linux.git - Linus' kernel tree

Age	Commit message (Collapse)	Author
2022-07-20	module: Replace kmap() with kmap_local_page()	Fabio M. De Francesco
	kmap() is being deprecated in favor of kmap_local_page(). Two main problems with kmap(): (1) It comes with an overhead as mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). Tasks can be preempted and, when scheduled to run again, the kernel virtual addresses are restored and still valid. kmap_local_page() is faster than kmap() in kernels with HIGHMEM enabled. Since the use of kmap_local_page() in module_gzip_decompress() and in module_xz_decompress() is safe (i.e., it does not break the strict rules of use), it should be preferred over kmap(). Therefore, replace kmap() with kmap_local_page(). Tested on a QEMU/KVM x86_32 VM with 4GB RAM, booting kernels with HIGHMEM64GB enabled. Modules compressed with XZ or GZIP decompress properly. Cc: Matthew Wilcox <willy@infradead.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-04-05	module: Make internal.h and decompress.c more compliant	Aaron Tomlin
	This patch will address the following warning and style violations generated by ./scripts/checkpatch.pl in strict mode: WARNING: Use #include <linux/module.h> instead of <asm/module.h> #10: FILE: kernel/module/internal.h:10: +#include <asm/module.h> CHECK: spaces preferred around that '-' (ctx:VxV) #18: FILE: kernel/module/internal.h:18: +#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1)) CHECK: Please use a blank line after function/struct/union/enum declarations #69: FILE: kernel/module/internal.h:69: +} +static inline void module_decompress_cleanup(struct load_info info) ^ CHECK: extern prototypes should be avoided in .h files #84: FILE: kernel/module/internal.h:84: +extern int mod_verify_sig(const void mod, struct load_info info); WARNING: Missing a blank line after declarations #116: FILE: kernel/module/decompress.c:116: + struct page page = module_get_next_page(info); + if (!page) { WARNING: Missing a blank line after declarations #174: FILE: kernel/module/decompress.c:174: + struct page *page = module_get_next_page(info); + if (!page) { CHECK: Please use a blank line after function/struct/union/enum declarations #258: FILE: kernel/module/decompress.c:258: +} +static struct kobj_attribute module_compression_attr = __ATTR_RO(compression); Note: Fortunately, the multiple-include optimisation found in include/linux/module.h will prevent duplication/or inclusion more than once. Fixes: f314dfea16a0 ("modsign: log module name in the event of an error") Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-04-04	module: Move all into module/	Aaron Tomlin
	No functional changes. This patch moves all module related code into a separate directory, modifies each file name and creates a new Makefile. Note: this effort is in preparation to refactor core module code. Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>