From: Warner Losh <imp@bsdimp.com>
To: qemu-devel@nongnu.org
Cc: Kyle Evans <kevans@FreeBSD.org>,
richard.henderson@linaro.org, f4bug@amsat.org,
Warner Losh <imp@bsdimp.com>
Subject: [PATCH v2 8/9] bsd-user/mmap.c: Implement MAP_EXCL, required by jemalloc in head
Date: Tue, 21 Sep 2021 22:56:35 -0600 [thread overview]
Message-ID: <20210922045636.25206-9-imp@bsdimp.com> (raw)
In-Reply-To: <20210922045636.25206-1-imp@bsdimp.com>
From: Kyle Evans <kevans@FreeBSD.org>
jemalloc requires a working MAP_EXCL. Ensure that no page is double
mapped when specified.
Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
Signed-off-by: Warner Losh <imp@bsdimp.com>
---
bsd-user/mmap.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/bsd-user/mmap.c b/bsd-user/mmap.c
index 347d314aa9..792ff00548 100644
--- a/bsd-user/mmap.c
+++ b/bsd-user/mmap.c
@@ -387,7 +387,7 @@ abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
int flags, int fd, off_t offset)
{
- abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
+ abi_ulong addr, ret, end, real_start, real_end, retaddr, host_offset, host_len;
mmap_lock();
#ifdef DEBUG_MMAP
@@ -599,6 +599,14 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
goto the_end;
}
+ /* Reject the mapping if any page within the range is mapped */
+ if (flags & MAP_EXCL) {
+ for (addr = start; addr < end; addr++) {
+ if (page_get_flags(addr) != 0)
+ goto fail;
+ }
+ }
+
/* handle the start of the mapping */
if (start > real_start) {
if (real_end == real_start + qemu_host_page_size) {
--
2.32.0
next prev parent reply other threads:[~2021-09-22 5:05 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-22 4:56 [PATCH v2 0/9] bsd-user mmap fixes Warner Losh
2021-09-22 4:56 ` [PATCH v2 1/9] bsd-user/mmap.c: Always zero MAP_ANONYMOUS memory in mmap_frag() Warner Losh
2021-09-23 17:35 ` Richard Henderson
2021-09-22 4:56 ` [PATCH v2 2/9] bsd-user/mmap.c: check pread's return value to fix warnings with _FORTIFY_SOURCE Warner Losh
2021-09-23 17:36 ` Richard Henderson
2021-09-24 15:07 ` Warner Losh
2021-09-25 10:54 ` Philippe Mathieu-Daudé
2021-09-22 4:56 ` [PATCH v2 3/9] bsd-user/mmap.c: MAP_ symbols are defined, so no need for ifdefs Warner Losh
2021-09-23 17:37 ` Richard Henderson
2021-09-22 4:56 ` [PATCH v2 4/9] bsd-user/mmap.c: mmap return ENOMEM on overflow Warner Losh
2021-09-23 17:38 ` Richard Henderson
2021-09-25 10:55 ` Philippe Mathieu-Daudé
2021-09-22 4:56 ` [PATCH v2 5/9] bsd-user/mmap.c: mmap prefer MAP_ANON for BSD Warner Losh
2021-09-23 17:38 ` Richard Henderson
2021-09-22 4:56 ` [PATCH v2 6/9] bsd-user/mmap.c: line wrap change Warner Losh
2021-09-23 17:41 ` Richard Henderson
2021-09-26 16:46 ` Warner Losh
2021-09-22 4:56 ` [PATCH v2 7/9] bsd-user/mmap.c: Don't mmap fd == -1 independently from MAP_ANON flag Warner Losh
2021-09-23 17:43 ` Richard Henderson
2021-09-26 17:08 ` Warner Losh
2021-09-26 19:07 ` Guy Yur
2021-09-27 0:17 ` Warner Losh
2021-09-22 4:56 ` Warner Losh [this message]
2021-09-23 17:52 ` [PATCH v2 8/9] bsd-user/mmap.c: Implement MAP_EXCL, required by jemalloc in head Richard Henderson
2021-09-26 18:38 ` Warner Losh
2021-09-22 4:56 ` [PATCH v2 9/9] bsd-user/mmap.c: assert that target_mprotect cannot fail Warner Losh
2021-09-23 17:53 ` Richard Henderson
2021-09-25 10:58 ` Philippe Mathieu-Daudé
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