kernel/linux.git/drivers/s390/scsi, branch v6.12.91

scsi: s390: zfcp: Ensure synchronous unit_add

2025-06-27T10:11:37+00:00

commit 9697ca0d53e3db357be26d2414276143c4a2cd49 upstream. Improve the usability of the unit_add sysfs attribute by ensuring that the associated FCP LUN scan processing is completed synchronously. This enables configuration tooling to consistently determine the end of the scan process to allow for serialization of follow-on actions. While the scan process associated with unit_add typically completes synchronously, it is deferred to an asynchronous background process if unit_add is used before initial remote port scanning has completed. This occurs when unit_add is used immediately after setting the associated FCP device online. To ensure synchronous unit_add processing, wait for remote port scanning to complete before initiating the FCP LUN scan. Cc: stable@vger.kernel.org Reviewed-by: M Nikhil Reviewed-by: Nihar Panda Signed-off-by: Peter Oberparleiter Signed-off-by: Nihar Panda Link: https://lore.kernel.org/r/20250603182252.2287285-2-niharp@linux.ibm.com Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

s390/zfcp: use new address translation helpers

2024-03-13T08:23:48+00:00

Use virt_to_dma64() and friends to properly convert virtual to physical and physical to virtual addresses so that "make C=1" does not generate any warnings anymore. Reviewed-by: Steffen Maier Signed-off-by: Heiko Carstens

scsi: zfcp: Replace strlcpy() with strscpy()

2023-12-06T02:01:52+00:00

strlcpy() reads the entire source buffer first. This read may exceed the destination size limit. This is both inefficient and can lead to linear read overflows if a source string is not NUL-terminated[1]. Additionally, it returns the size of the source string, not the resulting size of the destination string. In an effort to remove strlcpy() completely[2], replace strlcpy() here with strscpy(). Overflow should be impossible here, but actually check for buffer sizes being identical with BUILD_BUG_ON(), and include a run-time check as well. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy [1] Link: https://github.com/KSPP/linux/issues/89 [2] Cc: Martin K. Petersen Cc: James E.J. Bottomley Cc: Steffen Maier Cc: Benjamin Block Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Sven Schnelle Cc: Azeem Shaikh Cc: Cc: Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20231130204056.it.978-kees@kernel.org Acked-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: Fix a double put in zfcp_port_enqueue()

2023-09-27T15:31:20+00:00

When device_register() fails, zfcp_port_release() will be called after put_device(). As a result, zfcp_ccw_adapter_put() will be called twice: one in zfcp_port_release() and one in the error path after device_register(). So the reference on the adapter object is doubly put, which may lead to a premature free. Fix this by adjusting the error tag after device_register(). Fixes: f3450c7b9172 ("[SCSI] zfcp: Replace local reference counting with common kref") Signed-off-by: Dinghao Liu Link: https://lore.kernel.org/r/20230923103723.10320-1-dinghao.liu@zju.edu.cn Acked-by: Benjamin Block Cc: stable@vger.kernel.org # v2.6.33+ Signed-off-by: Martin K. Petersen

scsi: zfcp: Defer fc_rport blocking until after ADISC response

2023-07-26T01:54:05+00:00

Storage devices are free to send RSCNs, e.g. for internal state changes. If this happens on all connected paths, zfcp risks temporarily losing all paths at the same time. This has strong requirements on multipath configuration such as "no_path_retry queue". Avoid such situations by deferring fc_rport blocking until after the ADISC response, when any actual state change of the remote port became clear. The already existing port recovery triggers explicitly block the fc_rport. The triggers are: on ADISC reject or timeout (typical cable pull case), and on ADISC indicating that the remote port has changed its WWPN or the port is meanwhile no longer open. As a side effect, this also removes a confusing direct function call to another work item function zfcp_scsi_rport_work() instead of scheduling that other work item. It was probably done that way to have the rport block side effect immediate and synchronous to the caller. Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors") Cc: stable@vger.kernel.org #v2.6.30+ Reviewed-by: Benjamin Block Reviewed-by: Fedor Loshakov Signed-off-by: Steffen Maier Link: https://lore.kernel.org/r/20230724145156.3920244-1-maier@linux.ibm.com Signed-off-by: Martin K. Petersen

scsi: zfcp: Declare SCSI host template const

2023-03-24T23:19:20+00:00

Make it explicit that the SCSI host template is not modified. Acked-by: Benjamin Block Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230322195515.1267197-9-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: zfcp: Trace when request remove fails after qdio send fails

2023-02-22T03:00:51+00:00

When we fail to send a FSF request in 'zfcp_fsf_req_send()' when calling 'zfcp_qdio_send()' we try to remove the request object from our internal hash table again to prevent keeping a stale memory reference. This removal might still - very much theoretically - fail. To store some evidence of when this happens add a new trace record for this case; tag: 'fsrsrmf'. We reuse the 'ZFCP_DBF_HBA_RES' trace ID for this, but mark all fields other then the request ID with ~0, to make fairly obvious that these are invalid values. This faking has to be done because we don't have a valid request object at this point, and can not safely access any of the memory of the old object - we just failed to find it in our hash table, so it might be gone already. Here is an example of a decoded trace record: Timestamp : 2023-02-17-13:09:12:748140 Area : HBA Subarea : 1 Level : - Exception : 000003ff7ff500c2 CPU ID : 0011 Caller : 0x0 Record ID : 1 Tag : fsrsrmf Request ID : 0x0000000080126ab6 Request status : 0xffffffff FSF cmnd : 0xffffffff FSF sequence no: 0xffffffff FSF issued : 2042-09-18-01:53:47:370495 FSF stat : 0xffffffff FSF stat qual : ffffffff ffffffff ffffffff ffffffff Prot stat : 0xffffffff Prot stat qual : ffffffff ffffffff ffffffff ffffffff Port handle : 0xffffffff LUN handle : 0xffffffff This provides at least some basic evidence that this event happened, and what object was affected. Link: https://lore.kernel.org/r/99b8246b2d71b63fa4f9c56333e2037502f7f5af.1677000450.git.bblock@linux.ibm.com Signed-off-by: Benjamin Block Reviewed-by: Steffen Maier Signed-off-by: Martin K. Petersen

scsi: zfcp: Change the type of all fsf request id fields and variables to u64

2023-02-22T03:00:51+00:00

We use different integer types throughout zfcp to store the FSF request ID and related values; some places use 'unsigned long' and others 'u64'. On s390x these are effectively the same type, but this might cause confusions and is generally inconsistent. The specification for the used hardware specifies this value as a 64-bit number, and ultimately we use this value to communicate with the hardware, so it makes sense to change the type of all these variables to 'u64' where we can. The only exception being when we store it in the 'host_scribble' field of a 'struct scsi_cmnd'; for this case we add a build time check to make sure they are compatible. Link: https://lore.kernel.org/r/9c9cbe5acc2b419a22dce2fed847e3db91b60201.1677000450.git.bblock@linux.ibm.com Signed-off-by: Benjamin Block Reviewed-by: Steffen Maier Signed-off-by: Martin K. Petersen

scsi: zfcp: Make the type for accessing request hashtable buckets size_t

2023-02-22T03:00:51+00:00

The appropriate type for array indices is 'size_t' and the current implementation in 'zfcp_reqlist.h' mixes 'int' and 'unsigned int' in different places to access the hashtable buckets of our internal request hash table. To prevent any confusion, change all places to 'size_t'. Link: https://lore.kernel.org/r/64afe93f6263c6b07815937826cd7d5fc4f1a674.1677000450.git.bblock@linux.ibm.com Signed-off-by: Benjamin Block Reviewed-by: Steffen Maier Signed-off-by: Martin K. Petersen

Merge tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

2022-12-13T00:22:22+00:00

Pull random number generator updates from Jason Donenfeld: - Replace prandom_u32_max() and various open-coded variants of it, there is now a new family of functions that uses fast rejection sampling to choose properly uniformly random numbers within an interval: get_random_u32_below(ceil) - [0, ceil) get_random_u32_above(floor) - (floor, U32_MAX] get_random_u32_inclusive(floor, ceil) - [floor, ceil] Coccinelle was used to convert all current users of prandom_u32_max(), as well as many open-coded patterns, resulting in improvements throughout the tree. I'll have a "late" 6.1-rc1 pull for you that removes the now unused prandom_u32_max() function, just in case any other trees add a new use case of it that needs to converted. According to linux-next, there may be two trivial cases of prandom_u32_max() reintroductions that are fixable with a 's/.../.../'. So I'll have for you a final conversion patch doing that alongside the removal patch during the second week. This is a treewide change that touches many files throughout. - More consistent use of get_random_canary(). - Updates to comments, documentation, tests, headers, and simplification in configuration. - The arch_get_random*_early() abstraction was only used by arm64 and wasn't entirely useful, so this has been replaced by code that works in all relevant contexts. - The kernel will use and manage random seeds in non-volatile EFI variables, refreshing a variable with a fresh seed when the RNG is initialized. The RNG GUID namespace is then hidden from efivarfs to prevent accidental leakage. These changes are split into random.c infrastructure code used in the EFI subsystem, in this pull request, and related support inside of EFISTUB, in Ard's EFI tree. These are co-dependent for full functionality, but the order of merging doesn't matter. - Part of the infrastructure added for the EFI support is also used for an improvement to the way vsprintf initializes its siphash key, replacing an sleep loop wart. - The hardware RNG framework now always calls its correct random.c input function, add_hwgenerator_randomness(), rather than sometimes going through helpers better suited for other cases. - The add_latent_entropy() function has long been called from the fork handler, but is a no-op when the latent entropy gcc plugin isn't used, which is fine for the purposes of latent entropy. But it was missing out on the cycle counter that was also being mixed in beside the latent entropy variable. So now, if the latent entropy gcc plugin isn't enabled, add_latent_entropy() will expand to a call to add_device_randomness(NULL, 0), which adds a cycle counter, without the absent latent entropy variable. - The RNG is now reseeded from a delayed worker, rather than on demand when used. Always running from a worker allows it to make use of the CPU RNG on platforms like S390x, whose instructions are too slow to do so from interrupts. It also has the effect of adding in new inputs more frequently with more regularity, amounting to a long term transcript of random values. Plus, it helps a bit with the upcoming vDSO implementation (which isn't yet ready for 6.2). - The jitter entropy algorithm now tries to execute on many different CPUs, round-robining, in hopes of hitting even more memory latencies and other unpredictable effects. It also will mix in a cycle counter when the entropy timer fires, in addition to being mixed in from the main loop, to account more explicitly for fluctuations in that timer firing. And the state it touches is now kept within the same cache line, so that it's assured that the different execution contexts will cause latencies. * tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits) random: include in the right header random: align entropy_timer_state to cache line random: mix in cycle counter when jitter timer fires random: spread out jitter callback to different CPUs random: remove extraneous period and add a missing one in comments efi: random: refresh non-volatile random seed when RNG is initialized vsprintf: initialize siphash key using notifier random: add back async readiness notifier random: reseed in delayed work rather than on-demand random: always mix cycle counter in add_latent_entropy() hw_random: use add_hwgenerator_randomness() for early entropy random: modernize documentation comment on get_random_bytes() random: adjust comment to account for removed function random: remove early archrandom abstraction random: use random.trust_{bootloader,cpu} command line option only stackprotector: actually use get_random_canary() stackprotector: move get_random_canary() into stackprotector.h treewide: use get_random_u32_inclusive() when possible treewide: use get_random_u32_{above,below}() instead of manual loop treewide: use get_random_u32_below() instead of deprecated function ...