patches/uClibc/0.9.29/100-fix-mmap.patch
author "Benoît THÉBAUDEAU" <benoit.thebaudeau@advansee.com>
Wed Jun 08 15:47:43 2011 +0200 (2011-06-08)
changeset 2508 9e2761e59a75
parent 291 64c57f736ec3
permissions -rw-r--r--
debug/cross-gdb: check host dependencies

Cross-gdb depends on expat and python. If either is missing, cross-gdb will
build successfully, but lacking some features.

Especially, if expat is missing, cross-gdb will be unable to parse the target
description, which may lead to runtime malfunctions and the following GDB
warning:
"Can not parse XML target description; XML support was disabled at compile time"

Hence, expat should be considered mandatory.

On the other hand, the features missing without python are not critical, so
python should not be considered mandatory.

This patch does the following:
- At configure time, warn the user if either expat or python is missing.
- In menuconfig, disable the static build options regarding cross-gdb if no
static version of expat is available, and disable cross-gdb if expat is
missing.

Signed-off-by: "Benoît THÉBAUDEAU" <benoit.thebaudeau@advansee.com>
[yann.morin.1998@anciens.enib.fr: add comment for impossible static cross-gdb]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
     1 --- uClibc-0.9.29.oorig/test/mmap/mmap2.c	(revision 0)
     2 +++ uClibc-0.9.29/test/mmap/mmap2.c	(revision 18616)
     3 @@ -0,0 +1,41 @@
     4 +/* When trying to map /dev/mem with offset 0xFFFFF000 on the ARM platform, mmap
     5 + * returns -EOVERFLOW.
     6 + *
     7 + * Since off_t is defined as a long int and the sign bit is set in the address,
     8 + * the shift operation shifts in ones instead of zeroes
     9 + * from the left. This results the offset sent to the kernel function becomes
    10 + * 0xFFFFFFFF instead of 0x000FFFFF with MMAP2_PAGE_SHIFT set to 12.
    11 + */
    12 +
    13 +#include <unistd.h>
    14 +#include <stdio.h>
    15 +#include <stdlib.h>
    16 +#include <string.h>
    17 +#include <errno.h>
    18 +#include <fcntl.h>
    19 +#include <sys/mman.h>
    20 +
    21 +#define FATAL do { fprintf(stderr, "Error at line %d, file %s (%d) [%s]\n", \
    22 +  __LINE__, __FILE__, errno, strerror(errno)); exit(1); } while(0)
    23 +
    24 +#define MAP_SIZE 4096UL
    25 +#define MAP_MASK (MAP_SIZE - 1)
    26 +
    27 +int main(int argc, char **argv) {
    28 +    void* map_base = 0;
    29 +    int fd;
    30 +    off_t target = 0xfffff000;
    31 +    if((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) FATAL;
    32 +    printf("/dev/mem opened.\n");
    33 +    fflush(stdout);
    34 +
    35 +   /* Map one page */
    36 +    map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED,
    37 +                        fd, target & ~MAP_MASK);
    38 +    if(map_base == (void *) -1) FATAL;
    39 +    printf("Memory mapped at address %p.\n", map_base);
    40 +    fflush(stdout);
    41 +    if(munmap(map_base, MAP_SIZE) == -1) FATAL;
    42 +    close(fd);
    43 +    return 0;
    44 +}
    45 --- uClibc-0.9.29.oorig/libc/sysdeps/linux/arm/mmap.c	(revision 18615)
    46 +++ uClibc-0.9.29/libc/sysdeps/linux/arm/mmap.c	(revision 18616)
    47 @@ -27,7 +27,6 @@ __ptr_t mmap(__ptr_t addr, size_t len, i
    48  
    49  #elif defined  (__NR_mmap2)
    50  #define __NR__mmap __NR_mmap2
    51 -
    52  #ifndef MMAP2_PAGE_SHIFT
    53  # define MMAP2_PAGE_SHIFT 12
    54  #endif
    55 @@ -39,9 +38,17 @@ __ptr_t mmap(__ptr_t addr, size_t len, i
    56  {
    57    /* check if offset is page aligned */
    58      if (offset & ((1 << MMAP2_PAGE_SHIFT) - 1))
    59 +    {
    60 +        __set_errno(EINVAL);
    61          return MAP_FAILED;
    62 +    }
    63 +#ifdef __USE_FILE_OFFSET64
    64 +  return (__ptr_t) _mmap (addr, len, prot, flags,
    65 +						  fd,((__u_quad_t) offset >> MMAP2_PAGE_SHIFT));
    66 +#else
    67    return (__ptr_t) _mmap (addr, len, prot, flags,
    68 -						  fd,(off_t) (offset >> MMAP2_PAGE_SHIFT));
    69 +                          fd,((__u_long) offset >> MMAP2_PAGE_SHIFT));
    70 +#endif
    71  }
    72  #elif defined (__NR_mmap)
    73  # define __NR__mmap __NR_mmap
    74 --- uClibc-0.9.29.oorig/libc/sysdeps/linux/common/mmap64.c	(revision 18615)
    75 +++ uClibc-0.9.29/libc/sysdeps/linux/common/mmap64.c	(revision 18616)
    76 @@ -58,8 +58,13 @@ __ptr_t mmap64(__ptr_t addr, size_t len,
    77  		__set_errno(EINVAL);
    78  		return MAP_FAILED;
    79  	}
    80 -
    81 -	return __syscall_mmap2(addr, len, prot, flags, fd, (off_t) (offset >> MMAP2_PAGE_SHIFT));
    82 +#ifdef __USE_FILE_OFFSET64
    83 +  return __syscall_mmap2(addr, len, prot, flags,
    84 +                         fd,((__u_quad_t)offset >> MMAP2_PAGE_SHIFT));
    85 +#else
    86 +   return __syscall_mmap2(addr, len, prot, flags,
    87 +                          fd,((__u_long)offset >> MMAP2_PAGE_SHIFT));
    88 +#endif
    89  }
    90  
    91  # endif