Technically the new mmapped pages are already initialized to zero
since they are anonymous, however we have to take care with the
contents that come from the remaining part of the previous page: it
may contains garbage data due to a previous heap usage (grown then
shrunken).
This patch completes commit 55f08c84. The problem could be reproduced
when emulating the build process of Perl 5.12.3 on ARMedSlack 13.37:
make[1]: Entering directory `/tmp/perl-5.12.3/cpan/Compress-Raw-Bzip2'
cc -c -I. -fno-strict-aliasing -pipe -fstack-protector \
-I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 \
-O2 -DVERSION=\"2.024\" -DXS_VERSION=\"2.024\" -fPIC "-I../.." \
-DBZ_NO_STDIO decompress.c
decompress.c: In function 'BZ2_decompress':
decompress.c:621:1: internal compiler error: Segmentation fault
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Laurent ALFONSI <laurent.alfonsi@st.com>
Signed-off-by: Cédric VINCENT <cedric.vincent@st.com>
DirectFB-1.0 uses at least two of the four added ioctls, and the two
others were added for completeness. This patch was validated with the
program "vlock -all/-new".
Signed-off-by: Cédric VINCENT <cedric.vincent@st.com>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This patch basically adapts the new semi-hosting command-line support
-- introduced by Wolfgang Schildbach in the commit 2e8785ac -- for use
in system-mode.
Note that the "arm_cmdline_len" and "host_cmdline_len" variables were
renamed respectively "input_size" and "output_size" because:
* in C, the term "length" is generally used to count the number of
character in a string, not to count the number of bytes in a
buffer (as it is the case here).
* in QEMU, the term "host" is used to name variables that are in
the host address space, not to name variables in the target
address space (as it is the case here).
* in the case of this system-call, the terms "input" and "output"
fit the semantic of the official ARM semi-hosting specification
quite well.
I know renaming can be considered harmful but I do think in this case
the semantic really matters to keep this code more understandable.
Signed-off-by: Cédric VINCENT <cedric.vincent@st.com>
Reviewed-by: Christophe Lyon <christophe.lyon@st.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Paul Brook <paul@codesourcery.com>
Cc: Wolfgang Schildbach <wschi@dolby.com>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
There were several remaining bugs in the previous implementation of
do_brk():
1. the value of "new_alloc_size" was one page too large when the
requested brk was aligned on a host page boundary.
2. no new pages should be (re-)allocated when the requested brk is
in the range of the pages that were already allocated
previsouly (for the same purpose). Technically these pages are
never unmapped in the current implementation.
The problem/fix can be reproduced/validated with the test-suite above:
#include <unistd.h> /* syscall(2), */
#include <sys/syscall.h> /* SYS_brk, */
#include <stdio.h> /* puts(3), */
#include <stdlib.h> /* exit(3), EXIT_*, */
#include <stdint.h> /* uint*_t, */
#include <sys/mman.h> /* mmap(2), MAP_*, */
#include <string.h> /* memset(3), */
int main()
{
int exit_status = EXIT_SUCCESS;
uint8_t *current_brk = 0;
uint8_t *initial_brk;
uint8_t *new_brk;
uint8_t *old_brk;
int failure = 0;
int i;
void test_brk(int increment, int expected_result) {
new_brk = (uint8_t *)syscall(SYS_brk, current_brk + increment);
if ((new_brk == current_brk) == expected_result)
failure = 1;
current_brk = (uint8_t *)syscall(SYS_brk, 0);
}
void test_result() {
if (!failure)
puts("OK");
else {
puts("failure");
exit_status = EXIT_FAILURE;
}
}
void test_title(const char *title) {
failure = 0;
printf("%-45s : ", title);
fflush(stdout);
}
test_title("Initialization");
test_brk(0, 1);
initial_brk = current_brk;
test_result();
test_title("Don't overlap \"brk\" pages");
test_brk(HOST_PAGE_SIZE, 1);
test_brk(HOST_PAGE_SIZE, 1);
test_result();
/* Preparation for the test "Re-allocated heap is initialized". */
old_brk = current_brk - HOST_PAGE_SIZE;
memset(old_brk, 0xFF, HOST_PAGE_SIZE);
test_title("Don't allocate the same \"brk\" page twice");
test_brk(-HOST_PAGE_SIZE, 1);
test_brk(HOST_PAGE_SIZE, 1);
test_result();
test_title("Re-allocated \"brk\" pages are initialized");
for (i = 0; i < HOST_PAGE_SIZE; i++) {
if (old_brk[i] != 0) {
printf("(index = %d, value = 0x%x) ", i, old_brk[i]);
failure = 1;
break;
}
}
test_result();
test_title("Don't allocate \"brk\" pages over \"mmap\" pages");
new_brk = mmap(current_brk, HOST_PAGE_SIZE / 2, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
if (new_brk == (void *) -1)
puts("unknown");
else {
test_brk(HOST_PAGE_SIZE, 0);
test_result();
}
test_title("All \"brk\" pages are writable (please wait)");
if (munmap(current_brk, HOST_PAGE_SIZE / 2) != 0)
puts("unknown");
else {
while (current_brk - initial_brk < 2*1024*1024*1024UL) {
old_brk = current_brk;
test_brk(HOST_PAGE_SIZE, -1);
if (old_brk == current_brk)
break;
for (i = 0; i < HOST_PAGE_SIZE; i++)
old_brk[i] = 0xAA;
}
puts("OK");
}
test_title("Maximum size of the heap > 16MB");
failure = (current_brk - initial_brk) < 16*1024*1024;
test_result();
exit(exit_status);
}
Changes introduced in patch v2:
* extend the "brk" test-suite embedded within the commit message;
* heap contents have to be initialized to zero, this bug was
exposed by "tst-calloc.c" from the GNU C library;
* don't [try to] allocate a new host page if the new "brk" is
equal to the latest allocated host page ("brk_page"); and
* print some debug information when DEBUGF_BRK is defined.
Signed-off-by: Cédric VINCENT <cedric.vincent@st.com>
Reviewed-by: Christophe Guillon <christophe.guillon@st.com>
Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Riku Voipio <riku.voipio@iki.fi>
This patch fixes a "double free()" due to "realloc(syms, 0)" in the
loader when the ELF file has no "useful" symbol, as with the following
example (compiled with "sh4-linux-gcc -nostdlib"):
.text
.align 1
.global _start
_start:
mov #1, r3
trapa #40 // syscall(__NR_exit)
nop
The bug appears when the log (option "-d") is enabled.
Signed-off-by: Cédric VINCENT <cedric.vincent@st.com>
Signed-off-by: Yves JANIN <yves.janin@st.com>
Signed-off-by: Riku Voipio <riku.voipio@iki.fi>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Cédric VINCENT