From 47281859f66bdab1974fb122cab2cbb4a1c9af7f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Mon, 21 Mar 2022 15:44:53 +0100 Subject: [PATCH] main-loop: Disable block backend global state assertion on Cocoa MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit 0439c5a462 ("block/block-backend.c: assertions for block-backend") QEMU crashes when using Cocoa on Darwin hosts. Example on macOS: $ qemu-system-i386 Assertion failed: (qemu_in_main_thread()), function blk_all_next, file block-backend.c, line 552. Abort trap: 6 Looking with lldb: Assertion failed: (qemu_in_main_thread()), function blk_all_next, file block-backend.c, line 552. Process 76914 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = hit program assert frame #4: 0x000000010057c2d4 qemu-system-i386`blk_all_next.cold.1 at block-backend.c:552:5 [opt] 549 */ 550 BlockBackend *blk_all_next(BlockBackend *blk) 551 { --> 552 GLOBAL_STATE_CODE(); 553 return blk ? QTAILQ_NEXT(blk, link) 554 : QTAILQ_FIRST(&block_backends); 555 } Target 1: (qemu-system-i386) stopped. (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = hit program assert frame #0: 0x00000001908c99b8 libsystem_kernel.dylib`__pthread_kill + 8 frame #1: 0x00000001908fceb0 libsystem_pthread.dylib`pthread_kill + 288 frame #2: 0x000000019083a314 libsystem_c.dylib`abort + 164 frame #3: 0x000000019083972c libsystem_c.dylib`__assert_rtn + 300 * frame #4: 0x000000010057c2d4 qemu-system-i386`blk_all_next.cold.1 at block-backend.c:552:5 [opt] frame #5: 0x00000001003c00b4 qemu-system-i386`blk_all_next(blk=) at block-backend.c:552:5 [opt] frame #6: 0x00000001003d8f04 qemu-system-i386`qmp_query_block(errp=0x0000000000000000) at qapi.c:591:16 [opt] frame #7: 0x000000010003ab0c qemu-system-i386`main [inlined] addRemovableDevicesMenuItems at cocoa.m:1756:21 [opt] frame #8: 0x000000010003ab04 qemu-system-i386`main(argc=, argv=) at cocoa.m:1980:5 [opt] frame #9: 0x00000001012690f4 dyld`start + 520 As we are in passed release 7.0 hard freeze, disable the block backend assertion which, while being valuable during development, is not helpful to users. We'll restore this assertion immediately once 7.0 is released and work on a fix. Suggested-by: Akihiko Odaki Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Akihiko Odaki Reviewed-by: Peter Maydell Message-Id: <20220325183707.85733-1-philippe.mathieu.daude@gmail.com> --- include/qemu/main-loop.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h index 7a4d6a0920..89bd9edefb 100644 --- a/include/qemu/main-loop.h +++ b/include/qemu/main-loop.h @@ -270,10 +270,23 @@ bool qemu_mutex_iothread_locked(void); bool qemu_in_main_thread(void); /* Mark and check that the function is part of the global state API. */ +#ifdef CONFIG_COCOA +/* + * When using the Cocoa UI, addRemovableDevicesMenuItems() is called from + * a thread different from the QEMU main thread and can not take the BQL, + * triggering this assertions in the block layer (commit 0439c5a462). + * As the Cocoa fix is not trivial, disable this assertion for the v7.0.0 + * release (when using Cocoa); we will restore it immediately after the + * release. + * This issue is tracked as https://gitlab.com/qemu-project/qemu/-/issues/926 + */ +#define GLOBAL_STATE_CODE() +#else #define GLOBAL_STATE_CODE() \ do { \ assert(qemu_in_main_thread()); \ } while (0) +#endif /* CONFIG_COCOA */ /* Mark and check that the function is part of the I/O API. */ #define IO_CODE() \