From e6af1e085416378918cca357bf2abd8b90224667 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Sat, 5 Nov 2016 00:03:15 +0100 Subject: [PATCH 1/3] block: Don't mark node clean after failed flush Commit 3ff2f67a changed bdrv_co_flush() so that no flush is issues if the image hasn't been dirtied since the last flush. This is not quite correct: The condition should be that the image hasn't been dirtied since the last _successful_ flush. This patch changes the logic accordingly. Without this fix, subsequent bdrv_co_flush() calls would return success without actually doing anything even though the image is still dirty. The difference is visible in some blkdebug test cases where error messages incorrectly disappeared after commit 3ff2f67a. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf Reviewed-by: Denis V. Lunev Reviewed-by: Stefan Hajnoczi Reviewed-by: John Snow Message-id: 1478300595-10090-1-git-send-email-kwolf@redhat.com Signed-off-by: Stefan Hajnoczi --- block/io.c | 4 +++- tests/qemu-iotests/026.out | 22 ++++++++++++++++++++++ tests/qemu-iotests/026.out.nocache | 22 ++++++++++++++++++++++ tests/qemu-iotests/071.out | 2 ++ 4 files changed, 49 insertions(+), 1 deletion(-) diff --git a/block/io.c b/block/io.c index 37749b680a..aa532a5c1f 100644 --- a/block/io.c +++ b/block/io.c @@ -2372,7 +2372,9 @@ flush_parent: ret = bs->file ? bdrv_co_flush(bs->file->bs) : 0; out: /* Notify any pending flushes that we have completed */ - bs->flushed_gen = current_gen; + if (ret == 0) { + bs->flushed_gen = current_gen; + } bs->active_flush_req = false; /* Return value is ignored - it's ok if wait queue is empty */ qemu_co_queue_next(&bs->flush_queue); diff --git a/tests/qemu-iotests/026.out b/tests/qemu-iotests/026.out index 853173572b..59b8f74cd4 100644 --- a/tests/qemu-iotests/026.out +++ b/tests/qemu-iotests/026.out @@ -14,6 +14,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error @@ -22,6 +23,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error @@ -40,6 +42,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -48,6 +51,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -286,12 +290,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -308,12 +314,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -330,12 +338,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -352,12 +362,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -374,12 +386,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -396,12 +410,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -513,6 +529,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_blocks; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -521,6 +538,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_blocks; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -539,6 +557,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_table; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -547,6 +566,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_table; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -611,6 +631,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_grow_write_table; errno: 5; imm: off; once: off +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -622,6 +643,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_grow_write_table; errno: 28; imm: off; once: off +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. diff --git a/tests/qemu-iotests/026.out.nocache b/tests/qemu-iotests/026.out.nocache index 672d77c6ec..b4aeebcc61 100644 --- a/tests/qemu-iotests/026.out.nocache +++ b/tests/qemu-iotests/026.out.nocache @@ -14,6 +14,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error @@ -22,6 +23,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error @@ -40,6 +42,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -48,6 +51,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_update; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -294,12 +298,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -316,12 +322,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_load; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -338,12 +346,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -360,12 +370,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_update_part; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -382,12 +394,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 5; imm: off; once: off; write +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 5; imm: off; once: off; write -b +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -404,12 +418,14 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. @@ -521,6 +537,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_blocks; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -529,6 +546,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_blocks; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -547,6 +565,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_table; errno: 28; imm: off; once: off; write +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -555,6 +574,7 @@ This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc_write_table; errno: 28; imm: off; once: off; write -b +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device @@ -619,6 +639,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_grow_write_table; errno: 5; imm: off; once: off +Failed to flush the L2 table cache: Input/output error Failed to flush the refcount block cache: Input/output error write failed: Input/output error No errors were found on the image. @@ -630,6 +651,7 @@ No errors were found on the image. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: l1_grow_write_table; errno: 28; imm: off; once: off +Failed to flush the L2 table cache: No space left on device Failed to flush the refcount block cache: No space left on device write failed: No space left on device No errors were found on the image. diff --git a/tests/qemu-iotests/071.out b/tests/qemu-iotests/071.out index 8c6851e792..8ff423f56b 100644 --- a/tests/qemu-iotests/071.out +++ b/tests/qemu-iotests/071.out @@ -86,5 +86,7 @@ read failed: Input/output error {"return": ""} {"return": {}} {"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN"} +QEMU_PROG: Failed to flush the L2 table cache: Input/output error +QEMU_PROG: Failed to flush the refcount block cache: Input/output error *** done From 36173ec5f1d3baee62504affd761199693c14c82 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 8 Nov 2016 14:55:23 +0100 Subject: [PATCH 2/3] aio-posix: avoid NULL pointer dereference in aio_epoll_update aio_epoll_update dereferences parameter "node", but it could have been NULL if deleting an fd handler that was not registered in the first place. Signed-off-by: Paolo Bonzini Reviewed-by: Fam Zheng Message-id: 20161108135524.25927-2-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi --- aio-posix.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) diff --git a/aio-posix.c b/aio-posix.c index 4ef34dd175..304b0168ff 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -217,21 +217,23 @@ void aio_set_fd_handler(AioContext *ctx, /* Are we deleting the fd handler? */ if (!io_read && !io_write) { - if (node) { - g_source_remove_poll(&ctx->source, &node->pfd); + if (node == NULL) { + return; + } - /* If the lock is held, just mark the node as deleted */ - if (ctx->walking_handlers) { - node->deleted = 1; - node->pfd.revents = 0; - } else { - /* Otherwise, delete it for real. We can't just mark it as - * deleted because deleted nodes are only cleaned up after - * releasing the walking_handlers lock. - */ - QLIST_REMOVE(node, node); - deleted = true; - } + g_source_remove_poll(&ctx->source, &node->pfd); + + /* If the lock is held, just mark the node as deleted */ + if (ctx->walking_handlers) { + node->deleted = 1; + node->pfd.revents = 0; + } else { + /* Otherwise, delete it for real. We can't just mark it as + * deleted because deleted nodes are only cleaned up after + * releasing the walking_handlers lock. + */ + QLIST_REMOVE(node, node); + deleted = true; } } else { if (node == NULL) { From 35dd66e23ce96283723de58e10d2877ae2be4a1b Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 8 Nov 2016 14:55:24 +0100 Subject: [PATCH 3/3] aio-posix: simplify aio_epoll_update Extract common code out of the "if". Reviewed-by: Fam Zheng Signed-off-by: Paolo Bonzini Message-id: 20161108135524.25927-3-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi --- aio-posix.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/aio-posix.c b/aio-posix.c index 304b0168ff..e13b9ab2b0 100644 --- a/aio-posix.c +++ b/aio-posix.c @@ -81,29 +81,22 @@ static void aio_epoll_update(AioContext *ctx, AioHandler *node, bool is_new) { struct epoll_event event; int r; + int ctl; if (!ctx->epoll_enabled) { return; } if (!node->pfd.events) { - r = epoll_ctl(ctx->epollfd, EPOLL_CTL_DEL, node->pfd.fd, &event); - if (r) { - aio_epoll_disable(ctx); - } + ctl = EPOLL_CTL_DEL; } else { event.data.ptr = node; event.events = epoll_events_from_pfd(node->pfd.events); - if (is_new) { - r = epoll_ctl(ctx->epollfd, EPOLL_CTL_ADD, node->pfd.fd, &event); - if (r) { - aio_epoll_disable(ctx); - } - } else { - r = epoll_ctl(ctx->epollfd, EPOLL_CTL_MOD, node->pfd.fd, &event); - if (r) { - aio_epoll_disable(ctx); - } - } + ctl = is_new ? EPOLL_CTL_ADD : EPOLL_CTL_MOD; + } + + r = epoll_ctl(ctx->epollfd, ctl, node->pfd.fd, &event); + if (r) { + aio_epoll_disable(ctx); } }