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> Reviewed-by: Pierrick Bouvier <pierrick.bouv...@linaro.org> Reviewed-by: Ilya Leoshkevich <i...@linux.ibm.com> Acked-by: Helge Deller <del...@gmx.de> Message-Id: <20240102015808.132373-6-richard.hender...@linaro.org> --- linux-user/elfload.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/linux-user/elfload.c b/linux-user/elfload.c index dfb152bfcb..1893b3c192 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -1970,16 +1970,20 @@ 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) { + 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, TARGET_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; + } } /* -- 2.34.1