diff options
Diffstat (limited to 'meta/recipes-devtools/qemu/qemu/0001-linux-user-x86_64-Handle-the-vsyscall-page-in-open_s.patch')
| -rw-r--r-- | meta/recipes-devtools/qemu/qemu/0001-linux-user-x86_64-Handle-the-vsyscall-page-in-open_s.patch | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/meta/recipes-devtools/qemu/qemu/0001-linux-user-x86_64-Handle-the-vsyscall-page-in-open_s.patch b/meta/recipes-devtools/qemu/qemu/0001-linux-user-x86_64-Handle-the-vsyscall-page-in-open_s.patch new file mode 100644 index 0000000000..2eaebe883c --- /dev/null +++ b/meta/recipes-devtools/qemu/qemu/0001-linux-user-x86_64-Handle-the-vsyscall-page-in-open_s.patch @@ -0,0 +1,56 @@ +From 4517e2046610722879761bcdb60edbb2b929c848 Mon Sep 17 00:00:00 2001 +From: Richard Henderson <richard.henderson@linaro.org> +Date: Wed, 28 Feb 2024 10:25:14 -1000 +Subject: [PATCH 1/5] linux-user/x86_64: Handle the vsyscall page in + open_self_maps_{2,4} + +This is the only case in which we expect to have no host memory backing +for a guest memory page, because in general linux user processes cannot +map any pages in the top half of the 64-bit address space. + +Upstream-Status: Submitted [https://www.mail-archive.com/qemu-devel@nongnu.org/msg1026793.html] + +Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2170 +Signed-off-by: Richard Henderson <richard.henderson@linaro.org> +Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> +--- + linux-user/syscall.c | 16 ++++++++++++++++ + 1 file changed, 16 insertions(+) + +diff --git a/linux-user/syscall.c b/linux-user/syscall.c +index a114f29a8..8307a8a61 100644 +--- a/linux-user/syscall.c ++++ b/linux-user/syscall.c +@@ -7922,6 +7922,10 @@ static void open_self_maps_4(const struct open_self_maps_data *d, + path = "[heap]"; + } else if (start == info->vdso) { + path = "[vdso]"; ++#ifdef TARGET_X86_64 ++ } else if (start == TARGET_VSYSCALL_PAGE) { ++ path = "[vsyscall]"; ++#endif + } + + /* Except null device (MAP_ANON), adjust offset for this fragment. */ +@@ -8010,6 +8014,18 @@ static int open_self_maps_2(void *opaque, target_ulong guest_start, + uintptr_t host_start = (uintptr_t)g2h_untagged(guest_start); + uintptr_t host_last = (uintptr_t)g2h_untagged(guest_end - 1); + ++#ifdef TARGET_X86_64 ++ /* ++ * Because of the extremely high position of the page within the guest ++ * virtual address space, this is not backed by host memory at all. ++ * Therefore the loop below would fail. This is the only instance ++ * of not having host backing memory. ++ */ ++ if (guest_start == TARGET_VSYSCALL_PAGE) { ++ return open_self_maps_3(opaque, guest_start, guest_end, flags); ++ } ++#endif ++ + while (1) { + IntervalTreeNode *n = + interval_tree_iter_first(d->host_maps, host_start, host_start); +-- +2.34.1 + |