From patchwork Sat Feb 1 14:42:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11361051 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3FF4C924 for ; Sat, 1 Feb 2020 14:42:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E279206F0 for ; Sat, 1 Feb 2020 14:42:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726593AbgBAOmy (ORCPT ); Sat, 1 Feb 2020 09:42:54 -0500 Received: from mx2.suse.de ([195.135.220.15]:59036 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbgBAOmx (ORCPT ); Sat, 1 Feb 2020 09:42:53 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id EA40DAAFD; Sat, 1 Feb 2020 14:42:50 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 1/5] bcache: fix memory corruption in bch_cache_accounting_clear() Date: Sat, 1 Feb 2020 22:42:31 +0800 Message-Id: <20200201144235.94110-2-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200201144235.94110-1-colyli@suse.de> References: <20200201144235.94110-1-colyli@suse.de> MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Commit 83ff9318c44ba ("bcache: not use hard coded memset size in bch_cache_accounting_clear()") tries to make the code more easy to understand by removing the hard coded number with following change, void bch_cache_accounting_clear(...) { memset(&acc->total.cache_hits, 0, - sizeof(unsigned long) * 7); + sizeof(struct cache_stats)); } Unfortunately the change was wrong (it also tells us the original code was not easy to correctly understand). The hard coded number 7 is used because in struct cache_stats, 15 struct cache_stats { 16 struct kobject kobj; 17 18 unsigned long cache_hits; 19 unsigned long cache_misses; 20 unsigned long cache_bypass_hits; 21 unsigned long cache_bypass_misses; 22 unsigned long cache_readaheads; 23 unsigned long cache_miss_collisions; 24 unsigned long sectors_bypassed; 25 26 unsigned int rescale; 27 }; only members in LINE 18-24 want to be set to 0. It is wrong to use 'sizeof(struct cache_stats)' to replace 'sizeof(unsigned long) * 7), the memory objects behind acc->total is staled by this change. Сорокин Артем Сергеевич reports that by the following steps, kernel panic will be triggered, 1. Create new set: make-bcache -B /dev/nvme1n1 -C /dev/sda --wipe-bcache 2. Run in /sys/fs/bcache/: echo 1 > clear_stats && cat stats_five_minute/cache_bypass_hits I can reproduce the panic and get following dmesg with KASAN enabled, [22613.172742] ================================================================== [22613.172862] BUG: KASAN: null-ptr-deref in sysfs_kf_seq_show+0x117/0x230 [22613.172864] Read of size 8 at addr 0000000000000000 by task cat/6753 [22613.172870] CPU: 1 PID: 6753 Comm: cat Not tainted 5.5.0-rc7-lp151.28.16-default+ #11 [22613.172872] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019 [22613.172873] Call Trace: [22613.172964] dump_stack+0x8b/0xbb [22613.172968] ? sysfs_kf_seq_show+0x117/0x230 [22613.172970] ? sysfs_kf_seq_show+0x117/0x230 [22613.173031] __kasan_report+0x176/0x192 [22613.173064] ? pr_cont_kernfs_name+0x40/0x60 [22613.173067] ? sysfs_kf_seq_show+0x117/0x230 [22613.173070] kasan_report+0xe/0x20 [22613.173072] sysfs_kf_seq_show+0x117/0x230 [22613.173105] seq_read+0x199/0x6d0 [22613.173110] vfs_read+0xa5/0x1a0 [22613.173113] ksys_read+0x110/0x160 [22613.173115] ? kernel_write+0xb0/0xb0 [22613.173177] do_syscall_64+0x77/0x290 [22613.173238] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [22613.173241] RIP: 0033:0x7fc2c886ac61 [22613.173244] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89 [22613.173245] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [22613.173248] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61 [22613.173249] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003 [22613.173250] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000 [22613.173251] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000 [22613.173253] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000 [22613.173255] ================================================================== [22613.173256] Disabling lock debugging due to kernel taint [22613.173350] BUG: kernel NULL pointer dereference, address: 0000000000000000 [22613.178380] #PF: supervisor read access in kernel mode [22613.180959] #PF: error_code(0x0000) - not-present page [22613.183444] PGD 0 P4D 0 [22613.184867] Oops: 0000 [#1] SMP KASAN PTI [22613.186797] CPU: 1 PID: 6753 Comm: cat Tainted: G B 5.5.0-rc7-lp151.28.16-default+ #11 [22613.191253] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/29/2019 [22613.196706] RIP: 0010:sysfs_kf_seq_show+0x117/0x230 [22613.199097] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48 [22613.208016] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246 [22613.210448] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6 [22613.213691] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246 [22613.216893] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd [22613.220075] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200 [22613.223256] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000 [22613.226290] FS: 00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000 [22613.229637] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [22613.231993] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0 [22613.234909] Call Trace: [22613.235931] seq_read+0x199/0x6d0 [22613.237259] vfs_read+0xa5/0x1a0 [22613.239229] ksys_read+0x110/0x160 [22613.240590] ? kernel_write+0xb0/0xb0 [22613.242040] do_syscall_64+0x77/0x290 [22613.243625] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [22613.245450] RIP: 0033:0x7fc2c886ac61 [22613.246706] Code: fe ff ff 48 8d 3d c7 a0 09 00 48 83 ec 08 e8 46 03 02 00 66 0f 1f 44 00 00 8b 05 ca fb 2c 00 48 63 ff 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48 89 [22613.253296] RSP: 002b:00007ffebe776d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [22613.255835] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2c886ac61 [22613.258472] RDX: 0000000000020000 RSI: 00007fc2c8cca000 RDI: 0000000000000003 [22613.260807] RBP: 0000000000020000 R08: ffffffffffffffff R09: 0000000000000000 [22613.263188] R10: 000000000000038c R11: 0000000000000246 R12: 00007fc2c8cca000 [22613.265598] R13: 0000000000000003 R14: 00007fc2c8cca00f R15: 0000000000020000 [22613.268729] Modules linked in: scsi_transport_iscsi af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock fuse bnep kvm_intel kvm irqbypass crc32_pclmul crc32c_intel ghash_clmulni_intel snd_ens1371 snd_ac97_codec ac97_bus bcache snd_pcm btusb btrtl btbcm btintel crc64 aesni_intel glue_helper crypto_simd vmw_balloon cryptd bluetooth snd_timer snd_rawmidi snd joydev pcspkr e1000 rfkill vmw_vmci soundcore ecdh_generic ecc gameport i2c_piix4 mptctl ac button hid_generic usbhid sr_mod cdrom ata_generic ehci_pci vmwgfx uhci_hcd drm_kms_helper syscopyarea serio_raw sysfillrect sysimgblt fb_sys_fops ttm ehci_hcd mptspi scsi_transport_spi mptscsih ata_piix mptbase ahci usbcore libahci drm sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua [22613.292429] CR2: 0000000000000000 [22613.293563] ---[ end trace a074b26a8508f378 ]--- [22613.295138] RIP: 0010:sysfs_kf_seq_show+0x117/0x230 [22613.296769] Code: ff 48 8b 0b 48 8b 44 24 08 48 01 e9 eb a6 31 f6 48 89 cf ba 00 10 00 00 48 89 4c 24 10 e8 b1 e6 e9 ff 4c 89 ff e8 19 07 ea ff <49> 8b 07 48 85 c0 48 89 44 24 08 0f 84 91 00 00 00 49 8b 6d 00 48 [22613.303553] RSP: 0018:ffff8881d4f8fd78 EFLAGS: 00010246 [22613.305280] RAX: 0000000000000000 RBX: ffff8881eb99b180 RCX: ffffffff810d9ef6 [22613.307924] RDX: 0000000000000001 RSI: 0000000000000246 RDI: 0000000000000246 [22613.310272] RBP: 0000000000001000 R08: fffffbfff072ddcd R09: fffffbfff072ddcd [22613.312685] R10: 0000000000000001 R11: fffffbfff072ddcc R12: ffff8881de5c0200 [22613.315076] R13: ffff8881ed175500 R14: ffff8881eb99b198 R15: 0000000000000000 [22613.318116] FS: 00007fc2c8d3d500(0000) GS:ffff8881f2a80000(0000) knlGS:0000000000000000 [22613.320743] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [22613.322628] CR2: 0000000000000000 CR3: 00000001ec89a004 CR4: 00000000003606e0 Here this patch fixes the following problem by explicity set all the 7 members to 0 in bch_cache_accounting_clear(). Reported-by: Сорокин Артем Сергеевич Signed-off-by: Coly Li --- drivers/md/bcache/stats.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/md/bcache/stats.c b/drivers/md/bcache/stats.c index ba1c93791d8d..503aafe188dc 100644 --- a/drivers/md/bcache/stats.c +++ b/drivers/md/bcache/stats.c @@ -109,9 +109,13 @@ int bch_cache_accounting_add_kobjs(struct cache_accounting *acc, void bch_cache_accounting_clear(struct cache_accounting *acc) { - memset(&acc->total.cache_hits, - 0, - sizeof(struct cache_stats)); + acc->total.cache_hits = 0; + acc->total.cache_misses = 0; + acc->total.cache_bypass_hits = 0; + acc->total.cache_bypass_misses = 0; + acc->total.cache_readaheads = 0; + acc->total.cache_miss_collisions = 0; + acc->total.sectors_bypassed = 0; } void bch_cache_accounting_destroy(struct cache_accounting *acc) From patchwork Sat Feb 1 14:42:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11361053 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4D0EE924 for ; Sat, 1 Feb 2020 14:42:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35D87206F0 for ; Sat, 1 Feb 2020 14:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726668AbgBAOm5 (ORCPT ); Sat, 1 Feb 2020 09:42:57 -0500 Received: from mx2.suse.de ([195.135.220.15]:59082 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbgBAOm4 (ORCPT ); Sat, 1 Feb 2020 09:42:56 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 38DB8AAFD; Sat, 1 Feb 2020 14:42:55 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 2/5] bcache: explicity type cast in bset_bkey_last() Date: Sat, 1 Feb 2020 22:42:32 +0800 Message-Id: <20200201144235.94110-3-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200201144235.94110-1-colyli@suse.de> References: <20200201144235.94110-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org In bset.h, macro bset_bkey_last() is defined as, bkey_idx((struct bkey *) (i)->d, (i)->keys) Parameter i can be variable type of data structure, the macro always works once the type of struct i has member 'd' and 'keys'. bset_bkey_last() is also used in macro csum_set() to calculate the checksum of a on-disk data structure. When csum_set() is used to calculate checksum of on-disk bcache super block, the parameter 'i' data type is struct cache_sb_disk. Inside struct cache_sb_disk (also in struct cache_sb) the member keys is __u16 type. But bkey_idx() expects unsigned int (a 32bit width), so there is problem when sending parameters via stack to call bkey_idx(). Sparse tool from Intel 0day kbuild system reports this incompatible problem. bkey_idx() is part of user space API, so the simplest fix is to cast the (i)->keys to unsigned int type in macro bset_bkey_last(). Reported-by: kbuild test robot Signed-off-by: Coly Li --- drivers/md/bcache/bset.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h index c71365e7c1fa..a50dcfda656f 100644 --- a/drivers/md/bcache/bset.h +++ b/drivers/md/bcache/bset.h @@ -397,7 +397,8 @@ void bch_btree_keys_stats(struct btree_keys *b, struct bset_stats *state); /* Bkey utility code */ -#define bset_bkey_last(i) bkey_idx((struct bkey *) (i)->d, (i)->keys) +#define bset_bkey_last(i) bkey_idx((struct bkey *) (i)->d, \ + (unsigned int)(i)->keys) static inline struct bkey *bset_bkey_idx(struct bset *i, unsigned int idx) { From patchwork Sat Feb 1 14:42:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11361055 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A83A413B4 for ; Sat, 1 Feb 2020 14:43:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90A5E206F0 for ; Sat, 1 Feb 2020 14:43:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726679AbgBAOnF (ORCPT ); Sat, 1 Feb 2020 09:43:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:59104 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726670AbgBAOnF (ORCPT ); Sat, 1 Feb 2020 09:43:05 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2A441AAFD; Sat, 1 Feb 2020 14:43:02 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li , stable@vger.kernel.org, Michael Lyle Subject: [PATCH 3/5] bcache: add readahead cache policy options via sysfs interface Date: Sat, 1 Feb 2020 22:42:33 +0800 Message-Id: <20200201144235.94110-4-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200201144235.94110-1-colyli@suse.de> References: <20200201144235.94110-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org In year 2007 high performance SSD was still expensive, in order to save more space for real workload or meta data, the readahead I/Os for non-meta data was bypassed and not cached on SSD. In now days, SSD price drops a lot and people can find larger size SSD with more comfortable price. It is unncessary to alway bypass normal readahead I/Os to save SSD space for now. This patch adds options for readahead data cache policies via sysfs file /sys/block/bcache/readahead_cache_policy, the options are, - "all": cache all readahead data I/Os. - "meta-only": only cache meta data, and bypass other regular I/Os. If users want to make bcache continue to only cache readahead request for metadata and bypass regular data readahead, please set "meta-only" to this sysfs file. By default, bcache will back to cache all read- ahead requests now. Cc: stable@vger.kernel.org Signed-off-by: Coly Li Acked-by: Eric Wheeler Cc: Michael Lyle --- drivers/md/bcache/bcache.h | 3 +++ drivers/md/bcache/request.c | 17 ++++++++++++----- drivers/md/bcache/sysfs.c | 22 ++++++++++++++++++++++ 3 files changed, 37 insertions(+), 5 deletions(-) diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index adf26a21fcd1..74a9849ea164 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -330,6 +330,9 @@ struct cached_dev { */ atomic_t has_dirty; +#define BCH_CACHE_READA_ALL 0 +#define BCH_CACHE_READA_META_ONLY 1 + unsigned int cache_readahead_policy; struct bch_ratelimit writeback_rate; struct delayed_work writeback_rate_update; diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index 73478a91a342..820d8402a1dc 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -379,13 +379,20 @@ static bool check_should_bypass(struct cached_dev *dc, struct bio *bio) goto skip; /* - * Flag for bypass if the IO is for read-ahead or background, - * unless the read-ahead request is for metadata + * If the bio is for read-ahead or background IO, bypass it or + * not depends on the following situations, + * - If the IO is for meta data, always cache it and no bypass + * - If the IO is not meta data, check dc->cache_reada_policy, + * BCH_CACHE_READA_ALL: cache it and not bypass + * BCH_CACHE_READA_META_ONLY: not cache it and bypass + * That is, read-ahead request for metadata always get cached * (eg, for gfs2 or xfs). */ - if (bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND) && - !(bio->bi_opf & (REQ_META|REQ_PRIO))) - goto skip; + if ((bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND))) { + if (!(bio->bi_opf & (REQ_META|REQ_PRIO)) && + (dc->cache_readahead_policy != BCH_CACHE_READA_ALL)) + goto skip; + } if (bio->bi_iter.bi_sector & (c->sb.block_size - 1) || bio_sectors(bio) & (c->sb.block_size - 1)) { diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 733e2ddf3c78..3470fae4eabc 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -27,6 +27,12 @@ static const char * const bch_cache_modes[] = { NULL }; +static const char * const bch_reada_cache_policies[] = { + "all", + "meta-only", + NULL +}; + /* Default is 0 ("auto") */ static const char * const bch_stop_on_failure_modes[] = { "auto", @@ -100,6 +106,7 @@ rw_attribute(congested_write_threshold_us); rw_attribute(sequential_cutoff); rw_attribute(data_csum); rw_attribute(cache_mode); +rw_attribute(readahead_cache_policy); rw_attribute(stop_when_cache_set_failed); rw_attribute(writeback_metadata); rw_attribute(writeback_running); @@ -168,6 +175,11 @@ SHOW(__bch_cached_dev) bch_cache_modes, BDEV_CACHE_MODE(&dc->sb)); + if (attr == &sysfs_readahead_cache_policy) + return bch_snprint_string_list(buf, PAGE_SIZE, + bch_reada_cache_policies, + dc->cache_readahead_policy); + if (attr == &sysfs_stop_when_cache_set_failed) return bch_snprint_string_list(buf, PAGE_SIZE, bch_stop_on_failure_modes, @@ -353,6 +365,15 @@ STORE(__cached_dev) } } + if (attr == &sysfs_readahead_cache_policy) { + v = __sysfs_match_string(bch_reada_cache_policies, -1, buf); + if (v < 0) + return v; + + if ((unsigned int) v != dc->cache_readahead_policy) + dc->cache_readahead_policy = v; + } + if (attr == &sysfs_stop_when_cache_set_failed) { v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf); if (v < 0) @@ -467,6 +488,7 @@ static struct attribute *bch_cached_dev_files[] = { &sysfs_data_csum, #endif &sysfs_cache_mode, + &sysfs_readahead_cache_policy, &sysfs_stop_when_cache_set_failed, &sysfs_writeback_metadata, &sysfs_writeback_running, From patchwork Sat Feb 1 14:42:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11361057 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C8EED13B4 for ; Sat, 1 Feb 2020 14:43:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B17EB206F0 for ; Sat, 1 Feb 2020 14:43:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726718AbgBAOnI (ORCPT ); Sat, 1 Feb 2020 09:43:08 -0500 Received: from mx2.suse.de ([195.135.220.15]:59114 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726670AbgBAOnI (ORCPT ); Sat, 1 Feb 2020 09:43:08 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 9337FAAFD; Sat, 1 Feb 2020 14:43:06 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 4/5] bcache: fix incorrect data type usage in btree_flush_write() Date: Sat, 1 Feb 2020 22:42:34 +0800 Message-Id: <20200201144235.94110-5-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200201144235.94110-1-colyli@suse.de> References: <20200201144235.94110-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Dan Carpenter points out that from commit 2aa8c529387c ("bcache: avoid unnecessary btree nodes flushing in btree_flush_write()"), there is a incorrect data type usage which leads to the following static checker warning: drivers/md/bcache/journal.c:444 btree_flush_write() warn: 'ref_nr' unsigned <= 0 drivers/md/bcache/journal.c 422 static void btree_flush_write(struct cache_set *c) 423 { 424 struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR]; 425 unsigned int i, nr, ref_nr; ^^^^^^ 426 atomic_t *fifo_front_p, *now_fifo_front_p; 427 size_t mask; 428 429 if (c->journal.btree_flushing) 430 return; 431 432 spin_lock(&c->journal.flush_write_lock); 433 if (c->journal.btree_flushing) { 434 spin_unlock(&c->journal.flush_write_lock); 435 return; 436 } 437 c->journal.btree_flushing = true; 438 spin_unlock(&c->journal.flush_write_lock); 439 440 /* get the oldest journal entry and check its refcount */ 441 spin_lock(&c->journal.lock); 442 fifo_front_p = &fifo_front(&c->journal.pin); 443 ref_nr = atomic_read(fifo_front_p); 444 if (ref_nr <= 0) { ^^^^^^^^^^^ Unsigned can't be less than zero. 445 /* 446 * do nothing if no btree node references 447 * the oldest journal entry 448 */ 449 spin_unlock(&c->journal.lock); 450 goto out; 451 } 452 spin_unlock(&c->journal.lock); As the warning information indicates, local varaible ref_nr in unsigned int type is wrong, which does not matche atomic_read() and the "<= 0" checking. This patch fixes the above error by defining local variable ref_nr as int type. Fixes: 2aa8c529387c ("bcache: avoid unnecessary btree nodes flushing in btree_flush_write()") Reported-by: Dan Carpenter Signed-off-by: Coly Li --- drivers/md/bcache/journal.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c index 33ddc5269e8d..6730820780b0 100644 --- a/drivers/md/bcache/journal.c +++ b/drivers/md/bcache/journal.c @@ -422,7 +422,8 @@ int bch_journal_replay(struct cache_set *s, struct list_head *list) static void btree_flush_write(struct cache_set *c) { struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR]; - unsigned int i, nr, ref_nr; + unsigned int i, nr; + int ref_nr; atomic_t *fifo_front_p, *now_fifo_front_p; size_t mask; From patchwork Sat Feb 1 14:42:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11361059 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 98B07924 for ; Sat, 1 Feb 2020 14:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 77EFE2070C for ; Sat, 1 Feb 2020 14:43:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726773AbgBAOnN (ORCPT ); Sat, 1 Feb 2020 09:43:13 -0500 Received: from mx2.suse.de ([195.135.220.15]:59128 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726670AbgBAOnM (ORCPT ); Sat, 1 Feb 2020 09:43:12 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 08EADB197; Sat, 1 Feb 2020 14:43:11 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 5/5] bcache: check return value of prio_read() Date: Sat, 1 Feb 2020 22:42:35 +0800 Message-Id: <20200201144235.94110-6-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20200201144235.94110-1-colyli@suse.de> References: <20200201144235.94110-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Now if prio_read() failed during starting a cache set, we can print out error message in run_cache_set() and handle the failure properly. Signed-off-by: Coly Li --- drivers/md/bcache/super.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 3dea1d5acd5c..2749daf09724 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -609,12 +609,13 @@ int bch_prio_write(struct cache *ca, bool wait) return 0; } -static void prio_read(struct cache *ca, uint64_t bucket) +static int prio_read(struct cache *ca, uint64_t bucket) { struct prio_set *p = ca->disk_buckets; struct bucket_disk *d = p->data + prios_per_bucket(ca), *end = d; struct bucket *b; unsigned int bucket_nr = 0; + int ret = -EIO; for (b = ca->buckets; b < ca->buckets + ca->sb.nbuckets; @@ -627,11 +628,15 @@ static void prio_read(struct cache *ca, uint64_t bucket) prio_io(ca, bucket, REQ_OP_READ, 0); if (p->csum != - bch_crc64(&p->magic, bucket_bytes(ca) - 8)) + bch_crc64(&p->magic, bucket_bytes(ca) - 8)) { pr_warn("bad csum reading priorities"); + goto out; + } - if (p->magic != pset_magic(&ca->sb)) + if (p->magic != pset_magic(&ca->sb)) { pr_warn("bad magic reading priorities"); + goto out; + } bucket = p->next_bucket; d = p->data; @@ -640,6 +645,10 @@ static void prio_read(struct cache *ca, uint64_t bucket) b->prio = le16_to_cpu(d->prio); b->gen = b->last_gc = d->gen; } + + ret = 0; +out: + return ret; } /* Bcache device */ @@ -1873,8 +1882,10 @@ static int run_cache_set(struct cache_set *c) j = &list_entry(journal.prev, struct journal_replay, list)->j; err = "IO error reading priorities"; - for_each_cache(ca, c, i) - prio_read(ca, j->prio_bucket[ca->sb.nr_this_dev]); + for_each_cache(ca, c, i) { + if (prio_read(ca, j->prio_bucket[ca->sb.nr_this_dev])) + goto err; + } /* * If prio_read() fails it'll call cache_set_error and we'll