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Fix last page errors in page_check_range and page_set_flags. 

The addr < end comparison prevents iterating over the last
page in the guest address space; an iteration based on
length avoids this problem.

At the same time, assert that the given address is in the
guest address space.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2010-03-10 15:57:04 -08:00 committed by Paul Brook
parent 5cd2c5b6ad
commit 376a790970
1 changed files with 36 additions and 18 deletions
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54
exec.c
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@ -2315,27 +2315,35 @@ int page_get_flags(target_ulong address)
return p->flags;
}
/* modify the flags of a page and invalidate the code if
necessary. The flag PAGE_WRITE_ORG is positioned automatically
depending on PAGE_WRITE */
/* Modify the flags of a page and invalidate the code if necessary.
The flag PAGE_WRITE_ORG is positioned automatically depending
on PAGE_WRITE. The mmap_lock should already be held. */
void page_set_flags(target_ulong start, target_ulong end, int flags)
{
PageDesc *p;
target_ulong addr;
target_ulong addr, len;
/* This function should never be called with addresses outside the
guest address space. If this assert fires, it probably indicates
a missing call to h2g_valid. */
#if HOST_LONG_BITS > L1_MAP_ADDR_SPACE_BITS
assert(end < (1ul << L1_MAP_ADDR_SPACE_BITS));
#endif
assert(start < end);
/* mmap_lock should already be held. */
start = start & TARGET_PAGE_MASK;
end = TARGET_PAGE_ALIGN(end);
if (flags & PAGE_WRITE)
if (flags & PAGE_WRITE) {
flags |= PAGE_WRITE_ORG;
for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) {
p = page_find_alloc(addr >> TARGET_PAGE_BITS);
/* We may be called for host regions that are outside guest
address space. */
if (!p)
return;
/* if the write protection is set, then we invalidate the code
inside */
}
for (addr = start, len = end - start;
len != 0;
len -= TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
PageDesc *p = page_find_alloc(addr >> TARGET_PAGE_BITS, 1);
/* If the write protection bit is set, then we invalidate
the code inside. */
if (!(p->flags & PAGE_WRITE) &&
(flags & PAGE_WRITE) &&
p->first_tb) {
@ -2351,14 +2359,24 @@ int page_check_range(target_ulong start, target_ulong len, int flags)
target_ulong end;
target_ulong addr;
if (start + len < start)
/* we've wrapped around */
/* This function should never be called with addresses outside the
guest address space. If this assert fires, it probably indicates
a missing call to h2g_valid. */
#if HOST_LONG_BITS > L1_MAP_ADDR_SPACE_BITS
assert(start < (1ul << L1_MAP_ADDR_SPACE_BITS));
#endif
if (start + len - 1 < start) {
/* We've wrapped around. */
return -1;
}
end = TARGET_PAGE_ALIGN(start+len); /* must do before we loose bits in the next step */
start = start & TARGET_PAGE_MASK;
for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) {
for (addr = start, len = end - start;
len != 0;
len -= TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
p = page_find(addr >> TARGET_PAGE_BITS);
if( !p )
return -1;