David S. Miller 4ca9a23765 sparc64: Guard against flushing openfirmware mappings. ... Based almost entirely upon a patch by Christopher Alexander Tobias Schulze. In commit db64fe0225 ("mm: rewrite vmap layer") lazy VMAP tlb flushing was added to the vmalloc layer. This causes problems on sparc64. Sparc64 has two VMAP mapped regions and they are not contiguous with eachother. First we have the malloc mapping area, then another unrelated region, then the vmalloc region. This "another unrelated region" is where the firmware is mapped. If the lazy TLB flushing logic in the vmalloc code triggers after we've had both a module unload and a vfree or similar, it will pass an address range that goes from somewhere inside the malloc region to somewhere inside the vmalloc region, and thus covering the openfirmware area entirely. The sparc64 kernel learns about openfirmware's dynamic mappings in this region early in the boot, and then services TLB misses in this area. But openfirmware has some locked TLB entries which are not mentioned in those dynamic mappings and we should thus not disturb them. These huge lazy TLB flush ranges causes those openfirmware locked TLB entries to be removed, resulting in all kinds of problems including hard hangs and crashes during reboot/reset. Besides causing problems like this, such huge TLB flush ranges are also incredibly inefficient. A plea has been made with the author of the VMAP lazy TLB flushing code, but for now we'll put a safety guard into our flush_tlb_kernel_range() implementation. Since the implementation has become non-trivial, stop defining it as a macro and instead make it a function in a C source file. Signed-off-by: David S. Miller <davem@davemloft.net>		2014-08-04 20:16:00 -07:00
..
boot	sparc: Fix piggyback with newer binutils.	2012-12-03 11:24:25 -08:00
configs	perf: Remove PERF_COUNTERS config option	2012-04-26 13:52:52 +02:00
crypto	sparc64: fix sparse warnings in aes_glue.c	2014-05-18 19:01:33 -07:00
include	sparc64: Guard against flushing openfirmware mappings.	2014-08-04 20:16:00 -07:00
kernel	sparc: Hook up renameat2 syscall.	2014-07-21 22:27:56 -07:00
lib	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next	2014-06-19 07:50:07 -10:00
math-emu	sparc64: remove cast from output constraints in math asm statements	2014-05-18 19:01:28 -07:00
mm	sparc64: Guard against flushing openfirmware mappings.	2014-08-04 20:16:00 -07:00
net	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2014-06-11 16:02:55 -07:00
oprofile	sparc: using HZ needs an include of linux/param.h	2009-10-05 00:46:08 -07:00
power	sparc64: Hibernation support	2013-03-20 11:06:54 -07:00
prom	sparc64: fix sparse warnings in smp_64.c	2014-05-18 19:01:31 -07:00
Kbuild	sparc64: Add SHA1 driver making use of the 'sha1' instruction.	2012-08-20 15:08:49 -07:00
Kconfig	locking/mutex: Disable optimistic spinning on some architectures	2014-07-16 14:57:07 +02:00
Kconfig.debug	lib: consolidate DEBUG_STACK_USAGE option	2011-05-25 08:39:54 -07:00
Makefile	sparc64: Hibernation support	2013-03-20 11:06:54 -07:00