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* s390/setup: adjust start_code of init_mm to _textVasily Gorbik2019-08-061-2/+1
| | | | | | | | | | | | | After some investigation it doesn't look like init_mm fields start_code/end_code are used anywhere besides potentially in dump_mm for debugging purposes. Originally the value of 0 for start_code reflected the presence of lowcore and early boot code. But with kaslr in place start_code/end_code range should not span over unoccupied by the code segment memory. So, adjust init_mm start_code to point at the beginning of the code segment like other architectures do it. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* s390: enforce CONFIG_SMPHeiko Carstens2019-06-071-2/+0
| | | | | | | | | | | | | There never have been distributions that shiped with CONFIG_SMP=n for s390. In addition the kernel currently doesn't even compile with CONFIG_SMP=n for s390. Most likely it wouldn't even work, even if we fix the compile error, since nobody tests it, since there is no use case that I can think of. Therefore simply enforce CONFIG_SMP and get rid of some more or less unused code. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/unwind: introduce stack unwind APIMartin Schwidefsky2019-05-021-0/+1
| | | | | | | | | | | | | | | | | | Rework the dump_trace() stack unwinder interface to support different unwinding algorithms. The new interface looks like this: struct unwind_state state; unwind_for_each_frame(&state, task, regs, start_stack) do_something(state.sp, state.ip, state.reliable); The unwind_bc.c file contains the implementation for the classic back-chain unwinder. One positive side effect of the new code is it now handles ftraced functions gracefully. It prints the real name of the return function instead of 'return_to_handler'. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: add support for kernel address space layout randomization (KASLR)Gerald Schaefer2019-04-291-0/+1
| | | | | | | | | | | | This patch adds support for relocating the kernel to a random address. The random kernel offset is obtained from cpacf, using either TRNG, PRNO, or KMC_PRNG, depending on supported MSA level. KERNELOFFSET is added to vmcoreinfo, for crash --kaslr support. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: introduce .dma sectionsGerald Schaefer2019-04-291-0/+9
| | | | | | | | | | | | | | | | | | | | | | | With a relocatable kernel that could reside at any place in memory, code and data that has to stay below 2 GB needs special handling. This patch introduces .dma sections for such text, data and ex_table. The sections will be part of the decompressor kernel, so they will not be relocated and stay below 2 GB. Their location is passed over to the decompressed / relocated kernel via the .boot.preserved.data section. The duald and aste for control register setup also need to stay below 2 GB, so move the setup code from arch/s390/kernel/head64.S to arch/s390/boot/head.S. The duct and linkage_stack could reside above 2 GB, but their content has to be preserved for the decompresed kernel, so they are also moved into the .dma section. The start and end address of the .dma sections is added to vmcoreinfo, for crash support, to help debugging in case the kernel crashed there. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sclp: do not use static sccbsGerald Schaefer2019-04-291-1/+1
| | | | | | | | | | | | | | | | | | | | The sccbs for init/read/sdias/early have to be located below 2 GB, and they are currently defined as a static buffer. With a relocatable kernel that could reside at any place in memory, this will no longer guarantee the location below 2 GB, so use a dynamic GFP_DMA allocation instead. The sclp_early_sccb buffer needs special handling, as it can be used very early, and by both the decompressor and also the decompressed kernel. Therefore, a fixed 4 KB buffer is introduced at 0x11000, the former PARMAREA_END. The new PARMAREA_END is now 0x12000, and it is renamed to HEAD_END, as it is rather the end of head.S and not the end of the parmarea. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/ipl: read IPL report at early bootMartin Schwidefsky2019-04-261-0/+45
| | | | | | | | | | | | | Read the IPL Report block provided by secure-boot, add the entries of the certificate list to the system key ring and print the list of components. PR: Adjust to Vasilys bootdata_preserved patch set. Preserve ipl_cert_list for later use in kexec_file. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Philipp Rudo <prudo@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: report new CPU capabilitiesMartin Schwidefsky2019-04-251-0/+8
| | | | | | | | | | | | Add hardware capability bits and features tags to /proc/cpuinfo for 4 new CPU features: "Vector-Enhancements Facility 2" (tag "vxe2", hwcap 2^15) "Vector-Packed-Decimal-Enhancement Facility" (tag "vxp", hwcap 2^16) "Enhanced-Sort Facility" (tag "sort", hwcap 2^17) "Deflate-Conversion Facility" (tag "dflt", hwcap 2^18) Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/uv: introduce guest side ultravisor codeVasily Gorbik2019-04-101-0/+5
| | | | | | | | | | | | | | | | | | | | The Ultravisor Call Facility (stfle bit 158) defines an API to the Ultravisor (UV calls), a mini hypervisor located at machine level. With help of the Ultravisor, KVM will be able to run "protected" VMs, special VMs whose memory and management data are unavailable to KVM. The protected VMs can also request services from the Ultravisor. The guest api consists of UV calls to share and unshare memory with the kvm hypervisor. To enable this feature support PROTECTED_VIRTUALIZATION_GUEST kconfig option has been introduced. Co-developed-by: Janosch Frank <frankja@de.ibm.com> Signed-off-by: Janosch Frank <frankja@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* treewide: add checks for the return value of memblock_alloc*()Mike Rapoport2019-03-121-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add check for the return value of memblock_alloc*() functions and call panic() in case of error. The panic message repeats the one used by panicing memblock allocators with adjustment of parameters to include only relevant ones. The replacement was mostly automated with semantic patches like the one below with manual massaging of format strings. @@ expression ptr, size, align; @@ ptr = memblock_alloc(size, align); + if (!ptr) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align); [anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type] Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org [rppt@linux.ibm.com: fix format strings for panics after memblock_alloc] Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com [rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails] Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx [akpm@linux-foundation.org: fix xtensa printk warning] Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Reviewed-by: Guo Ren <ren_guo@c-sky.com> [c-sky] Acked-by: Paul Burton <paul.burton@mips.com> [MIPS] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390] Reviewed-by: Juergen Gross <jgross@suse.com> [Xen] Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memblock: memblock_phys_alloc(): don't panicMike Rapoport2019-03-121-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the memblock_phys_alloc() function an inline wrapper for memblock_phys_alloc_range() and update the memblock_phys_alloc() callers to check the returned value and panic in case of error. Link: http://lkml.kernel.org/r/1548057848-15136-8-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Guo Ren <ren_guo@c-sky.com> [c-sky] Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Juergen Gross <jgross@suse.com> [Xen] Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Paul Burton <paul.burton@mips.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 's390-5.1-1' of ↵Linus Torvalds2019-03-051-18/+42
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - A copy of Arnds compat wrapper generation series - Pass information about the KVM guest to the host in form the control program code and the control program version code - Map IOV resources to support PCI physical functions on s390 - Add vector load and store alignment hints to improve performance - Use the "jdd" constraint with gcc 9 to make jump labels working again - Remove amode workaround for old z/VM releases from the DCSS code - Add support for in-kernel performance measurements using the CPU measurement counter facility - Introduce a new PMU device cpum_cf_diag to capture counters and store thenn as event raw data. - Bug fixes and cleanups * tag 's390-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits) Revert "s390/cpum_cf: Add kernel message exaplanations" s390/dasd: fix read device characteristic with CONFIG_VMAP_STACK=y s390/suspend: fix prefix register reset in swsusp_arch_resume s390: warn about clearing als implied facilities s390: allow overriding facilities via command line s390: clean up redundant facilities list setup s390/als: remove duplicated in-place implementation of stfle s390/cio: Use cpa range elsewhere within vfio-ccw s390/cio: Fix vfio-ccw handling of recursive TICs s390: vfio_ap: link the vfio_ap devices to the vfio_ap bus subsystem s390/cpum_cf: Handle EBUSY return code from CPU counter facility reservation s390/cpum_cf: Add kernel message exaplanations s390/cpum_cf_diag: Add support for s390 counter facility diagnostic trace s390/cpum_cf: add ctr_stcctm() function s390/cpum_cf: move common functions into a separate file s390/cpum_cf: introduce kernel_cpumcf_avail() function s390/cpu_mf: replace stcctm5() with the stcctm() function s390/cpu_mf: add store cpu counter multiple instruction support s390/cpum_cf: Add minimal in-kernel interface for counter measurements s390/cpum_cf: introduce kernel_cpumcf_alert() to obtain measurement alerts ...
| * s390/setup: fix boot crash for machine without EDAT-1Martin Schwidefsky2019-02-201-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fix to make WARN work in the early boot code created a problem on older machines without EDAT-1. The setup_lowcore_dat_on function uses the pointer from lowcore_ptr[0] to set the DAT bit in the new PSWs. That does not work if the kernel page table is set up with 4K pages as the prefix address maps to absolute zero. To make this work the PSWs need to be changed with via address 0 in form of the S390_lowcore definition. Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Cornelia Huck <cohuck@redhat.com> Fixes: 94f85ed3e2f8 ("s390/setup: fix early warning messages") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/setup: fix early warning messagesMartin Schwidefsky2019-02-201-9/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The setup_lowcore() function creates a new prefix page for the boot CPU. The PSW mask for the system_call, external interrupt, i/o interrupt and the program check handler have the DAT bit set in this new prefix page. At the time setup_lowcore is called the system still runs without virtual address translation, the paging_init() function creates the kernel page table and loads the CR13 with the kernel ASCE. Any code between setup_lowcore() and the end of paging_init() that has a BUG or WARN statement will create a program check that can not be handled correctly as there is no kernel page table yet. To allow early WARN statements initially setup the lowcore with DAT off and set the DAT bit only after paging_init() has completed. Cc: stable@vger.kernel.org Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390: remove unused including <linux/version.h>YueHaibing2019-02-071-1/+0
| | | | | | | | | | | | | | | | Remove including <linux/version.h> that don't need it. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/setup: remove obsolete #ifdefGerald Schaefer2019-02-071-9/+0
| | | | | | | | | | | | | | | | | | | | The #ifdef CONFIG_DMA_API_DEBUG check in reserve_kernel() is no longer needed, since commit ea535e418c01 ("dma-debug: switch check from _text to _stext") changed the logic in lib/dma-debug.c, so remove it. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/setup: set control program code via diag 318Collin Walling2019-01-281-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The s390x diagnose 318 instruction sets the control program name code (CPNC) and control program version code (CPVC) to provide useful information regarding the OS during debugging. The CPNC is explicitly set to 4 to indicate a Linux/KVM environment. The CPVC is a 7-byte value containing: - 3-byte Linux version code, currently set to 0 - 3-byte unique value, currently set to 0 - 1-byte trailing null Signed-off-by: Collin Walling <walling@linux.ibm.com> Acked-by: Janosch Frank <frankja@linux.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <1544135405-22385-2-git-send-email-walling@linux.ibm.com> [set version code to 0 until the structure is fully defined] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | s390/early: improve machine detectionChristian Borntraeger2019-01-111-0/+2
|/ | | | | | | | | | | | | | Right now the early machine detection code check stsi 3.2.2 for "KVM" and set MACHINE_IS_VM if this is different. As the console detection uses diagnose 8 if MACHINE_IS_VM returns true this will crash Linux early for any non z/VM system that sets a different value than KVM. So instead of assuming z/VM, do not set any of MACHINE_IS_LPAR, MACHINE_IS_VM, or MACHINE_IS_KVM. CC: stable@vger.kernel.org Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* mm: remove include/linux/bootmem.hMike Rapoport2018-10-311-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memblock: remove _virt from APIs returning virtual addressMike Rapoport2018-10-311-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The conversion is done using sed -i 's@memblock_virt_alloc@memblock_alloc@g' \ $(git grep -l memblock_virt_alloc) Link: http://lkml.kernel.org/r/1536927045-23536-8-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memblock: rename memblock_alloc{_nid,_try_nid} to memblock_phys_alloc*Mike Rapoport2018-10-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make it explicit that the caller gets a physical address rather than a virtual one. This will also allow using meblock_alloc prefix for memblock allocations returning virtual address, which is done in the following patches. The conversion is done using the following semantic patch: @@ expression e1, e2, e3; @@ ( - memblock_alloc(e1, e2) + memblock_phys_alloc(e1, e2) | - memblock_alloc_nid(e1, e2, e3) + memblock_phys_alloc_nid(e1, e2, e3) | - memblock_alloc_try_nid(e1, e2, e3) + memblock_phys_alloc_try_nid(e1, e2, e3) ) Link: http://lkml.kernel.org/r/1536927045-23536-7-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390/vmalloc: fix VMALLOC_START calculationMikhail Zaslonko2018-10-111-2/+2
| | | | | | | | | | | | | | | With the introduction of the module area on top of the vmalloc area, the calculation of VMALLOC_START in setup_memory_end() function hasn't been adjusted. As a result we got vmalloc area 2 Gb (MODULES_LEN) smaller than it should be and the preceding vmemmap area got extra memory instead. The patch fixes this calculation error although there were no visible negative effects. Apart from that, change 'tmp' variable to 'vmemmap' in memory_end calculation for better readability. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kasan: add option for 4-level paging supportVasily Gorbik2018-10-091-1/+3
| | | | | | | | | | | By default 3-level paging is used when the kernel is compiled with kasan support. Add 4-level paging option to support systems with more then 3TB of physical memory and to cover 4-level paging specific code with kasan as well. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kasan: use noexec and large pagesVasily Gorbik2018-10-091-0/+1
| | | | | | | | | | | | | | To lower memory footprint and speed up kasan initialisation detect EDAT availability and use large pages if possible. As we know how much memory is needed for initialisation, another simplistic large page allocator is introduced to avoid memory fragmentation. Since facilities list is retrieved anyhow, detect noexec support and adjust pages attributes. Handle noexec kernel option to avoid inconsistent kasan shadow memory pages flags. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kasan: add initialization code and enable itVasily Gorbik2018-10-091-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kasan needs 1/8 of kernel virtual address space to be reserved as the shadow area. And eventually it requires the shadow memory offset to be known at compile time (passed to the compiler when full instrumentation is enabled). Any value picked as the shadow area offset for 3-level paging would eat up identity mapping on 4-level paging (with 1PB shadow area size). So, the kernel sticks to 3-level paging when kasan is enabled. 3TB border is picked as the shadow offset. The memory layout is adjusted so, that physical memory border does not exceed KASAN_SHADOW_START and vmemmap does not go below KASAN_SHADOW_END. Due to the fact that on s390 paging is set up very late and to cover more code with kasan instrumentation, temporary identity mapping and final shadow memory are set up early. The shadow memory mapping is later carried over to init_mm.pgd during paging_init. For the needs of paging structures allocation and shadow memory population a primitive allocator is used, which simply chops off memory blocks from the end of the physical memory. Kasan currenty doesn't track vmemmap and vmalloc areas. Current memory layout (for 3-level paging, 2GB physical memory). ---[ Identity Mapping ]--- 0x0000000000000000-0x0000000000100000 ---[ Kernel Image Start ]--- 0x0000000000100000-0x0000000002b00000 ---[ Kernel Image End ]--- 0x0000000002b00000-0x0000000080000000 2G <- physical memory border 0x0000000080000000-0x0000030000000000 3070G PUD I ---[ Kasan Shadow Start ]--- 0x0000030000000000-0x0000030010000000 256M PMD RW X <- shadow for 2G memory 0x0000030010000000-0x0000037ff0000000 523776M PTE RO NX <- kasan zero ro page 0x0000037ff0000000-0x0000038000000000 256M PMD RW X <- shadow for 2G modules ---[ Kasan Shadow End ]--- 0x0000038000000000-0x000003d100000000 324G PUD I ---[ vmemmap Area ]--- 0x000003d100000000-0x000003e080000000 ---[ vmalloc Area ]--- 0x000003e080000000-0x000003ff80000000 ---[ Modules Area ]--- 0x000003ff80000000-0x0000040000000000 2G Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: move ipl block and cmd line handling to early boot phaseVasily Gorbik2018-10-091-22/+4
| | | | | | | | | | | | | | | | To distinguish zfcpdump case and to be able to parse some of the kernel command line arguments early (e.g. mem=) ipl block retrieval and command line construction code is moved to the early boot phase. "memory_end" is set up correctly respecting "mem=" and hsa_size in case of the zfcpdump. arch/s390/boot/string.c is introduced to provide string handling and command line parsing functions to early boot phase code for the compressed kernel image case. Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/mem_detect: add info source debug printVasily Gorbik2018-10-091-0/+17
| | | | | | | | Print mem_detect info source when memblock=debug is specified. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/mem_detect: move tprot loop to early boot phaseVasily Gorbik2018-10-091-2/+45
| | | | | | | | | | | | | | | Move memory detection to early boot phase. To store online memory regions "struct mem_detect_info" has been introduced together with for_each_mem_detect_block iterator. mem_detect_info is later converted to memblock. Also introduces sclp_early_get_meminfo function to get maximum physical memory and maximum increment number. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: unify stack size definitionsVasily Gorbik2018-10-091-6/+6
| | | | | | | | | | | | Remove STACK_ORDER and STACK_SIZE in favour of identical THREAD_SIZE_ORDER and THREAD_SIZE definitions. THREAD_SIZE and THREAD_SIZE_ORDER naming is misleading since it is used as general kernel stack size information. But both those definitions are used in the common code and throughout architectures specific code, so changing the naming is problematic. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: add support for virtually mapped kernel stacksMartin Schwidefsky2018-10-091-9/+80
| | | | | | | | | | | | | | | | | | | | | With virtually mapped kernel stacks the kernel stack overflow detection is now fault based, every stack has a guard page in the vmalloc space. The panic_stack is renamed to nodat_stack and is used for all function that need to run without DAT, e.g. memcpy_real or do_start_kdump. The main effect is a reduction in the kernel image size as with vmap stacks the old style overflow checking that adds two instructions per function is not needed anymore. Result from bloat-o-meter: add/remove: 20/1 grow/shrink: 13/26854 up/down: 2198/-216240 (-214042) In regard to performance the micro-benchmark for fork has a hit of a few microseconds, allocating 4 pages in vmalloc space is more expensive compare to an order-2 page allocation. But with real workload I could not find a noticeable difference. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/setup: do not reserve the decompressor codeVasily Gorbik2018-06-251-2/+2
| | | | | | | | | | | Introduce PARMAREA_END, and use it for memblock reserve of low memory, which is used for lowcore, kdump data mover code and page buffer, early stack and parmarea. There is no need to reserve an area between PARMAREA_END and the decompressor _ehead. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: add support for IBM z14 Model ZR1Heiko Carstens2018-04-161-0/+1
| | | | | | | | Just add the new machine type number to the two places that matter. Cc: <stable@vger.kernel.org> # v4.14+ Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: correct nospec auto detection init orderMartin Schwidefsky2018-04-111-0/+3
| | | | | | | | | | | | | | | | With CONFIG_EXPOLINE_AUTO=y the call of spectre_v2_auto_early() via early_initcall is done *after* the early_param functions. This overwrites any settings done with the nobp/no_spectre_v2/spectre_v2 parameters. The code patching for the kernel is done after the evaluation of the early parameters but before the early_initcall is done. The end result is a kernel image that is patched correctly but the kernel modules are not. Make sure that the nospec auto detection function is called before the early parameters are evaluated and before the code patching is done. Fixes: 6e179d64126b ("s390: add automatic detection of the spectre defense") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/setup : enable display support for KVM guestFarhan Ali2018-03-181-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | The S390 architecture does not support any graphics hardware, but with the latest support for Virtio GPU in Linux and Virtio GPU emulation in QEMU, it's possible to enable graphics for S390 using the Virtio GPU device. To enable display we need to enable the Linux Virtual Terminal (VT) layer for S390. But the VT subsystem initializes quite early at boot so we need a dummy console driver till the Virtio GPU driver is initialized and we can run the framebuffer console. The framebuffer console over a Virtio GPU device can be run in combination with the serial SCLP console (default on S390). The SCLP console can still be accessed by management applications (eg: via Libvirt's virsh console). Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-Id: <e23b61f4f599ba23881727a1e8880e9d60cc6a48.1519315352.git.alifm@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: unify linker symbols usageVasily Gorbik2018-02-271-10/+10
| | | | | | | | | | | | | Common code defines linker symbols which denote sections start/end in a form of char []. Referencing those symbols as _symbol or &_symbol yields the same result, but "_symbol" form is more widespread across newly written code. Convert s390 specific code to this style. Also removes unused _text symbol definition in boot/compressed/misc.c. Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: introduce execute-trampolines for branchesMartin Schwidefsky2018-02-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and -mfunction_return= compiler options to create a kernel fortified against the specte v2 attack. With CONFIG_EXPOLINE=y all indirect branches will be issued with an execute type instruction. For z10 or newer the EXRL instruction will be used, for older machines the EX instruction. The typical indirect call basr %r14,%r1 is replaced with a PC relative call to a new thunk brasl %r14,__s390x_indirect_jump_r1 The thunk contains the EXRL/EX instruction to the indirect branch __s390x_indirect_jump_r1: exrl 0,0f j . 0: br %r1 The detour via the execute type instruction has a performance impact. To get rid of the detour the new kernel parameter "nospectre_v2" and "spectre_v2=[on,off,auto]" can be used. If the parameter is specified the kernel and module code will be patched at runtime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/alternative: use a copy of the facility bit maskMartin Schwidefsky2018-02-051-1/+3
| | | | | | | | | | To be able to switch off specific CPU alternatives with kernel parameters make a copy of the facility bit mask provided by STFLE and use the copy for the decision to apply an alternative. Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: kernel: add SPDX identifiers to the remaining filesGreg Kroah-Hartman2017-11-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: simplify transactional execution elf hwcap handlingHeiko Carstens2017-11-091-1/+1
| | | | | | | | | | Just use MACHINE_HAS_TE to decide if HWCAP_S390_TE needs to be added to elf_hwcap. Suggested-by: Dan Horák <dan@danny.cz> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/virtio: remove unused header file kvm_virtio.hChristian Borntraeger2017-11-091-1/+0
| | | | | | | | | | With commit 7fb2b2d51244 ("s390/virtio: remove the old KVM virtio transport") the pre-ccw virtio transport for s390 was removed. To complete the removal the uapi header file that contains the related data structures must also be removed. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* s390/nmi: allocation of the extended save areaMartin Schwidefsky2017-10-191-9/+2
| | | | | | | | | | | | The machine check extended save area is needed to store the vector registers and the guarded storage control block when a CPU is interrupted by a machine check. Move the slab cache allocation of the full save area to nmi.c, for early boot use a static __initdata block. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/vdso: move boot_vdso_data to vdso.cMartin Schwidefsky2017-10-181-1/+1
| | | | | | | | The boot_vdso_data variable is related to the vdso code, the magic of the initial vdso area for the early boot and the replacement of it in vdso_init should all be put into vdso.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: introduce CPU alternativesVasily Gorbik2017-10-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Implement CPU alternatives, which allows to optionally patch newer instructions at runtime, based on CPU facilities availability. A new kernel boot parameter "noaltinstr" disables patching. Current implementation is derived from x86 alternatives. Although ideal instructions padding (when altinstr is longer then oldinstr) is added at compile time, and no oldinstr nops optimization has to be done at runtime. Also couple of compile time sanity checks are done: 1. oldinstr and altinstr must be <= 254 bytes long, 2. oldinstr and altinstr must not have an odd length. alternative(oldinstr, altinstr, facility); alternative_2(oldinstr, altinstr1, facility1, altinstr2, facility2); Both compile time and runtime padding consists of either 6/4/2 bytes nop or a jump (brcl) + 2 bytes nop filler if padding is longer then 6 bytes. .altinstructions and .altinstr_replacement sections are part of __init_begin : __init_end region and are freed after initialization. Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/spinlock: introduce spinlock wait queueingMartin Schwidefsky2017-09-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The queued spinlock code for s390 follows the principles of the common code qspinlock implementation but with a few notable differences. The format of the spinlock_t locking word differs, s390 needs to store the logical CPU number of the lock holder in the spinlock_t to be able to use the diagnose 9c directed yield hypervisor call. The inline code sequences for spin_lock and spin_unlock are nice and short. The inline portion of a spin_lock now typically looks like this: lhi %r0,0 # 0 indicates an empty lock l %r1,0x3a0 # CPU number + 1 from lowcore cs %r0,%r1,<some_lock> # lock operation jnz call_wait # on failure call wait function locked: ... call_wait: la %r2,<some_lock> brasl %r14,arch_spin_lock_wait j locked A spin_unlock is as simple as before: lhi %r0,0 sth %r0,2(%r2) # unlock operation After a CPU has queued itself it may not enable interrupts again for the arch_spin_lock_flags() variant. The arch_spin_lock_wait_flags wait function is removed. To improve performance the code implements opportunistic lock stealing. If the wait function finds a spinlock_t that indicates that the lock is free but there are queued waiters, the CPU may steal the lock up to three times without queueing itself. The lock stealing update the steal counter in the lock word to prevent more than 3 steals. The counter is reset at the time the CPU next in the queue successfully takes the lock. While the queued spinlocks improve performance in a system with dedicated CPUs, in a virtualized environment with continuously overcommitted CPUs the queued spinlocks can have a negative effect on performance. This is due to the fact that a queued CPU that is preempted by the hypervisor will block the queue at some point even without holding the lock. With the classic spinlock it does not matter if a CPU is preempted that waits for the lock. Therefore use the queued spinlock code only if the system runs with dedicated CPUs and fall back to classic spinlocks when running with shared CPUs. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/vmcp: make use of contiguous memory allocatorHeiko Carstens2017-08-091-0/+1
| | | | | | | | | | | | | | | | | | | | If memory is fragmented it is unlikely that large order memory allocations succeed. This has been an issue with the vmcp device driver since a long time, since it requires large physical contiguous memory ares for large responses. To hopefully resolve this issue make use of the contiguous memory allocator (cma). This patch adds a vmcp specific vmcp cma area with a default size of 4MB. The size can be changed either via the VMCP_CMA_SIZE config option at compile time or with the "vmcp_cma" kernel parameter (e.g. "vmcp_cma=16m"). For any vmcp response buffers larger than 16k memory from the cma area will be allocated. If such an allocation fails, there is a fallback to the buddy allocator. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390: add support for IBM z14 machinesMartin Schwidefsky2017-07-261-0/+3
| | | | | | | | | | Add detection for machine type 0x3906 and set the ELF platform name to z14. Add the miscellaneous-instruction-extension 2 facility to the list of facilities for z14. And allow to generate code that only runs on a z14 machine. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/time: add support for the TOD clock epoch extensionMartin Schwidefsky2017-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | The TOD epoch extension adds 8 epoch bits to the TOD clock to provide a continuous clock after 2042/09/17. The store-clock-extended (STCKE) instruction will store the epoch index in the first byte of the 16 bytes stored by the instruction. The read_boot_clock64 and the read_presistent_clock64 functions need to take the additional bits into account to give the correct result after 2042/09/17. The clock-comparator register will stay 64 bit wide. The comparison of the clock-comparator with the TOD clock is limited to bytes 1 to 8 of the extended TOD format. To deal with the overflow problem due to an epoch change the clock-comparator sign control in CR0 can be used to switch the comparison of the 64-bit TOD clock with the clock-comparator to a signed comparison. The decision between the signed vs. unsigned clock-comparator comparisons is done at boot time. Only if the TOD clock is in the second half of a 142 year epoch the signed comparison is used. This solves the epoch overflow issue as long as the machine is booted at least once in an epoch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/mm: use new mm defines instead of magic valuesHeiko Carstens2017-07-261-4/+4
| | | | | | Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* kexec: move vmcoreinfo out of the kernel's .bss sectionXunlei Pang2017-07-121-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | As Eric said, "what we need to do is move the variable vmcoreinfo_note out of the kernel's .bss section. And modify the code to regenerate and keep this information in something like the control page. Definitely something like this needs a page all to itself, and ideally far away from any other kernel data structures. I clearly was not watching closely the data someone decided to keep this silly thing in the kernel's .bss section." This patch allocates extra pages for these vmcoreinfo_XXX variables, one advantage is that it enhances some safety of vmcoreinfo, because vmcoreinfo now is kept far away from other kernel data structures. Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Suggested-by: Eric Biederman <ebiederm@xmission.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* s390: add a system call for guarded storageMartin Schwidefsky2017-03-221-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a new system call to enable the use of guarded storage for user space processes. The system call takes two arguments, a command and pointer to a guarded storage control block: s390_guarded_storage(int command, struct gs_cb *gs_cb); The second argument is relevant only for the GS_SET_BC_CB command. The commands in detail: 0 - GS_ENABLE Enable the guarded storage facility for the current task. The initial content of the guarded storage control block will be all zeros. After the enablement the user space code can use load-guarded-storage-controls instruction (LGSC) to load an arbitrary control block. While a task is enabled the kernel will save and restore the current content of the guarded storage registers on context switch. 1 - GS_DISABLE Disables the use of the guarded storage facility for the current task. The kernel will cease to save and restore the content of the guarded storage registers, the task specific content of these registers is lost. 2 - GS_SET_BC_CB Set a broadcast guarded storage control block. This is called per thread and stores a specific guarded storage control block in the task struct of the current task. This control block will be used for the broadcast event GS_BROADCAST. 3 - GS_CLEAR_BC_CB Clears the broadcast guarded storage control block. The guarded- storage control block is removed from the task struct that was established by GS_SET_BC_CB. 4 - GS_BROADCAST Sends a broadcast to all thread siblings of the current task. Every sibling that has established a broadcast guarded storage control block will load this control block and will be enabled for guarded storage. The broadcast guarded storage control block is used up, a second broadcast without a refresh of the stored control block with GS_SET_BC_CB will not have any effect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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