From 3d13f313ce4c34c524ccc37986fe77172f601ff3 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 11 Aug 2020 18:33:47 -0700 Subject: uaccess: add force_uaccess_{begin,end} helpers Add helpers to wrap the get_fs/set_fs magic for undoing any damange done by set_fs(KERNEL_DS). There is no real functional benefit, but this documents the intent of these calls better, and will allow stubbing the functions out easily for kernels builds that do not allow address space overrides in the future. [hch@lst.de: drop two incorrect hunks, fix a commit log typo] Link: http://lkml.kernel.org/r/20200714105505.935079-6-hch@lst.de Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Acked-by: Linus Torvalds Acked-by: Mark Rutland Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven Cc: Nick Hu Cc: Vincent Chen Cc: Paul Walmsley Cc: Palmer Dabbelt Link: http://lkml.kernel.org/r/20200710135706.537715-6-hch@lst.de Signed-off-by: Linus Torvalds --- drivers/firmware/arm_sdei.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c index e7e36aab2386..b4b9ce97f415 100644 --- a/drivers/firmware/arm_sdei.c +++ b/drivers/firmware/arm_sdei.c @@ -1136,15 +1136,14 @@ int sdei_event_handler(struct pt_regs *regs, * access kernel memory. * Do the same here because this doesn't come via the same entry code. */ - orig_addr_limit = get_fs(); - set_fs(USER_DS); + orig_addr_limit = force_uaccess_begin(); err = arg->callback(event_num, regs, arg->callback_arg); if (err) pr_err_ratelimited("event %u on CPU %u failed with error: %d\n", event_num, smp_processor_id(), err); - set_fs(orig_addr_limit); + force_uaccess_end(orig_addr_limit); return err; } -- cgit 1.4.1