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2018-02-22s390: fix handling of -1 in set{,fs}[gu]id16 syscallsEugene Syromiatnikov1-4/+4
commit 6dd0d2d22aa363fec075cb2577ba273ac8462e94 upstream. For some reason, the implementation of some 16-bit ID system calls (namely, setuid16/setgid16 and setfsuid16/setfsgid16) used type cast instead of low2highgid/low2highuid macros for converting [GU]IDs, which led to incorrect handling of value of -1 (which ought to be considered invalid). Discovered by strace test suite. Cc: stable@vger.kernel.org Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10kernel: make groups_sort calling a responsibility group_info allocatorsThiago Rafael Becker1-0/+1
commit bdcf0a423ea1c40bbb40e7ee483b50fc8aa3d758 upstream. In testing, we found that nfsd threads may call set_groups in parallel for the same entry cached in auth.unix.gid, racing in the call of groups_sort, corrupting the groups for that entry and leading to permission denials for the client. This patch: - Make groups_sort globally visible. - Move the call to groups_sort to the modifiers of group_info - Remove the call to groups_sort from set_groups Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com Signed-off-by: Thiago Rafael Becker <thiago.becker@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: NeilBrown <neilb@suse.com> Acked-by: "J. Bruce Fields" <bfields@fieldses.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-16s390: fix compat system call tableHeiko Carstens1-3/+3
commit e779498df587dd2189b30fe5b9245aefab870eb8 upstream. When wiring up the socket system calls the compat entries were incorrectly set. Not all of them point to the corresponding compat wrapper functions, which clear the upper 33 bits of user space pointers, like it is required. Fixes: 977108f89c989 ("s390: wire up separate socketcalls system calls") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09s390/runtime instrumentation: simplify task exit handlingHeiko Carstens2-16/+16
commit 8d9047f8b967ce6181fd824ae922978e1b055cc0 upstream. Free data structures required for runtime instrumentation from arch_release_task_struct(). This allows to simplify the code a bit, and also makes the semantics a bit easier: arch_release_task_struct() is never called from the task that is being removed. In addition this allows to get rid of exit_thread() in a later patch. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30s390/disassembler: increase show_code buffer sizeVasily Gorbik1-2/+2
commit b192571d1ae375e0bbe0aa3ccfa1a3c3704454b9 upstream. Current buffer size of 64 is too small. objdump shows that there are instructions which would require up to 75 bytes buffer (with current formating). 128 bytes "ought to be enough for anybody". Also replaces 8 spaces with a single tab to reduce the memory footprint. Fixes the following KASAN finding: BUG: KASAN: stack-out-of-bounds in number+0x3fe/0x538 Write of size 1 at addr 000000005a4a75a0 by task bash/1282 CPU: 1 PID: 1282 Comm: bash Not tainted 4.14.0+ #215 Hardware name: IBM 2964 N96 702 (z/VM 6.4.0) Call Trace: ([<000000000011eeb6>] show_stack+0x56/0x88) [<0000000000e1ce1a>] dump_stack+0x15a/0x1b0 [<00000000004e2994>] print_address_description+0xf4/0x288 [<00000000004e2cf2>] kasan_report+0x13a/0x230 [<0000000000e38ae6>] number+0x3fe/0x538 [<0000000000e3dfe4>] vsnprintf+0x194/0x948 [<0000000000e3ea42>] sprintf+0xa2/0xb8 [<00000000001198dc>] print_insn+0x374/0x500 [<0000000000119346>] show_code+0x4ee/0x538 [<000000000011f234>] show_registers+0x34c/0x388 [<000000000011f2ae>] show_regs+0x3e/0xa8 [<000000000011f502>] die+0x1ea/0x2e8 [<0000000000138f0e>] do_no_context+0x106/0x168 [<0000000000139a1a>] do_protection_exception+0x4da/0x7d0 [<0000000000e55914>] pgm_check_handler+0x16c/0x1c0 [<000000000090639e>] sysrq_handle_crash+0x46/0x58 ([<0000000000000007>] 0x7) [<00000000009073fa>] __handle_sysrq+0x102/0x218 [<0000000000907c06>] write_sysrq_trigger+0xd6/0x100 [<000000000061d67a>] proc_reg_write+0xb2/0x128 [<0000000000520be6>] __vfs_write+0xee/0x368 [<0000000000521222>] vfs_write+0x21a/0x278 [<000000000052156a>] SyS_write+0xda/0x178 [<0000000000e555cc>] system_call+0xc4/0x270 The buggy address belongs to the page: page:000003d1016929c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x0() raw: 0000000000000000 0000000000000000 0000000000000000 ffffffff00000000 raw: 0000000000000100 0000000000000200 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: 000000005a4a7480: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 000000005a4a7500: 00 00 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 >000000005a4a7580: 00 00 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 ^ 000000005a4a7600: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f8 f8 000000005a4a7680: f2 f2 f2 f2 f2 f2 f8 f8 f2 f2 f3 f3 f3 f3 00 00 ================================================================== Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30s390/disassembler: add missing end marker for e7 tableHeiko Carstens1-0/+1
commit 5c50538752af7968f53924b22dede8ed4ce4cb3b upstream. The e7 opcode table does not have an end marker. Hence when trying to find an unknown e7 instruction the code will access memory behind the table until it finds something that matches the opcode, or the kernel crashes, whatever comes first. This affects not only the in-kernel disassembler but also uprobes and kprobes which refuse to set a probe on unknown instructions, and therefore search the opcode tables to figure out if instructions are known or not. Fixes: 3585cb0280654 ("s390/disassembler: add vector instructions") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30s390/runtime instrumention: fix possible memory corruptionHeiko Carstens1-2/+2
commit d6e646ad7cfa7034d280459b2b2546288f247144 upstream. For PREEMPT enabled kernels the runtime instrumentation (RI) code contains a possible use-after-free bug. If a task that makes use of RI exits, it will execute do_exit() while still enabled for preemption. That function will call exit_thread_runtime_instr() via exit_thread(). If exit_thread_runtime_instr() gets preempted after the RI control block of the task has been freed but before the pointer to it is set to NULL, then save_ri_cb(), called from switch_to(), will write to already freed memory. Avoid this and simply disable preemption while freeing the control block and setting the pointer to NULL. Fixes: e4b8b3f33fca ("s390: add support for runtime instrumentation") Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30s390: fix transactional execution control register handlingHeiko Carstens2-1/+4
commit a1c5befc1c24eb9c1ee83f711e0f21ee79cbb556 upstream. Dan Horák reported the following crash related to transactional execution: User process fault: interruption code 0013 ilc:3 in libpthread-2.26.so[3ff93c00000+1b000] CPU: 2 PID: 1 Comm: /init Not tainted 4.13.4-300.fc27.s390x #1 Hardware name: IBM 2827 H43 400 (z/VM 6.4.0) task: 00000000fafc8000 task.stack: 00000000fafc4000 User PSW : 0705200180000000 000003ff93c14e70 R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:1 AS:0 CC:2 PM:0 RI:0 EA:3 User GPRS: 0000000000000077 000003ff00000000 000003ff93144d48 000003ff93144d5e 0000000000000000 0000000000000002 0000000000000000 000003ff00000000 0000000000000000 0000000000000418 0000000000000000 000003ffcc9fe770 000003ff93d28f50 000003ff9310acf0 000003ff92b0319a 000003ffcc9fe6d0 User Code: 000003ff93c14e62: 60e0b030 std %f14,48(%r11) 000003ff93c14e66: 60f0b038 std %f15,56(%r11) #000003ff93c14e6a: e5600000ff0e tbegin 0,65294 >000003ff93c14e70: a7740006 brc 7,3ff93c14e7c 000003ff93c14e74: a7080000 lhi %r0,0 000003ff93c14e78: a7f40023 brc 15,3ff93c14ebe 000003ff93c14e7c: b2220000 ipm %r0 000003ff93c14e80: 8800001c srl %r0,28 There are several bugs with control register handling with respect to transactional execution: - on task switch update_per_regs() is only called if the next task has an mm (is not a kernel thread). This however is incorrect. This breaks e.g. for user mode helper handling, where the kernel creates a kernel thread and then execve's a user space program. Control register contents related to transactional execution won't be updated on execve. If the previous task ran with transactional execution disabled then the new task will also run with transactional execution disabled, which is incorrect. Therefore call update_per_regs() unconditionally within switch_to(). - on startup the transactional execution facility is not enabled for the idle thread. This is not really a bug, but an inconsistency to other facilities. Therefore enable the facility if it is available. - on fork the new thread's per_flags field is not cleared. This means that a child process inherits the PER_FLAG_NO_TE flag. This flag can be set with a ptrace request to disable transactional execution for the current process. It should not be inherited by new child processes in order to be consistent with the handling of all other PER related debugging options. Therefore clear the per_flags field in copy_thread_tls(). Reported-and-tested-by: Dan Horák <dan@danny.cz> Fixes: d35339a42dd1 ("s390: add support for transactional memory") Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17s390/kvm: do not rely on the ILC on kvm host protection faulsChristian Borntraeger1-6/+13
commit c0e7bb38c07cbd8269549ee0a0566021a3c729de upstream. For most cases a protection exception in the host (e.g. copy on write or dirty tracking) on the sie instruction will indicate an instruction length of 4. Turns out that there are some corner cases (e.g. runtime instrumentation) where this is not necessarily true and the ILC is unpredictable. Let's replace our 4 byte rewind_pad with 3 byte nops to prepare for all possible ILCs. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25s390/cputime: fix incorrect system timeMartin Schwidefsky1-3/+18
commit 07a63cbe8bcb6ba72fb989dcab1ec55ec6c36c7e upstream. git commit c5328901aa1db134 "[S390] entry[64].S improvements" removed the update of the exit_timer lowcore field from the critical section cleanup of the .Lsysc_restore/.Lsysc_done and .Lio_restore/.Lio_done blocks. If the PSW is updated by the critical section cleanup to point to user space again, the interrupt entry code will do a vtime calculation after the cleanup completed with an exit_timer value which has *not* been updated. Due to this incorrect system time deltas are calculated. If an interrupt occured with an old PSW between .Lsysc_restore/.Lsysc_done or .Lio_restore/.Lio_done update __LC_EXIT_TIMER with the system entry time of the interrupt. Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25s390/kdump: Add final noteMichael Holzheu1-0/+15
commit dcc00b79fc3d076832f7240de8870f492629b171 upstream. Since linux v3.14 with commit 38dfac843cb6d7be1 ("vmcore: prevent PT_NOTE p_memsz overflow during header update") on s390 we get the following message in the kdump kernel: Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x6b6b6b6b, n_descsz=0x6b6b6b6b The reason for this is that we don't create a final zero note in the ELF header which the proc/vmcore code uses to find out the end of the notes section (see also kernel/kexec_core.c:final_note()). It still worked on s390 by chance because we (most of the time?) have the byte pattern 0x6b6b6b6b after the notes section which also makes the notes parsing code stop in update_note_header_size_elf64() because 0x6b6b6b6b is interpreded as note size: if ((real_sz + sz) > max_sz) { pr_warn("Warning: Exceeded p_memsz, dropping P ...); break; } So fix this and add the missing final note to the ELF header. We don't have to adjust the memory size for ELF header ("alloc_size") because the new ELF note still fits into the 0x1000 base memory. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-18s390/kdump: Use "LINUX" ELF note name instead of "CORE"Michael Holzheu1-8/+10
commit a4a81d8eebdc1d209d034f62a082a5131e4242b5 upstream. In binutils/libbfd (bfd/elf.c) it is enforced that all s390 specific ELF notes like e.g. NT_S390_PREFIX or NT_S390_CTRS have "LINUX" specified as note name. Otherwise the notes are ignored. For /proc/vmcore we currently use "CORE" for these notes. Up to now this has not been a real problem because the dump analysis tool "crash" does not check the note name. But it will break all programs that use libbfd for processing ELF notes. So fix this and use "LINUX" for all s390 specific notes to comply with libbfd. Reported-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-15s390: use correct input data address for setup_randomnessHeiko Carstens1-1/+1
commit 4920e3cf77347d7d7373552d4839e8d832321313 upstream. The current implementation of setup_randomness uses the stack address and therefore the pointer to the SYSIB 3.2.2 block as input data address. Furthermore the length of the input data is the number of virtual-machine description blocks which is typically one. This means that typically a single zero byte is fed to add_device_randomness. Fix both of these and use the address of the first virtual machine description block as input data address and also use the correct length. Fixes: bcfcbb6bae64 ("s390: add system information as device randomness") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-15s390: make setup_randomness workHeiko Carstens1-3/+3
commit da8fd820f389a0e29080b14c61bf5cf1d8ef5ca1 upstream. Commit bcfcbb6bae64 ("s390: add system information as device randomness") intended to add some virtual machine specific information to the randomness pool. Unfortunately it uses the page allocator before it is ready to use. In result the page allocator always returns NULL and the setup_randomness function never adds anything to the randomness pool. To fix this use memblock_alloc and memblock_free instead. Fixes: bcfcbb6bae64 ("s390: add system information as device randomness") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-01s390/ptrace: Preserve previous registers for short regset writeMartin Schwidefsky1-0/+8
commit 9dce990d2cf57b5ed4e71a9cdbd7eae4335111ff upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. convert_vx_to_fp() is adapted to handle only a specified number of registers rather than unconditionally handling all of them: other callers of this function are adapted appropriately. Based on an initial patch by Dave Martin. Reported-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-16Revert "s390/kdump: Clear subchannel ID to signal non-CCW/SCSI IPL"Michael Holzheu1-7/+0
commit 5419447e2142d6ed68c9f5c1a28630b3a290a845 upstream. This reverts commit 852ffd0f4e23248b47531058e531066a988434b5. There are use cases where an intermediate boot kernel (1) uses kexec to boot the final production kernel (2). For this scenario we should provide the original boot information to the production kernel (2). Therefore clearing the boot information during kexec() should not be done. Reported-by: Steffen Maier <maier@linux.vnet.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12s390/cpumf: add missing lpp magic initializationHeiko Carstens1-0/+1
commit 8f100bb1ff27873dd71f636da670e503b9ade3c6 upstream. Add the missing lpp magic initialization for cpu 0. Without this all samples on cpu 0 do not have the most significant bit set in the program parameter field, which we use to distinguish between guest and host samples if the pid is also 0. We did initialize the lpp magic in the absolute zero lowcore but forgot that when switching to the allocated lowcore on cpu 0 only. Reported-by: Shu Juan Zhang <zhshuj@cn.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12s390: fix floating pointer register corruption (again)Martin Schwidefsky1-104/+2
commit e370e4769463a65dcf8806fa26d2874e0542ac41 upstream. There is a tricky interaction between the machine check handler and the critical sections of load_fpu_regs and save_fpu_regs functions. If the machine check interrupts one of the two functions the critical section cleanup will complete the function before the machine check handler s390_do_machine_check is called. Trouble is that the machine check handler needs to validate the floating point registers *before* and not *after* the completion of load_fpu_regs/save_fpu_regs. The simplest solution is to rewind the PSW to the start of the load_fpu_regs/save_fpu_regs and retry the function after the return from the machine check handler. Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12s390/cpumf: Fix lpp detectionChristian Borntraeger1-1/+1
commit 7a76aa95f6f6682db5629449d763251d1c9f8c4e upstream. we have to check bit 40 of the facility list before issuing LPP and not bit 48. Otherwise a guest running on a system with "The decimal-floating-point zoned-conversion facility" and without the "The set-program-parameters facility" might crash on an lpp instruction. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03s390/compat: correct restore of high gprs on signal returnMartin Schwidefsky1-1/+1
commit 342300cc9cd3428bc6bfe5809bfcc1b9a0f06702 upstream. git commit 8070361799ae1e3f4ef347bd10f0a508ac10acfb "s390: add support for vector extension" broke 31-bit compat processes in regard to signal handling. The restore_sigregs_ext32() function is used to restore the additional elements from the user space signal frame. Among the additional elements are the upper registers halves for 64-bit register support for 31-bit processes. The copy_from_user that is used to retrieve the high-gprs array from the user stack uses an incorrect length, 8 bytes instead of 64 bytes. This causes incorrect upper register halves to get loaded. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-03s390/kvm: remove dependency on struct save_area definitionMartin Schwidefsky1-0/+1
commit d9a3a09af54d01ab8b0c320580f4f95328d4a7ac upstream. Replace the offsets based on the struct area_area with the offset constants from asm-offsets.c based on the struct _lowcore. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-18s390/dis: Fix handling of format specifiersMichael Holzheu1-5/+12
The print_insn() function returns strings like "lghi %r1,0". To escape the '%' character in sprintf() a second '%' is used. For example "lghi %%r1,0" is converted into "lghi %r1,0". After print_insn() the output string is passed to printk(). Because format specifiers like "%r" or "%f" are ignored by printk() this works by chance most of the time. But for instructions with control registers like "lctl %c6,%c6,780" this fails because printk() interprets "%c" as character format specifier. Fix this problem and escape the '%' characters twice. For example "lctl %%%%c6,%%%%c6,780" is then converted by sprintf() into "lctl %%c6,%%c6,780" and by printk() into "lctl %c6,%c6,780". Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16s390: remove SALIPL loaderHeiko Carstens1-79/+8
There is no known user, therefore remove the code. Acked-by: Rob Van Der Heij <robvdheij@nl.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16s390: wire up mlock2 system callHeiko Carstens2-0/+2
Passes mlock2-tests test case in 64 bit and compat mode. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16s390: remove g5 elf platform supportHeiko Carstens1-3/+0
Remove dead code, since this could only happen on a 31 bit machine where the kernel wouldn't IPL. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-16s390: avoid cache aliasing under z/VM and KVMMartin Schwidefsky1-5/+1
commit 1f6b83e5e4d3 ("s390: avoid z13 cache aliasing") checks for the machine type to optimize address space randomization and zero page allocation to avoid cache aliases. This check might fail under a hypervisor with migration support. z/VMs "Single System Image and Live Guest Relocation" facility will "fake" the machine type of the oldest system in the group. For example in a group of zEC12 and Z13 the guest appears to run on a zEC12 (architecture fencing within the relocation domain) Remove the machine type detection and always use cache aliasing rules that are known to work for all machines. These are the z13 aliasing rules. Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-12s390/sclp: _sclp_wait_int(): retain full PSW maskSascha Silbe1-1/+1
There's no reason to clear all PSW mask bits other than the addressing mode bits. Just use the previous PSW mask as-is. Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11s390: add support for ipl devices in subchannel sets > 0Sebastian Ott1-11/+37
Allow to ipl from CCW based devices residing in any subchannel set. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-11s390/ipl: fix out of bounds access in scpdata_writeSebastian Ott1-12/+5
The input buffer in reipl_fcp_scpdata_write is accessed out of bounds when an offset is specified. The problem is that the offset refers to the data we should write to and not to the buffer we read from. So instead of memcpy(scp_data, buf + off, count); we could just do memcpy(scp_data + off, buf, count); However we not only modify the data but also store its length. For this to work we'd need to remember a state per open FH. Since that's not possible with sysfs callbacks let's just fail when an offset is specified. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Acked-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09s390/diag: add a s390 prefix to the diagnose trace pointMartin Schwidefsky2-5/+5
Documentation/trace/tracepoints.txt states that the naming scheme for tracepoints is "subsys_event" to avoid collisions. Rename the 'diagnose' tracepoint to 's390_diagnose'. Reported-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-09s390/head: fix error message on unsupported hardwareSascha Silbe1-4/+4
startup calls the C function _sclp_print_early() if the machine we're running on is not supported by the kernel. sclp.c is getting built with -m64, so _sclp_print_early() expects the zSeries ELF ABI to be used. We previously called _sclp_print_early() using the S/390 ELF ABI, with a stack frame size of 96 bytes and while being in 31-bit address mode. This caused _sclp_wait_int() (called indirectly from _sclp_print_early()) to jump to an undefined address. While _sclp_wait_int() contained some code to deal with being called in 31-bit addressing mode, it didn't quite work. While fixing this is possible, the code would still only work by chance and could break any time. Ensure compliance with the zSeries ELF ABI by switching to 64-bit addressing mode early and using a minimum stack frame size of 160 bytes. Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-04Merge branch 'for-linus' of ↵Linus Torvalds26-547/+608
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "There is only one new feature in this pull for the 4.4 merge window, most of it is small enhancements, cleanup and bug fixes: - Add the s390 backend for the software dirty bit tracking. This adds two new pgtable functions pte_clear_soft_dirty and pmd_clear_soft_dirty which is why there is a hit to arch/x86/include/asm/pgtable.h in this pull request. - A series of cleanup patches for the AP bus, this includes the removal of the support for two outdated crypto cards (PCICC and PCICA). - The irq handling / signaling on buffer full in the runtime instrumentation code is dropped. - Some micro optimizations: remove unnecessary memory barriers for a couple of functions: [smb_]rmb, [smb_]wmb, atomics, bitops, and for spin_unlock. Use the builtin bswap if available and make test_and_set_bit_lock more cache friendly. - Statistics and a tracepoint for the diagnose calls to the hypervisor. - The CPU measurement facility support to sample KVM guests is improved. - The vector instructions are now always enabled for user space processes if the hardware has the vector facility. This simplifies the FPU handling code. The fpu-internal.h header is split into fpu internals, api and types just like x86. - Cleanup and improvements for the common I/O layer. - Rework udelay to solve a problem with kprobe. udelay has busy loop semantics but still uses an idle processor state for the wait" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (66 commits) s390: remove runtime instrumentation interrupts s390/cio: de-duplicate subchannel validation s390/css: unneeded initialization in for_each_subchannel s390/Kconfig: use builtin bswap s390/dasd: fix disconnected device with valid path mask s390/dasd: fix invalid PAV assignment after suspend/resume s390/dasd: fix double free in dasd_eckd_read_conf s390/kernel: fix ptrace peek/poke for floating point registers s390/cio: move ccw_device_stlck functions s390/cio: move ccw_device_call_handler s390/topology: reduce per_cpu() invocations s390/nmi: reduce size of percpu variable s390/nmi: fix terminology s390/nmi: remove casts s390/nmi: remove pointless error strings s390: don't store registers on disabled wait anymore s390: get rid of __set_psw_mask() s390/fpu: split fpu-internal.h into fpu internals, api, and type headers s390/dasd: fix list_del corruption after lcu changes s390/spinlock: remove unneeded serializations at unlock ...
2015-11-03s390: remove runtime instrumentation interruptsMartin Schwidefsky3-63/+3
The external interrupts for runtime instrumentation buffer-full and runtime instrumentation halted are unused and have no current user. Remove the support and ignore the second parameter of the s390_runtime_instr system call from now on. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-03s390/kernel: fix ptrace peek/poke for floating point registersMartin Schwidefsky1-4/+4
git commit 155e839a814834a3b4b31e729f4716e59d3d2dd4 "s390/kernel: dynamically allocate FP register save area" introduced a regression in regard to ptrace. If the vector register extension is not present or unused the ptrace peek of a floating pointer register return incorrect data and the ptrace poke to a floating pointer register overwrites the task structure starting at task->thread.fpu.fprs. Cc: stable@kernel.org # v4.3 Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27s390/topology: reduce per_cpu() invocationsHeiko Carstens1-12/+16
Each per_cpu() invocation generates extra code. Since there are a lot of similiar calls in the topology code we can avoid a lot of them. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27s390/nmi: reduce size of percpu variableHeiko Carstens1-3/+3
Change the flag fields within struct mcck_struct to simple bit fields to reduce the size of the structure which is used as percpu variable. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27s390/nmi: fix terminologyHeiko Carstens1-9/+9
According to the architecture registers are validated and not revalidated. So change comments and functions names to match. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27s390/nmi: remove castsHeiko Carstens1-26/+26
Remove all the casts to and from the machine check interruption code. This patch changes struct mci to a union, which contains an anonymous structure with the already known bits and in addition an unsigned long field, which contains the raw machine check interruption code. This allows to simply assign and decoce the interruption code value without the need for all those casts we had all the time. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-27s390/nmi: remove pointless error stringsHeiko Carstens1-17/+12
s390_handle_damage() has character string parameter which was used as a pointer to verbose error message. The hope was (a lot of years ago) when analyzing dumps that register R2 would still contain the pointer and therefore it would be rather easy to tell what went wrong. However gcc optimizes the strings away since a long time. And even if it wouldn't it is necessary to have a close look at the machine check interruption code to tell what's wrong. So remove the pointless error strings. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-16s390/fpu: split fpu-internal.h into fpu internals, api, and type headersHendrik Brueckner3-3/+2
Split the API and FPU type definitions into separate header files similar to "x86/fpu: Rename fpu-internal.h to fpu/internal.h" (78f7f1e54b). The new header files and their meaning are: asm/fpu/types.h: FPU related data types, needed for 'struct thread_struct' and 'struct task_struct'. asm/fpu/api.h: FPU related 'public' functions for other subsystems and device drivers. asm/fpu/internal.h: FPU internal functions mainly used to convert FPU register contents in signal handling. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/etr,stp: fix possible deadlock on machine checkHeiko Carstens2-14/+33
The first level machine check handler for etr and stp machine checks may call queue_work() while in nmi context. This may deadlock e.g. if the machine check happened when the interrupted context did hold a lock, that also will be acquired by queue_work(). Therefore split etr and stp machine check handling into first and second level handling. The second level handling will then issue the queue_work() call in process context which avoids the potential deadlock. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/udelay: make udelay have busy loop semanticsHeiko Carstens2-1/+4
When using systemtap it was observed that our udelay implementation is rather suboptimal if being called from a kprobe handler installed by systemtap. The problem observed when a kprobe was installed on lock_acquired(). When the probe was hit the kprobe handler did call udelay, which set up an (internal) timer and reenabled interrupts (only the clock comparator interrupt) and waited for the interrupt. This is an optimization to avoid that the cpu is busy looping while waiting that enough time passes. The problem is that the interrupt handler still does call irq_enter()/irq_exit() which then again can lead to a deadlock, since some accounting functions may take locks as well. If one of these locks is the same, which caused lock_acquired() to be called, we have a nice deadlock. This patch reworks the udelay code for the interrupts disabled case to immediately leave the low level interrupt handler when the clock comparator interrupt happens. That way no C code is being called and the deadlock cannot happen anymore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/cpumf: rework program parameter setting to detect guest samplesChristian Borntraeger5-21/+27
The program parameter can be used to mark hardware samples with some token. Previously, it was used to mark guest samples only. Improve the program parameter doubleword by combining two parts, the leftmost LPP part and the rightmost PID part. Set the PID part for processes by using the task PID. To distinguish host and guest samples for the kernel (PID part is zero), the guest must always set the program paramater to a non-zero value. Use the leftmost bit in the LPP part of the program parameter to be able to detect guest kernel samples. [brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced __LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts. And updated the commit message accordingly. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/asm: make use of the OFFSET macro to define assember constantsMartin Schwidefsky1-140/+148
The use of OFFSET instead of DEFINE makes the definitions in asm-offsets.c more readable. While we are at it sort the defines for struct _lowcore according to the field order and remove some unneeded defines. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/entry: add assembler macro to conveniently tests under maskHendrik Brueckner1-41/+65
Various functions in entry.S perform test-under-mask instructions to test for particular bits in memory. Because test-under-mask uses a mask value of one byte, the mask value and the offset into the memory must be calculated manually. This easily introduces errors and is hard to review and read. Introduce the TSTMSK assembler macro to specify a mask constant and let the macro calculate the offset and the byte mask to generate a test-under-mask instruction. The benefit is that existing symbolic constants can now be used for tests. Also the macro checks for zero mask values and mask values that consist of multiple bytes. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/fpu: add static FPU save area for init_taskHendrik Brueckner2-4/+4
Previously, the init task did not have an allocated FPU save area and saving an FPU state was not possible. Now if the vector extension is always enabled, provide a static FPU save area to save FPU states of vector instructions that can be executed quite early. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/fpu: always enable the vector facility if it is availableHendrik Brueckner10-179/+68
If the kernel detects that the s390 hardware supports the vector facility, it is enabled by default at an early stage. To force it off, use the novx kernel parameter. Note that there is a small time window, where the vector facility is enabled before it is forced to be off. With enabling the vector facility by default, the FPU save and restore functions can be improved. They do not longer require to manage expensive control register updates to enable or disable the vector enablement control for particular processes. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/diag: add tracepoint for diagnose callsMartin Schwidefsky4-4/+53
To be able to analyse problems in regard to hypervisor overhead add a tracepoing for diagnose calls. It reports the number of the diagnose issued, e.g. sshd-1385 [002] .... 42.701431: diagnose: nr=0x9c <idle>-0 [001] ..s. 43.587528: diagnose: nr=0x9c Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/diag: add a statistic for diagnose callsMartin Schwidefsky6-5/+138
Introduce /sys/debug/kernel/diag_stat with a statistic how many diagnose calls have been done by each CPU in the system. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/crash_dump: use for_each_mem_rangeAlexander Kuleshov1-12/+4
The <linux/memblock.h> already provides for_each_mem_range