From: Michał Mirosław <mirq-linux@rere.qmqm.pl> stable inclusion from stable-5.10.80 commit 03f2578153eb09b386ef237be4cb285f3389f8fa bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 0d08e7bf0d0d1a29aff7b16ef516f7415eb1aa05 upstream. Currently __set_fixmap() bails out with a warning when called in early boot from early_iounmap(). Fix it, and while at it, make the comment a bit easier to understand. Cc: <stable@vger.kernel.org> Fixes: b089c31c519c ("ARM: 8667/3: Fix memory attribute inconsistencies when using fixmap") Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- arch/arm/mm/mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 52117aab0942..c9e32610f05e 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -392,9 +392,9 @@ void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) FIXADDR_END); BUG_ON(idx >= __end_of_fixed_addresses); - /* we only support device mappings until pgprot_kernel has been set */ + /* We support only device mappings before pgprot_kernel is set. */ if (WARN_ON(pgprot_val(prot) != pgprot_val(FIXMAP_PAGE_IO) && - pgprot_val(pgprot_kernel) == 0)) + pgprot_val(prot) && pgprot_val(pgprot_kernel) == 0)) return; if (pgprot_val(prot)) -- 2.20.1