On 1/2/24 05:57, Richard Henderson wrote:
If reserved_va, then we have already reserved the entire
guest virtual address space; no need to remap page.
If !reserved_va, then use MAP_FIXED_NOREPLACE.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/elfload.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index c166faabab..96d8d4f84c 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1969,16 +1969,21 @@ static inline void init_thread(struct target_pt_regs
*regs,
static bool init_guest_commpage(void)
{
- void *want = g2h_untagged(LO_COMMPAGE);
- void *addr = mmap(want, qemu_host_page_size, PROT_NONE,
- MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0);
+ /* If reserved_va, then we have already mapped 0 page on the host. */
+ if (!reserved_va) {
+ int host_page_size = qemu_real_host_page_size();
+ void *want, *addr;
- if (addr == MAP_FAILED) {
- perror("Allocating guest commpage");
- exit(EXIT_FAILURE);
- }
- if (addr != want) {
- return false;
+ want = g2h_untagged(LO_COMMPAGE);
+ addr = mmap(want, host_page_size, PROT_NONE,
+ MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED_NOREPLACE, -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("Allocating guest commpage");
+ exit(EXIT_FAILURE);
+ }
+ if (addr != want) {
+ return false;
+ }
}
/*
Reviewed-by: Pierrick Bouvier <pierrick.bouv...@linaro.org>
