From 05306935b1ae49107c2dc2f301574dd6c29b6838 Mon Sep 17 00:00:00 2001 From: Fei Li Date: Tue, 25 Sep 2018 17:14:40 +0800 Subject: [PATCH] migration: fix the compression code Add judgement in compress_threads_save_cleanup() to check whether the static CompressParam *comp_param has been allocated. If not, just return; or else segmentation fault will occur when using the NULL comp_param's parameters. One test case can reproduce this is: set the compression on and migrate to a wrong nonexistent host IP address. Our current code does not judge before handling comp_param[idx]'s quit and cond that whether they have been initialized. If not initialized, "qemu_mutex_lock_impl: Assertion `mutex->initialized' failed." will occur. Fix this by squashing the terminate_compression_threads() into compress_threads_save_cleanup() and employing the existing judgement condition. One test case can reproduce this error is: set the compression on and fail to fully setup the default eight compression thread in compress_threads_save_setup(). Signed-off-by: Fei Li Message-Id: <20180925091440.18910-1-fli@suse.com> Reviewed-by: Peter Xu Signed-off-by: Dr. David Alan Gilbert --- migration/ram.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 0fdaa8efa3..408d237700 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -431,28 +431,14 @@ static void *do_data_compress(void *opaque) return NULL; } -static inline void terminate_compression_threads(void) -{ - int idx, thread_count; - - thread_count = migrate_compress_threads(); - - for (idx = 0; idx < thread_count; idx++) { - qemu_mutex_lock(&comp_param[idx].mutex); - comp_param[idx].quit = true; - qemu_cond_signal(&comp_param[idx].cond); - qemu_mutex_unlock(&comp_param[idx].mutex); - } -} - static void compress_threads_save_cleanup(void) { int i, thread_count; - if (!migrate_use_compression()) { + if (!migrate_use_compression() || !comp_param) { return; } - terminate_compression_threads(); + thread_count = migrate_compress_threads(); for (i = 0; i < thread_count; i++) { /* @@ -462,6 +448,12 @@ static void compress_threads_save_cleanup(void) if (!comp_param[i].file) { break; } + + qemu_mutex_lock(&comp_param[i].mutex); + comp_param[i].quit = true; + qemu_cond_signal(&comp_param[i].cond); + qemu_mutex_unlock(&comp_param[i].mutex); + qemu_thread_join(compress_threads + i); qemu_mutex_destroy(&comp_param[i].mutex); qemu_cond_destroy(&comp_param[i].cond); -- 2.11.4.GIT