mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep

2018-02-25T10:01:21Z

[ Upstream commit 7f6f60a1ba52538c16f26930bfbcfe193d9d746a ] earlyprintk=efi,keep does not work any more with a warning in mm/early_ioremap.c: WARN_ON(system_state != SYSTEM_BOOTING): Boot just hangs because of the earlyprintk within the earlyprintk implementation code itself. This is caused by a new introduced middle state in: 69a78ff226fe ("init: Introduce SYSTEM_SCHEDULING state") early_ioremap() is fine in both SYSTEM_BOOTING and SYSTEM_SCHEDULING states, original condition should be updated accordingly. Signed-off-by: Dave Young Acked-by: Thomas Gleixner Cc: Linus Torvalds Cc: Peter Zijlstra Cc: bp@suse.de Cc: linux-efi@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20171209041610.GA3249@dhcp-128-65.nay.redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

mm: create generic early_ioremap() support

2014-04-07T23:36:15Z

This patch creates a generic implementation of early_ioremap() support based on the existing x86 implementation. early_ioremp() is useful for early boot code which needs to temporarily map I/O or memory regions before normal mapping functions such as ioremap() are available. Some architectures have optional MMU. In the no-MMU case, the remap functions simply return the passed in physical address and the unmap functions do nothing. Signed-off-by: Mark Salter Acked-by: Catalin Marinas Acked-by: H. Peter Anvin Cc: Borislav Petkov Cc: Dave Young Cc: Will Deacon Cc: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kernel.git/mm/early_ioremap.c, branch linux-3.18.y

mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep

mm: create generic early_ioremap() support