From a0ef40af1f19dfed5b852735bcdebe22554248ce Mon Sep 17 00:00:00 2001 From: Nuno Cruces Date: Wed, 26 Jun 2024 13:57:46 +0000 Subject: [PATCH] unix: fix MremapPtr test failing on NetBSD NetBSD apparently doesn't allow remapping into used address space. This means that the test that uses mremap to move a mmapped page into a new address should first mmap (to reserve) then munmap (to free) the destination. Fixes golang/go#68180 Change-Id: If66b67e7166ca4dc4331a8cfc3e3a285416e9849 GitHub-Last-Rev: 92058c2f2525be77522762d503ac7193580f125e GitHub-Pull-Request: golang/sys#198 Cq-Include-Trybots: luci.golang.try:x_sys-gotip-netbsd-amd64 Reviewed-on: https://go-review.googlesource.com/c/sys/+/594756 Reviewed-by: Ian Lance Taylor Reviewed-by: Joedian Reid Auto-Submit: Dmitri Shuralyov LUCI-TryBot-Result: Go LUCI --- unix/mremap_test.go | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/unix/mremap_test.go b/unix/mremap_test.go index 5019dd789..fe79a4886 100644 --- a/unix/mremap_test.go +++ b/unix/mremap_test.go @@ -47,30 +47,31 @@ func TestMremap(t *testing.T) { } func TestMremapPtr(t *testing.T) { - mmapProt := unix.PROT_NONE - mmapPtrProt := unix.PROT_READ | unix.PROT_WRITE - b, err := unix.Mmap(-1, 0, 2*unix.Getpagesize(), mmapProt, unix.MAP_ANON|unix.MAP_PRIVATE) + p1, err := unix.MmapPtr(-1, 0, nil, uintptr(2*unix.Getpagesize()), + unix.PROT_READ|unix.PROT_WRITE, unix.MAP_ANON|unix.MAP_PRIVATE) if err != nil { - t.Fatalf("Mmap: %v", err) - } - if _, err := unix.MmapPtr(-1, 0, unsafe.Pointer(&b[0]), uintptr(unix.Getpagesize()), - mmapPtrProt, unix.MAP_ANON|unix.MAP_PRIVATE|unix.MAP_FIXED); err != nil { t.Fatalf("MmapPtr: %v", err) } - b[0] = 42 + p2 := unsafe.Add(p1, unix.Getpagesize()) + if err := unix.MunmapPtr(p2, uintptr(unix.Getpagesize())); err != nil { + t.Fatalf("MunmapPtr: %v", err) + } + + *(*byte)(p1) = 42 if _, err := unix.MremapPtr( - unsafe.Pointer(&b[0]), uintptr(unix.Getpagesize()), - unsafe.Pointer(&b[unix.Getpagesize()]), uintptr(unix.Getpagesize()), + p1, uintptr(unix.Getpagesize()), + p2, uintptr(unix.Getpagesize()), unix.MremapFixed|unix.MremapMaymove); err != nil { t.Fatalf("MremapPtr: %v", err) } - if got := b[unix.Getpagesize()]; got != 42 { + + if got := *(*byte)(p2); got != 42 { t.Errorf("got %d, want 42", got) } - if err := unix.Munmap(b); err != nil { - t.Fatalf("Munmap: %v", err) + if err := unix.MunmapPtr(p2, uintptr(unix.Getpagesize())); err != nil { + t.Fatalf("MunmapPtr: %v", err) } }