kernel/drivers/s390/char/zcore.c, branch linux-6.9.y

s390/switch_to: use generic header file

2024-02-12T14:03:33Z

Move the switch_to() implementation to process.c and use the generic switch_to.h header file instead, like some other architectures. This addresses also the oddity that the old switch_to() implementation assigns the return value of __switch_to() to 'prev' instead of 'last', like it should. Remove also all includes of switch_to.h from C files, except process.c. Acked-by: Alexander Gordeev Signed-off-by: Heiko Carstens

docs: move s390 under arch

2023-07-24T10:12:24Z

and fix all in-tree references. Architecture-specific documentation is being moved into Documentation/arch/ as a way of cleaning up the top-level documentation directory and making the docs hierarchy more closely match the source hierarchy. Signed-off-by: Costa Shulyupin Reviewed-by: Tony Krowiak Acked-by: Jonathan Corbet Acked-by: Heiko Carstens Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Randy Dunlap Link: https://lore.kernel.org/r/20230718045550.495428-1-costa.shul@redhat.com Signed-off-by: Heiko Carstens

s390/zcore: conditionally clear memory on reipl

2023-06-01T15:07:56Z

Currently zcore_reipl_write() always use DIAG308_LOAD_CLEAR to ipl the system (used by ngdump and zfcpdump to ipl the original kernel after dumping). Instead of 'always clear' check OS_INFO_FLAG_REIPL_CLEAR flag and use either LOAD_CLEAR or LOAD_NORMAL diag308 subcode accordingly. For that read os_info and check for the valid os_info flags entry in zcore_reipl_init(). Do not return error on failure (e.g. os_info checksum error) in order to continue dump processing, considering that os_info could be corrupted on the panicked system. Signed-off-by: Mikhail Zaslonko Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev

Merge tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-12-13T02:29:54Z

Pull iov_iter updates from Al Viro: "iov_iter work; most of that is about getting rid of direction misannotations and (hopefully) preventing more of the same for the future" * tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: use less confusing names for iov_iter direction initializers iov_iter: saner checks for attempt to copy to/from iterator [xen] fix "direction" argument of iov_iter_kvec() [vhost] fix 'direction' argument of iov_iter_{init,bvec}() [target] fix iov_iter_bvec() "direction" argument [s390] memcpy_real(): WRITE is "data source", not destination... [s390] zcore: WRITE is "data source", not destination... [infiniband] READ is "data destination", not source... [fsi] WRITE is "data source", not destination... [s390] copy_oldmem_kernel() - WRITE is "data source", not destination csum_and_copy_to_iter(): handle ITER_DISCARD get rid of unlikely() on page_copy_sane() calls

s390/ipl: add eckd dump support

2022-12-06T15:18:22Z

This adds support to use ECKD disks as dump device to linux. The new dump type is called 'eckd_dump', parameters are the same as for eckd ipl. Signed-off-by: Sven Schnelle Reviewed-by: Vasily Gorbik Signed-off-by: Alexander Gordeev

use less confusing names for iov_iter direction initializers

2022-11-25T18:01:55Z

READ/WRITE proved to be actively confusing - the meanings are "data destination, as used with read(2)" and "data source, as used with write(2)", but people keep interpreting those as "we read data from it" and "we write data to it", i.e. exactly the wrong way. Call them ITER_DEST and ITER_SOURCE - at least that is harder to misinterpret... Signed-off-by: Al Viro

[s390] zcore: WRITE is "data source", not destination...

2022-11-25T18:01:21Z

Signed-off-by: Al Viro

s390/mm: rework memcpy_real() to avoid DAT-off mode

2022-09-14T14:46:01Z

Function memcpy_real() is an univeral data mover that does not require DAT mode to be able reading from a physical address. Its advantage is an ability to read from any address, even those for which no kernel virtual mapping exists. Although memcpy_real() is interrupt-safe, there are no handlers that make use of this function. The compiler instrumentation have to be disabled and separate no-DAT stack used to allow execution of the function once DAT mode is disabled. Rework memcpy_real() to overcome these shortcomings. As result, data copying (which is primarily reading out a crashed system memory by a user process) is executed on a regular stack with enabled interrupts. Also, use of memcpy_real_buf swap buffer becomes unnecessary and the swapping is eliminated. The above is achieved by using a fixed virtual address range that spans a single page and remaps that page repeatedly when memcpy_real() is called for a particular physical address. Reviewed-by: Heiko Carstens Signed-off-by: Alexander Gordeev Signed-off-by: Vasily Gorbik

s390/crash: support multi-segment iterators

2022-07-20T15:21:41Z

Make it possible to handle not only single-, but also multi- segment iterators in copy_oldmem_iter() callback. Change the semantics of called functions to match the iterator model - instead of an error code the exact number of bytes copied is returned. The swap page used to copy data to user space is adopted for kernel space too. That does not bring any performance impact. Suggested-by: Matthew Wilcox Fixes: cc02e6e21aa5 ("s390/crash: add missing iterator advance in copy_oldmem_page()") Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/5af6da3a0bffe48a90b0b7139ecf6a818b2d18e8.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev

s390/zcore: fix race when reading from hardware system area

2022-07-20T15:21:41Z

Memory buffer used for reading out data from hardware system area is not protected against concurrent access. Reported-by: Matthew Wilcox Fixes: 411ed3225733 ("[S390] zfcpdump support.") Acked-by: Heiko Carstens Tested-by: Alexander Egorenkov Link: https://lore.kernel.org/r/e68137f0f9a0d2558f37becc20af18e2939934f6.1658206891.git.agordeev@linux.ibm.com Signed-off-by: Alexander Gordeev