kernel/git/next/linux-next.git/drivers/block/sunvdc.c, branch master

sunvdc: fix -EIO issue due to lack of retries

2026-09-10T20:45:59+00:00

John reports that since commit: a11f6ca9aef9 ("sunvdc: Do not spin in an infinite loop when vio_ldc_send() returns EAGAIN") users of Linux inside Solaris ldom see occasional -EIO errors because the request send loop now times out. The current loop does 10 retries, and inside vio_ldc_send() a further 1000 1usec retries are done as well. Even with 10.5 msec of busy loop retries that's apparently not enough to always succeed. Rather than introduce continued busy looping, requeue the request and have the delayed queue kicking retry the request after another 10ms. This obviously isn't ideal, but there's seemingly no way to wait for this type of event. And if 10ms of busy looping was not enough to make progress, then presumably this is an edge condition and we just need to guarantee to make forward progress at some later point in time. That's more suitably done through letting the CPU tend to other work, rather than sitting in a tight loop retrying. [stian: rebased on top of the cookie-unmap fix, without which every requeued attempt leaks LDC map table entries; tested on an UltraSPARC T4 LDOM where the vdc_tx_trigger failure condition was reproduced and absorbed by the requeue with no I/O error] Reported-by: John Paul Adrian Glaubitz Link: https://lore.kernel.org/all/20251006100226.4246-2-glaubitz@physik.fu-berlin.de/ Link: https://lore.kernel.org/all/418310b3-2b77-4534-b2fd-27dcc11e333c@kernel.dk/ Signed-off-by: Stian Halseth Link: https://patch.msgid.link/20260901173947.3292110-3-stian@itx.no Signed-off-by: Jens Axboe

sunvdc: unmap LDC cookies when the descriptor send fails

2026-09-10T20:45:59+00:00

__send_request() maps the request's pages into the LDC channel's map table (ldc_map_sg()), fills in the descriptor and marks it VIO_DESC_READY before ringing the doorbell via __vdc_tx_trigger(). When the trigger fails, the error path only prints a message: the descriptor stays READY and the cookies are never unmapped. The mapping is normally released in vdc_end_one() when the peer completes the descriptor - but a descriptor whose doorbell was never sent will never complete, and since dr->prod is not advanced on failure, the reset path (vdc_requeue_inflight(), which walks [cons, prod)) never visits it either. The map table entries are leaked permanently. Since commit a11f6ca9aef9 ("sunvdc: Do not spin in an infinite loop when vio_ldc_send() returns EAGAIN") trigger failures occur in practice under load, so every resulting I/O error also leaks one request's worth of entries from the fixed-size (8192 entries per channel) map table. Because the allocator hands out contiguous ranges, fragmentation makes large multi-segment requests fail first as the table drains, until ldc_map_sg() fails permanently and the disk is dead until reboot. It also makes any retry-based recovery unusable: requeuing the request on -EAGAIN remaps the pages on every attempt, overwriting desc->cookies and orphaning the previous mapping, so the table drains at the retry rate. This is the memory exhaustion observed when the requeue approach was first tested in October 2025. Roll back on failure: unmap the cookies, mark the descriptor FREE again and clear the request entry. If the trigger failed with -ENOTCONN, __vdc_tx_trigger() has already reset the port, which tears down and reallocates both the dring and the LDC channel including its map table - nothing to roll back, and the stale descriptor must not be touched. Fixes: a11f6ca9aef9 ("sunvdc: Do not spin in an infinite loop when vio_ldc_send() returns EAGAIN") Reported-by: John Paul Adrian Glaubitz Link: https://github.com/sparclinux/issues/issues/2 Signed-off-by: Stian Halseth Link: https://patch.msgid.link/20260901173947.3292110-2-stian@itx.no Signed-off-by: Jens Axboe

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

drivers/block: WQ_PERCPU added to alloc_workqueue users

2025-09-09T15:11:31+00:00

Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. alloc_workqueue() treats all queues as per-CPU by default, while unbound workqueues must opt-in via WQ_UNBOUND. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This patch adds a new WQ_PERCPU flag to explicitly request the use of the per-CPU behavior. Both flags coexist for one release cycle to allow callers to transition their calls. Once migration is complete, WQ_UNBOUND can be removed and unbound will become the implicit default. With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND must now use WQ_PERCPU. All existing users have been updated accordingly. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Jens Axboe

drivers/block: replace use of system_wq with system_percpu_wq

2025-09-09T15:11:31+00:00

block: switch ->getgeo() to struct gendisk

2025-08-13T06:59:29+00:00

Instances are happier that way and it makes more sense anyway - the only part of the result that is related to partition we are given is the start sector, and that has been filled in by the caller. Everything else is a function of the disk. Only one instance (DASD) is ever looking at anything other than bdev->bd_disk and that one is trivial to adjust. Reviewed-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Acked-by: Jens Axboe Signed-off-by: Al Viro

sunvdc: Balance device refcount in vdc_port_mpgroup_check

2025-07-22T16:02:17+00:00

Using device_find_child() to locate a probed virtual-device-port node causes a device refcount imbalance, as device_find_child() internally calls get_device() to increment the device’s reference count before returning its pointer. vdc_port_mpgroup_check() directly returns true upon finding a matching device without releasing the reference via put_device(). We should call put_device() to decrement refcount. As comment of device_find_child() says, 'NOTE: you will need to drop the reference with put_device() after use'. Found by code review. Cc: stable@vger.kernel.org Fixes: 3ee70591d6c4 ("sunvdc: prevent sunvdc panic when mpgroup disk added to guest domain") Signed-off-by: Ma Ke Link: https://lore.kernel.org/r/20250719075856.3447953-1-make24@iscas.ac.cn Signed-off-by: Jens Axboe

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

block: remove unused parameter 'q' parameter in __blk_rq_map_sg()

2025-03-13T11:46:19+00:00

request_queue param is no longer used by blk_rq_map_sg and __blk_rq_map_sg. Remove it. Signed-off-by: Anuj Gupta Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250313035322.243239-1-anuj20.g@samsung.com Signed-off-by: Jens Axboe