kernel/git/stable/linux.git/arch/s390/mm/cmm.c, branch master

s390: Remove cond_resched() calls

2026-08-05T13:16:54+00:00

Since [1] cond_resched() is a no-op on s390. Remove all calls. [1] commit 7dadeaa6e851 ("sched: Further restrict the preemption modes") Reviewed-by: Vasily Gorbik Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

s390/cmm: Replace sprintf() with scnprintf() for buffer safety

2025-10-21T08:17:20+00:00

Replace sprintf() with scnprintf() in cmm_timeout_handler() to prevent potential buffer overflow. The scnprintf() function ensures we don't write beyond the buffer size and provides safer string formatting. Signed-off-by: Josephine Pfeiffer Signed-off-by: Heiko Carstens

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

treewide: const qualify ctl_tables where applicable

2025-01-28T12:48:37+00:00

Add the const qualifier to all the ctl_tables in the tree except for watchdog_hardlockup_sysctl, memory_allocation_profiling_sysctls, loadpin_sysctl_table and the ones calling register_net_sysctl (./net, drivers/inifiniband dirs). These are special cases as they use a registration function with a non-const qualified ctl_table argument or modify the arrays before passing them on to the registration function. Constifying ctl_table structs will prevent the modification of proc_handler function pointers as the arrays would reside in .rodata. This is made possible after commit 78eb4ea25cd5 ("sysctl: treewide: constify the ctl_table argument of proc_handlers") constified all the proc_handlers. Created this by running an spatch followed by a sed command: Spatch: virtual patch @ depends on !(file in "net") disable optional_qualifier @ identifier table_name != { watchdog_hardlockup_sysctl, iwcm_ctl_table, ucma_ctl_table, memory_allocation_profiling_sysctls, loadpin_sysctl_table }; @@ + const struct ctl_table table_name [] = { ... }; sed: sed --in-place \ -e "s/struct ctl_table .table = &uts_kern/const struct ctl_table *table = \&uts_kern/" \ kernel/utsname_sysctl.c Reviewed-by: Song Liu Acked-by: Steven Rostedt (Google) # for kernel/trace/ Reviewed-by: Martin K. Petersen # SCSI Reviewed-by: Darrick J. Wong # xfs Acked-by: Jani Nikula Acked-by: Corey Minyard Acked-by: Wei Liu Acked-by: Thomas Gleixner Reviewed-by: Bill O'Donnell Acked-by: Baoquan He Acked-by: Ashutosh Dixit Acked-by: Anna Schumaker Signed-off-by: Joel Granados

s390: kernel: convert timeouts to use secs_to_jiffies()

2025-01-13T04:21:01+00:00

Commit b35108a51cf7 ("jiffies: Define secs_to_jiffies()") introduced secs_to_jiffies(). As the values here are a multiple of 1000, use secs_to_jiffies() instead of msecs_to_jiffies to avoid the multiplication. This is converted using scripts/coccinelle/misc/secs_to_jiffies.cocci with the following Coccinelle rules: @@ constant C; @@ - msecs_to_jiffies(C * 1000) + secs_to_jiffies(C) @@ constant C; @@ - msecs_to_jiffies(C * MSEC_PER_SEC) + secs_to_jiffies(C) [agordeev@linux.ibm.com: simplify cmm_set_timer()] Link: https://lkml.kernel.org/r/Z2G1ZPL2cAlQOYlF@li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com Link: https://lkml.kernel.org/r/20241210-converge-secs-to-jiffies-v3-4-ddfefd7e9f2a@linux.microsoft.com Signed-off-by: Easwar Hariharan Signed-off-by: Alexander Gordeev Acked-by: Alexander Gordeev Cc: Andrew Lunn Cc: Anna-Maria Behnsen Cc: Catalin Marinas Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Daniel Mack Cc: David Airlie Cc: David S. Miller Cc: Dick Kennedy Cc: Eric Dumazet Cc: Florian Fainelli Cc: Greg Kroah-Hartman Cc: Haojian Zhuang Cc: Heiko Carstens Cc: Ilya Dryomov Cc: Jack Wang Cc: Jakub Kicinski Cc: James Bottomley Cc: James Smart Cc: Jaroslav Kysela Cc: Jeff Johnson Cc: Jeff Johnson Cc: Jens Axboe Cc: Jeroen de Borst Cc: Jiri Kosina Cc: Joe Lawrence Cc: Johan Hedberg Cc: Josh Poimboeuf Cc: Jozsef Kadlecsik Cc: Julia Lawall Cc: Kalle Valo Cc: Louis Peens Cc: Lucas De Marchi Cc: Luiz Augusto von Dentz Cc: Maarten Lankhorst Cc: Madhavan Srinivasan Cc: Marcel Holtmann Cc: Martin K. Petersen Cc: Maxime Ripard Cc: Michael Ellerman Cc: Miroslav Benes Cc: Naveen N Rao Cc: Nicholas Piggin Cc: Nicolas Palix Cc: Oded Gabbay Cc: Ofir Bitton Cc: Pablo Neira Ayuso Cc: Paolo Abeni Cc: Petr Mladek Cc: Praveen Kaligineedi Cc: Ray Jui Cc: Robert Jarzmik Cc: Rodrigo Vivi Cc: Roger Pau Monné Cc: Russell King Cc: Scott Branden Cc: Shailend Chand Cc: Simona Vetter Cc: Simon Horman Cc: Sven Schnelle Cc: Takashi Iwai Cc: Thomas Hellström Cc: Thomas Zimmermann Cc: Vasily Gorbik Cc: Xiubo Li Signed-off-by: Andrew Morton

s390/mm: Add cond_resched() to cmm_alloc/free_pages()

2024-09-05T13:17:23+00:00

Adding/removing large amount of pages at once to/from the CMM balloon can result in rcu_sched stalls or workqueue lockups, because of busy looping w/o cond_resched(). Prevent this by adding a cond_resched(). cmm_free_pages() holds a spin_lock while looping, so it cannot be added directly to the existing loop. Instead, introduce a wrapper function that operates on maximum 256 pages at once, and add it there. Signed-off-by: Gerald Schaefer Reviewed-by: Heiko Carstens Signed-off-by: Heiko Carstens

sysctl: treewide: constify the ctl_table argument of proc_handlers

2024-07-24T18:59:29+00:00

const qualify the struct ctl_table argument in the proc_handler function signatures. This is a prerequisite to moving the static ctl_table structs into .rodata data which will ensure that proc_handler function pointers cannot be modified. This patch has been generated by the following coccinelle script: ``` virtual patch @r1@ identifier ctl, write, buffer, lenp, ppos; identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)"; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos); @r2@ identifier func, ctl, write, buffer, lenp, ppos; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos) { ... } @r3@ identifier func; @@ int func( - struct ctl_table * + const struct ctl_table * ,int , void *, size_t *, loff_t *); @r4@ identifier func, ctl; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int , void *, size_t *, loff_t *); @r5@ identifier func, write, buffer, lenp, ppos; @@ int func( - struct ctl_table * + const struct ctl_table * ,int write, void *buffer, size_t *lenp, loff_t *ppos); ``` * Code formatting was adjusted in xfs_sysctl.c to comply with code conventions. The xfs_stats_clear_proc_handler, xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where adjusted. * The ctl_table argument in proc_watchdog_common was const qualified. This is called from a proc_handler itself and is calling back into another proc_handler, making it necessary to change it as part of the proc_handler migration. Co-developed-by: Thomas Weißschuh Signed-off-by: Thomas Weißschuh Co-developed-by: Joel Granados Signed-off-by: Joel Granados

s390/mm: Add missing MODULE_DESCRIPTION() macro

2024-06-28T12:52:31+00:00

With ARCH=s390, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in arch/s390/mm/cmm.o Add the missing invocation of the MODULE_DESCRIPTION() macro. Acked-by: Heiko Carstens Signed-off-by: Jeff Johnson Link: https://lore.kernel.org/r/20240615-md-s390-arch-s390-mm-v1-1-a360eed8c7c3@quicinc.com Signed-off-by: Vasily Gorbik Signed-off-by: Alexander Gordeev

S390: Remove now superfluous sentinel elem from ctl_table arrays

2023-10-10T22:22:02+00:00

This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove the sentinel element from appldata_table, s390dbf_table, topology_ctl_table, cmm_table and page_table_sysctl. Reduced the memory allocation in appldata_register_ops by 1 effectively removing the sentinel from ops->ctl_table. This removal is safe because register_sysctl_sz and register_sysctl use the array size in addition to checking for the sentinel. Tested-by: Alexander Gordeev Acked-by: Heiko Carstens Signed-off-by: Joel Granados Signed-off-by: Luis Chamberlain

s390/mm: make virt_to_pfn() a static inline

2023-08-16T13:13:03+00:00

Making virt_to_pfn() a static inline taking a strongly typed (const void *) makes the contract of a passing a pointer of that type to the function explicit and exposes any misuse of the macro virt_to_pfn() acting polymorphic and accepting many types such as (void *), (unitptr_t) or (unsigned long) as arguments without warnings. For symmetry do the same with pfn_to_virt() reflecting the current layout in asm-generic/page.h. Doing this reveals a number of offenders in the arch code and the S390-specific drivers, so just bite the bullet and fix up all of those as well. Signed-off-by: Linus Walleij Reviewed-by: Alexander Gordeev Link: https://lore.kernel.org/r/20230812-virt-to-phys-s390-v2-1-6c40f31fe36f@linaro.org Signed-off-by: Heiko Carstens