From b6212bb17ce42aaf90324394dd63d8e82de80b95c9a569df503134947113a25b Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Mon, 22 Mar 2021 21:05:28 +0000 Subject: [PATCH] Accepting request 879542 from home:hmzhao:branches:openSUSE:Factory - cluster-md/mdadm : avoid useless re-sync (bsc#1181341) 0114-super1-fix-Floating-point-exception.patch 0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch OBS-URL: https://build.opensuse.org/request/show/879542 OBS-URL: https://build.opensuse.org/package/show/Base:System/mdadm?expand=0&rev=195 --- ...-super1-fix-Floating-point-exception.patch | 41 +++++++++++++ ...seless-sync-when-bitmap-switches-fro.patch | 57 +++++++++++++++++++ mdadm.changes | 7 +++ mdadm.spec | 4 ++ 4 files changed, 109 insertions(+) create mode 100644 0114-super1-fix-Floating-point-exception.patch create mode 100644 0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch diff --git a/0114-super1-fix-Floating-point-exception.patch b/0114-super1-fix-Floating-point-exception.patch new file mode 100644 index 0000000..dd2ab12 --- /dev/null +++ b/0114-super1-fix-Floating-point-exception.patch @@ -0,0 +1,41 @@ +From e6561c4defe853eaa6be27da0bb6bbd36e197b1f Mon Sep 17 00:00:00 2001 +From: Zhao Heming +Date: Sat, 30 Jan 2021 17:49:54 +0800 +Subject: [PATCH 1/2] super1: fix Floating point exception + +write_bitmap1 didn't check return value of locate_bitmap1, which will +operate bitmap area under invalid bitmap info. + +mdadm core dumped when doing below steps: +``` +node1 # mdadm -C /dev/md0 -b none -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb +node1 # mdadm -Ss +node1 # mdadm -A -U home-cluster --home-cluster=abc /dev/md0 /dev/sda /dev/sdb +Floating point exception (core dumped) +``` + +Signed-off-by: Zhao Heming +Signed-off-by: Jes Sorensen +--- + super1.c | 5 ++++- + 1 file changed, 4 insertions(+), 1 deletion(-) + +diff --git a/super1.c b/super1.c +index 7bee02659b18..70aa1d3d0219 100644 +--- a/super1.c ++++ b/super1.c +@@ -2717,7 +2717,10 @@ static int write_bitmap1(struct supertype *st, int fd, enum bitmap_update update + + init_afd(&afd, fd); + +- locate_bitmap1(st, fd, 0); ++ if (locate_bitmap1(st, fd, 0) < 0) { ++ pr_err("Error: Invalid bitmap\n"); ++ return -EINVAL; ++ } + + if (posix_memalign(&buf, 4096, 4096)) + return -ENOMEM; +-- +1.8.3.1 + diff --git a/0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch b/0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch new file mode 100644 index 0000000..dff3218 --- /dev/null +++ b/0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch @@ -0,0 +1,57 @@ +From f7a6246bab1541d7208a5f0f9f0c6cac114e38da Mon Sep 17 00:00:00 2001 +From: Zhao Heming +Date: Wed, 3 Feb 2021 08:22:51 +0800 +Subject: [PATCH 2/2] super1.c: avoid useless sync when bitmap switches from + clustered to none + +With kernel commit 480523feae58 ("md: only call set_in_sync() when it +is expected to succeed."), mddev->in_sync in clustered array is always +zero. It makes metadata resync_offset to always zero. +When assembling a clusterd array with "-U no-bitmap" option, kernel +md layer "mddev->resync_offset == 0" and "mddev->bitmap == NULL" will +trigger raid1 do sync on every bitmap chunk. the sync action is useless, +we should avoid it. + +Related kernel flow: +``` +md_do_sync + mddev->pers->sync_request + raid1_sync_request + md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) + __bitmap_start_sync(bitmap, offset,&blocks1, degraded) + if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */ + *blocks = 1024; + return 1; /* always resync if no bitmap */ + } +``` + +Reprodusible steps: +``` +node1 # mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sd{a,b} +node1 # mdadm -Ss +(in another shell, executing & watching: watch -n 1 'cat /proc/mdstat') +node1 # mdadm -A -U no-bitmap /dev/md0 /dev/sd{a,b} +``` + +Signed-off-by: Zhao Heming +Signed-off-by: Jes Sorensen +--- + super1.c | 2 ++ + 1 file changed, 2 insertions(+) + +diff --git a/super1.c b/super1.c +index 70aa1d3d0219..7b03329dac91 100644 +--- a/super1.c ++++ b/super1.c +@@ -1346,6 +1346,8 @@ static int update_super1(struct supertype *st, struct mdinfo *info, + memcpy(bms->uuid, sb->set_uuid, 16); + } else if (strcmp(update, "no-bitmap") == 0) { + sb->feature_map &= ~__cpu_to_le32(MD_FEATURE_BITMAP_OFFSET); ++ if (bms->version == BITMAP_MAJOR_CLUSTERED && !IsBitmapDirty(devname)) ++ sb->resync_offset = MaxSector; + } else if (strcmp(update, "bbl") == 0) { + /* only possible if there is room after the bitmap, or if + * there is no bitmap +-- +1.8.3.1 + diff --git a/mdadm.changes b/mdadm.changes index 88b9fa0..a6afc2c 100644 --- a/mdadm.changes +++ b/mdadm.changes @@ -1,3 +1,10 @@ +------------------------------------------------------------------- +Wed Mar 17 02:35:00 UTC 2021 - Heming Zhao + +- cluster-md/mdadm : avoid useless re-sync (bsc#1181341) + 0114-super1-fix-Floating-point-exception.patch + 0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch + ------------------------------------------------------------------- Tue Jan 5 12:02:12 UTC 2021 - Coly Li diff --git a/mdadm.spec b/mdadm.spec index dd1fd12..0ecdca9 100644 --- a/mdadm.spec +++ b/mdadm.spec @@ -150,6 +150,8 @@ Patch110: 0110-Make-target-to-install-binaries-only.patch Patch111: 0111-udev-start-grow-service-automatically.patch Patch112: 0112-Incremental-Remove-redundant-spare-movement-logic.patch Patch113: 0113-Dump-get-stat-from-a-wrong-metadata-file-when-restor.patch +Patch114: 0114-super1-fix-Floating-point-exception.patch +Patch115: 0115-super1.c-avoid-useless-sync-when-bitmap-switches-fro.patch Patch1001: 1001-display-timeout-status.patch Patch1002: 1002-OnCalendar-format-fix-of-mdcheck_start-timer.patch Patch1003: 1003-mdadm-treat-the-Dell-softraid-array-as-local-array.patch @@ -270,6 +272,8 @@ mdadm is a program that can be used to control Linux md devices. %patch111 -p1 %patch112 -p1 %patch113 -p1 +%patch114 -p1 +%patch115 -p1 %patch1001 -p1 %patch1002 -p1 %patch1003 -p1