kernel/linux.git/drivers/s390, branch v6.1.124

s390/cio: Do not unregister the subchannel based on DNV

2024-12-14T18:53:14+00:00

[ Upstream commit 8c58a229688ce3a097b3b1a2efe1b4f5508c2123 ] Starting with commit 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers"), CIO does not unregister subchannels when the attached device is invalid or unavailable. Instead, it allows subchannels to exist without a connected device. However, if the DNV value is 0, such as, when all the CHPIDs of a subchannel are configured in standby state, the subchannel is unregistered, which contradicts the current subchannel specification. Update the logic so that subchannels are not unregistered based on the DNV value. Also update the SCHIB information even if the DNV bit is zero. Suggested-by: Peter Oberparleiter Signed-off-by: Vineeth Vijayan Fixes: 2297791c92d0 ("s390/cio: dont unregister subchannel from child-drivers") Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

s390/sclp_vt220: Convert newlines to CRLF instead of LFCR

2024-10-22T13:56:44+00:00

commit dee3df68ab4b00fff6bdf9fc39541729af37307c upstream. According to the VT220 specification the possible character combinations sent on RETURN are only CR or CRLF [0]. The Return key sends either a CR character (0/13) or a CR character (0/13) and an LF character (0/10), depending on the set/reset state of line feed/new line mode (LNM). The sclp/vt220 driver however uses LFCR. This can confuse tools, for example the kunit runner. Link: https://vt100.net/docs/vt220-rm/chapter3.html#S3.2 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Reviewed-by: Sven Schnelle Link: https://lore.kernel.org/r/20241014-s390-kunit-v1-2-941defa765a6@linutronix.de Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390/sclp: Deactivate sclp after all its users

2024-10-22T13:56:44+00:00

commit 0d9dc27df22d9b5c8dc7185c8dddbc14f5468518 upstream. On reboot the SCLP interface is deactivated through a reboot notifier. This happens before other components using SCLP have the chance to run their own reboot notifiers. Two of those components are the SCLP console and tty drivers which try to flush the last outstanding messages. At that point the SCLP interface is already unusable and the messages are discarded. Execute sclp_deactivate() as late as possible to avoid this issue. Fixes: 4ae46db99cd8 ("s390/consoles: improve panic notifiers reliability") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Reviewed-by: Sven Schnelle Link: https://lore.kernel.org/r/20241014-s390-kunit-v1-1-941defa765a6@linutronix.de Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

Revert "s390/dasd: Establish DMA alignment"

2024-08-29T15:30:54+00:00

This reverts commit bc792884b76f ("s390/dasd: Establish DMA alignment"). Quoting the original commit: linux-next commit bf8d08532bc1 ("iomap: add support for dma aligned direct-io") changes the alignment requirement to come from the block device rather than the block size, and the default alignment requirement is 512-byte boundaries. Since DASD I/O has page alignments for IDAW/TIDAW requests, let's override this value to restore the expected behavior. I mentioned TIDAW, but that was wrong. TIDAWs have no distinct alignment requirement (per p. 15-70 of POPS SA22-7832-13): Unless otherwise specified, TIDAWs may designate a block of main storage on any boundary and length up to 4K bytes, provided the specified block does not cross a 4 K-byte boundary. IDAWs do, but the original commit neglected that while ECKD DASD are typically formatted in 4096-byte blocks, they don't HAVE to be. Formatting an ECKD volume with smaller blocks is permitted (dasdfmt -b xxx), and the problematic commit enforces alignment properties to such a device that will result in errors, such as: [test@host ~]# lsdasd -l a367 | grep blksz blksz: 512 [test@host ~]# mkfs.xfs -f /dev/disk/by-path/ccw-0.0.a367-part1 meta-data=/dev/dasdc1 isize=512 agcount=4, agsize=230075 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=1 = reflink=1 bigtime=1 inobtcount=1 nrext64=1 data = bsize=4096 blocks=920299, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=1 log =internal log bsize=4096 blocks=16384, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 error reading existing superblock: Invalid argument mkfs.xfs: pwrite failed: Invalid argument libxfs_bwrite: write failed on (unknown) bno 0x70565c/0x100, err=22 mkfs.xfs: Releasing dirty buffer to free list! found dirty buffer (bulk) on free list! mkfs.xfs: pwrite failed: Invalid argument ...snipped... The original commit omitted the FBA discipline for just this reason, but the formatted block size of the other disciplines was overlooked. The solution to all of this is to revert to the original behavior, such that the block size can be respected. But what of the original problem? That was manifested with a direct-io QEMU guest, where QEMU itself was changed a month or two later with commit 25474d90aa ("block: use the request length for iov alignment") such that the blamed kernel commit is unnecessary. Note: This is an adapted version of the original upstream commit 2a07bb64d801 ("s390/dasd: Remove DMA alignment"). Cc: stable@vger.kernel.org # 6.0+ Signed-off-by: Jan Höppner Signed-off-by: Greg Kroah-Hartman

bitmap: introduce generic optimized bitmap_size()

2024-08-29T15:30:14+00:00

commit a37fbe666c016fd89e4460d0ebfcea05baba46dc upstream. The number of times yet another open coded `BITS_TO_LONGS(nbits) * sizeof(long)` can be spotted is huge. Some generic helper is long overdue. Add one, bitmap_size(), but with one detail. BITS_TO_LONGS() uses DIV_ROUND_UP(). The latter works well when both divident and divisor are compile-time constants or when the divisor is not a pow-of-2. When it is however, the compilers sometimes tend to generate suboptimal code (GCC 13): 48 83 c0 3f add $0x3f,%rax 48 c1 e8 06 shr $0x6,%rax 48 8d 14 c5 00 00 00 00 lea 0x0(,%rax,8),%rdx %BITS_PER_LONG is always a pow-2 (either 32 or 64), but GCC still does full division of `nbits + 63` by it and then multiplication by 8. Instead of BITS_TO_LONGS(), use ALIGN() and then divide by 8. GCC: 8d 50 3f lea 0x3f(%rax),%edx c1 ea 03 shr $0x3,%edx 81 e2 f8 ff ff 1f and $0x1ffffff8,%edx Now it shifts `nbits + 63` by 3 positions (IOW performs fast division by 8) and then masks bits[2:0]. bloat-o-meter: add/remove: 0/0 grow/shrink: 20/133 up/down: 156/-773 (-617) Clang does it better and generates the same code before/after starting from -O1, except that with the ALIGN() approach it uses %edx and thus still saves some bytes: add/remove: 0/0 grow/shrink: 9/133 up/down: 18/-538 (-520) Note that we can't expand DIV_ROUND_UP() by adding a check and using this approach there, as it's used in array declarations where expressions are not allowed. Add this helper to tools/ as well. Reviewed-by: Przemek Kitszel Acked-by: Yury Norov Signed-off-by: Alexander Lobakin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

s390/cio: rename bitmap_size() -> idset_bitmap_size()

2024-08-29T15:30:14+00:00

commit c1023f5634b9bfcbfff0dc200245309e3cde9b54 upstream. bitmap_size() is a pretty generic name and one may want to use it for a generic bitmap API function. At the same time, its logic is not "generic", i.e. it's not just `nbits -> size of bitmap in bytes` converter as it would be expected from its name. Add the prefix 'idset_' used throughout the file where the function resides. Reviewed-by: Przemek Kitszel Acked-by: Peter Oberparleiter Signed-off-by: Alexander Lobakin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

s390/dasd: fix error recovery leading to data corruption on ESE devices

2024-08-29T15:30:13+00:00

commit 7db4042336580dfd75cb5faa82c12cd51098c90b upstream. Extent Space Efficient (ESE) or thin provisioned volumes need to be formatted on demand during usual IO processing. The dasd_ese_needs_format function checks for error codes that signal the non existence of a proper track format. The check for incorrect length is to imprecise since other error cases leading to transport of insufficient data also have this flag set. This might lead to data corruption in certain error cases for example during a storage server warmstart. Fix by removing the check for incorrect length and replacing by explicitly checking for invalid track format in transport mode. Also remove the check for file protected since this is not a valid ESE handling case. Cc: stable@vger.kernel.org # 5.3+ Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes") Reviewed-by: Jan Hoeppner Signed-off-by: Stefan Haberland Link: https://lore.kernel.org/r/20240812125733.126431-3-sth@linux.ibm.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

s390/sclp: Prevent release of buffer in I/O

2024-08-14T11:52:49+00:00

[ Upstream commit bf365071ea92b9579d5a272679b74052a5643e35 ] When a task waiting for completion of a Store Data operation is interrupted, an attempt is made to halt this operation. If this attempt fails due to a hardware or firmware problem, there is a chance that the SCLP facility might store data into buffers referenced by the original operation at a later time. Handle this situation by not releasing the referenced data buffers if the halt attempt fails. For current use cases, this might result in a leak of few pages of memory in case of a rare hardware/firmware malfunction. Reviewed-by: Heiko Carstens Signed-off-by: Peter Oberparleiter Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin

s390/dasd: fix error checks in dasd_copy_pair_store()

2024-08-03T06:49:29+00:00

[ Upstream commit 8e64d2356cbc800b4cd0e3e614797f76bcf0cdb8 ] dasd_add_busid() can return an error via ERR_PTR() if an allocation fails. However, two callsites in dasd_copy_pair_store() do not check the result, potentially resulting in a NULL pointer dereference. Fix this by checking the result with IS_ERR() and returning the error up the stack. Fixes: a91ff09d39f9b ("s390/dasd: add copy pair setup") Signed-off-by: Carlos López Signed-off-by: Stefan Haberland Link: https://lore.kernel.org/r/20240715112434.2111291-3-sth@linux.ibm.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

s390/sclp: Fix sclp_init() cleanup on failure

2024-07-25T07:49:15+00:00

[ Upstream commit 6434b33faaa063df500af355ee6c3942e0f8d982 ] If sclp_init() fails it only partially cleans up: if there are multiple failing calls to sclp_init() sclp_state_change_event will be added several times to sclp_reg_list, which results in the following warning: ------------[ cut here ]------------ list_add double add: new=000003ffe1598c10, prev=000003ffe1598bf0, next=000003ffe1598c10. WARNING: CPU: 0 PID: 1 at lib/list_debug.c:35 __list_add_valid_or_report+0xde/0xf8 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.10.0-rc3 Krnl PSW : 0404c00180000000 000003ffe0d6076a (__list_add_valid_or_report+0xe2/0xf8) R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 ... Call Trace: [<000003ffe0d6076a>] __list_add_valid_or_report+0xe2/0xf8 ([<000003ffe0d60766>] __list_add_valid_or_report+0xde/0xf8) [<000003ffe0a8d37e>] sclp_init+0x40e/0x450 [<000003ffe00009f2>] do_one_initcall+0x42/0x1e0 [<000003ffe15b77a6>] do_initcalls+0x126/0x150 [<000003ffe15b7a0a>] kernel_init_freeable+0x1ba/0x1f8 [<000003ffe0d6650e>] kernel_init+0x2e/0x180 [<000003ffe000301c>] __ret_from_fork+0x3c/0x60 [<000003ffe0d759ca>] ret_from_fork+0xa/0x30 Fix this by removing sclp_state_change_event from sclp_reg_list when sclp_init() fails. Reviewed-by: Peter Oberparleiter Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Sasha Levin