From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34907) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ujq8S-0008Pn-KX for qemu-devel@nongnu.org; Tue, 04 Jun 2013 08:14:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Ujq8R-0002cJ-7Q for qemu-devel@nongnu.org; Tue, 04 Jun 2013 08:14:44 -0400 Received: from mail-bk0-x22d.google.com ([2a00:1450:4008:c01::22d]:44916) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ujq8R-0002cF-1c for qemu-devel@nongnu.org; Tue, 04 Jun 2013 08:14:43 -0400 Received: by mail-bk0-f45.google.com with SMTP id je10so89502bkc.32 for ; Tue, 04 Jun 2013 05:14:42 -0700 (PDT) Sender: Paolo Bonzini From: Paolo Bonzini Date: Tue, 4 Jun 2013 14:14:01 +0200 Message-Id: <1370348041-6768-18-git-send-email-pbonzini@redhat.com> In-Reply-To: <1370348041-6768-1-git-send-email-pbonzini@redhat.com> References: <1370348041-6768-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [PATCH v2 17/17] memory: ref/unref memory across address_space_map/unmap List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org The iothread mutex might be released between map and unmap, so the mapped region might disappear. Signed-off-by: Paolo Bonzini --- exec.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/exec.c b/exec.c index db03507..5c37393 100644 --- a/exec.c +++ b/exec.c @@ -2057,6 +2057,7 @@ void cpu_physical_memory_write_rom(hwaddr addr, } typedef struct { + MemoryRegion *mr; void *buffer; hwaddr addr; hwaddr len; @@ -2154,15 +2155,18 @@ void *address_space_map(AddressSpace *as, bounce.buffer = qemu_memalign(TARGET_PAGE_SIZE, TARGET_PAGE_SIZE); bounce.addr = addr; bounce.len = l; + bounce.mr = mr; if (!is_write) { address_space_read(as, addr, bounce.buffer, l); } *plen = l; + memory_region_ref(mr); return bounce.buffer; } if (!todo) { raddr = memory_region_get_ram_addr(mr) + xlat; + memory_region_ref(mr); } else { if (memory_region_get_ram_addr(mr) + xlat != raddr + todo) { memory_region_unref(mr); @@ -2189,8 +2193,12 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len, int is_write, hwaddr access_len) { if (buffer != bounce.buffer) { + MemoryRegion *mr; + ram_addr_t addr1; + + mr = qemu_ram_addr_from_host(buffer, &addr1); + assert(mr); if (is_write) { - ram_addr_t addr1 = qemu_ram_addr_from_host_nofail(buffer); while (access_len) { unsigned l; l = TARGET_PAGE_SIZE; @@ -2204,6 +2212,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len, if (xen_enabled()) { xen_invalidate_map_cache_entry(buffer); } + memory_region_unref(mr); return; } if (is_write) { @@ -2211,6 +2220,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len, } qemu_vfree(bounce.buffer); bounce.buffer = NULL; + memory_region_unref(bounce.mr); cpu_notify_map_clients(); } -- 1.8.1.4