From becb1a6e9deabad529c8bc1c90eb7d947505695b Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Thu, 11 Dec 2014 10:44:41 +0100 Subject: [PATCH] bus: fix memfd-cache regarding memfd offsets We must restore part->mmap_begin when poping memfds from the memfd-cache. We rely on the memfds to be unsealed, so we can be sure that we own the whole FD. Therefore, simply set part->mmap_begin to the same as part->data. This fixes test-bus-kernel-benchmark. --- src/libsystemd/sd-bus/bus-message.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c index 06d8d770f..0803999e0 100644 --- a/src/libsystemd/sd-bus/bus-message.c +++ b/src/libsystemd/sd-bus/bus-message.c @@ -65,9 +65,11 @@ static void message_free_part(sd_bus_message *m, struct bus_body_part *part) { /* If we can reuse the memfd, try that. For that it * can't be sealed yet. */ - if (!part->sealed) + if (!part->sealed) { + assert(part->memfd_offset == 0); + assert(part->data == part->mmap_begin); bus_kernel_push_memfd(m->bus, part->memfd, part->data, part->mapped, part->allocated); - else { + } else { if (part->mapped > 0) assert_se(munmap(part->mmap_begin, part->mapped) == 0); @@ -1103,8 +1105,10 @@ static int part_make_space( if (m->poisoned) return -ENOMEM; - if (!part->data && part->memfd < 0) + if (!part->data && part->memfd < 0) { part->memfd = bus_kernel_pop_memfd(m->bus, &part->data, &part->mapped, &part->allocated); + part->mmap_begin = part->data; + } if (part->memfd >= 0) { -- 2.30.2