[PATCH v4 3/4] linux-user: Populate vdso_sigreturn_region_{start, end} from sigtramp page

[Richard Henderson <richard.henderson@linaro.org>]

When a target does not support a vdso, we generate a sigtramp page.
The only thing on this page is a (set of) signal return syscalls.
We do not need to narrowly restrict the vdso_sigreturn_region;
simply record the entire page for all such targets.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/elfload.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 28f0909d1a..1370ec59be 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1974,6 +1974,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
 
         setup_sigtramp(tramp_page);
         target_mprotect(tramp_page, TARGET_PAGE_SIZE, PROT_READ | PROT_EXEC);
+        vdso_sigreturn_region_start = tramp_page;
+        vdso_sigreturn_region_end = tramp_page + TARGET_PAGE_SIZE;
     }
 
     bprm->p = create_elf_tables(bprm->p, bprm->argc, bprm->envc, &ehdr, info,
-- 
2.43.0