Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

hpet: Fix missing '=' character in the __setup() code of hpet_mmap_enable

Commit '3d035f580699 ("drivers/char/hpet.c: allow user controlled mmap for
user processes")' introduced a new kernel command line parameter hpet_mmap,
that is required to expose the memory map of the HPET registers to
user-space. Unfortunately the kernel command line parameter 'hpet_mmap' is
broken and never takes effect due to missing '=' character in the __setup()
code of hpet_mmap_enable.

Before this patch:

dmesg output with the kernel command line parameter hpet_mmap=1

[ 0.204152] HPET mmap disabled

dmesg output with the kernel command line parameter hpet_mmap=0

[ 0.204192] HPET mmap disabled

After this patch:

dmesg output with the kernel command line parameter hpet_mmap=1

[ 0.203945] HPET mmap enabled

dmesg output with the kernel command line parameter hpet_mmap=0

[ 0.204652] HPET mmap disabled

Fixes: 3d035f580699 ("drivers/char/hpet.c: allow user controlled mmap for user processes")
Signed-off-by: Buland Singh <bsingh@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

authored by

Buland Singh and committed by
Greg Kroah-Hartman
24d48a61 8147760d

+1 -1
+1 -1
drivers/char/hpet.c
··· 377 377 pr_info("HPET mmap %s\n", hpet_mmap_enabled ? "enabled" : "disabled"); 378 378 return 1; 379 379 } 380 - __setup("hpet_mmap", hpet_mmap_enable); 380 + __setup("hpet_mmap=", hpet_mmap_enable); 381 381 382 382 static int hpet_mmap(struct file *file, struct vm_area_struct *vma) 383 383 {