len_64_or_more_backward)

 /* Copy [0..64] and return.  */
  movdqu (%eax), %xmm0
@@ -107,7 +107,7 @@ L(mm_len_32_or_more_backward):

 L(mm_len_64_or_more_backward):
  cmpl $128, %ecx
- jg L(mm_len_128_or_more_backward)
+ ja L(mm_len_128_or_more_backward)

 /* Copy [0..128] and return.  */
  movdqu (%eax), %xmm0
@@ -132,7 +132,7 @@ L(mm_len_128_or_more_backward):
  add %ecx, %eax
  cmp %edx, %eax
  movl SRC(%esp), %eax
- jle L(forward)
+ jbe L(forward)
  PUSH (%esi)
  PUSH (%edi)
  PUSH (%ebx)
@@ -269,7 +269,7 @@ L(check_forward):
  add %edx, %ecx
  cmp %eax, %ecx
  movl LEN(%esp), %ecx
- jle L(forward)
+ jbe L(forward)

 /* Now do checks for lengths. We do [0..16], [0..32], [0..64], [0..128]
  separately.  */


--
WBR,
Andrew