lwn.git/arch/s390/kernel/setup.c, branch v4.3-rc3

s390/setup: fix novx parameter

2015-08-19T08:40:04+00:00

The novx parameter disables the vector facility but the HWCAP_S390_VXRS bit in the ELf hardware capabilies is always set if the machine has the vector facility. If the user space program uses the "vx" string in the features field of /proc/cpuinfo to utilize vector instruction it will crash if the novx kernel paramter is set. Convert setup_hwcaps to an arch_initcall and use MACHINE_HAS_VX to decide if the HWCAPS_S390_VXRS bit needs to be set. Cc: stable@vger.kernel.org # 3.18+ Reported-by: Ulrich Weigand Reviewed-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/numa: add core infrastructure

2015-08-03T16:40:25+00:00

Enable core NUMA support for s390 and add one simple default mode "plain" that creates one single NUMA node. This patch contains several changes from Michael Holzheu. Signed-off-by: Philipp Hachtmann Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390/module: enable generic CPU feature modalias using s390 ELF hwcaps

2015-07-22T07:58:02+00:00

Add support for the generic CPU feature modalias implementation that wires up optional CPU features to udev-based module autoprobing. The file provides definitions to map CPU features to s390 ELF hardware capabilities. Signed-off-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky

revert "s390/mm: make hugepages_supported a boot time decision"

2015-07-17T23:39:52+00:00

Heiko noticed that the current check for hugepage support on s390 is a little bit too harsh as systems which do not support will crash. The reason is that pageblock_order can now get negative when we set HPAGE_SHIFT to 0. To avoid all this and to avoid opening another can of worms with enabling HUGETLB_PAGE_SIZE_VARIABLE I think it would be best to simply allow architectures to define their own hugepages_supported(). Revert bea41197ead3 ("s390/mm: make hugepages_supported a boot time decision") in preparation. Signed-off-by: Dominik Dingel Acked-by: Martin Schwidefsky Cc: Heiko Carstens Cc: Christian Borntraeger Cc: Michael Holzheu Cc: Gerald Schaefer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2015-07-01T04:44:14+00:00

Pull more s390 updates from Martin Schwidefsky: "There is one larger patch for the AP bus code to make it work with the longer reset periods of the latest crypto cards. A new default configuration, a naming cleanup for SMP and a few fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/kdump: fix compile for !SMP s390/kdump: fix nosmt kernel parameter s390: new default configuration s390/smp: cleanup core vs. cpu in the SCLP interface s390/smp: fix sigp cpu detection loop s390/zcrypt: Fixed reset and interrupt handling of AP queues s390/kdump: fix REGSET_VX_LOW vector register ELF notes s390/bpf: Fix backward jumps

s390/mm: make hugepages_supported a boot time decision

2015-06-26T00:00:35+00:00

There is a potential bug with KVM and hugetlbfs if the hardware does not support hugepages (EDAT1). We fix this by making EDAT1 a hard requirement for hugepages and therefore removing and simplifying code. As s390, with the sw-emulated hugepages, was the only user of arch_prepare/release_hugepage I also removed theses calls from common and other architecture code. This patch (of 5): By dropping support for hugepages on machines which do not have the hardware feature EDAT1, we fix a potential s390 KVM bug. The bug would happen if a guest is backed by hugetlbfs (not supported currently), but does not get pagetables with PGSTE. This would lead to random memory overwrites. Signed-off-by: Dominik Dingel Acked-by: Martin Schwidefsky Cc: Heiko Carstens Cc: Christian Borntraeger Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

s390/kdump: fix nosmt kernel parameter

2015-06-25T07:39:26+00:00

It turned out that SIGP set-multi-threading can only be done once. Therefore switching to a different MT level after switching to sclp.mtid_prev in the dump case fails. As a symptom specifying the "nosmt" parameter currently fails for the kdump kernel and the kernel starts with multi-threading enabled. So fix this and issue diag 308 subcode 1 call after collecting the CPU states for the dump. Also enhance the diag308_reset() function to be usable also with enabled lowcore protection and prefix register != 0. After the reset it is possible to switch the MT level again. We have to do the reset very early in order not to kill the already initialized console. Therefore instead of kmalloc() the corresponding memblock functions have to be used. To avoid copying the sclp cpu code into sclp_early, we now use the simple sigp loop method for CPU detection. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky

s390/setup: fix DMA_API_DEBUG warnings

2015-06-18T13:45:46+00:00

Addresses from the usable space in [_ehead, _stext] lead to false positives in DMA_API_DEBUG code (which will complain when an address is in [_text, _etext]). Avoid these warnings by not using that memory in case of CONFIG_DMA_API_DEBUG=y. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky

s390/sclp: unify basic sclp access by exposing "struct sclp"

2015-05-13T07:58:17+00:00

Let's unify basic access to sclp fields by storing the data in an external struct in asm/sclp.h. The values can now directly be accessed by other components, so there is no need for most accessor functions and external variables anymore. The mtid, mtid_max and facility part will be cleaned up separately. Acked-by: Martin Schwidefsky Signed-off-by: David Hildenbrand Signed-off-by: Martin Schwidefsky

s390: remove 31 bit support

2015-03-25T10:49:33+00:00

Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky