kernel/git/stable/linux.git/arch/arm/include, branch linux-3.18.y

ARM: fix put_user() for gcc-8

2018-07-28T05:43:19+00:00

Building kernels before linux-4.7 with gcc-8 results in many build failures when gcc triggers a check that was meant to catch broken compilers: /tmp/ccCGMQmS.s:648: Error: .err encountered According to the discussion in the gcc bugzilla, a local "register asm()" variable is still supposed to be the correct way to force an inline assembly to use a particular register, but marking it 'const' lets the compiler do optimizations that break that, i.e the compiler is free to treat the variable as either 'const' or 'register' in that case. Upstream commit 9f73bd8bb445 ("ARM: uaccess: remove put_user() code duplication") fixed this problem in linux-4.8 as part of a larger change, but seems a little too big to be backported to 4.4. Let's take the simplest fix and change only the one broken line in the same way as newer kernels. Suggested-by: Bernd Edlinger Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85745 Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86673 Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

ARM: 8764/1: kgdb: fix NUMREGBYTES so that gdb_regs[] is the correct size

2018-07-03T09:18:46+00:00

commit 76ed0b803a2ab793a1b27d1dfe0de7955282cd34 upstream. NUMREGBYTES (which is used as the size for gdb_regs[]) is incorrectly based on DBG_MAX_REG_NUM instead of GDB_MAX_REGS. DBG_MAX_REG_NUM is the number of total registers, while GDB_MAX_REGS is the number of 'unsigned longs' it takes to serialize those registers. Since FP registers require 3 'unsigned longs' each, DBG_MAX_REG_NUM is smaller than GDB_MAX_REGS. This causes GDB 8.0 give the following error on connect: "Truncated register 19 in remote 'g' packet" This also causes the register serialization/deserialization logic to overflow gdb_regs[], overwriting whatever follows. Fixes: 834b2964b7ab ("kgdb,arm: fix register dump") Cc: # 2.6.37+ Signed-off-by: David Rivshin Acked-by: Rabin Vincent Tested-by: Daniel Thompson Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman

ARM: 8772/1: kprobes: Prohibit kprobes on get_user functions

2018-05-25T08:54:57+00:00

commit 0d73c3f8e7f6ee2aab1bb350f60c180f5ae21a2c upstream. Since do_undefinstr() uses get_user to get the undefined instruction, it can be called before kprobes processes recursive check. This can cause an infinit recursive exception. Prohibit probing on get_user functions. Fixes: 24ba613c9d6c ("ARM kprobes: core code") Signed-off-by: Masami Hiramatsu Cc: stable@vger.kernel.org Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman

xen: avoid type warning in xchg_xen_ulong

2018-04-13T17:52:20+00:00

[ Upstream commit 9cc91f212111cdcbefa02dcdb7dd443f224bf52c ] The improved type-checking version of container_of() triggers a warning for xchg_xen_ulong, pointing out that 'xen_ulong_t' is unsigned, but atomic64_t contains a signed value: drivers/xen/events/events_2l.c: In function 'evtchn_2l_handle_events': drivers/xen/events/events_2l.c:187:1020: error: call to '__compiletime_assert_187' declared with attribute error: pointer type mismatch in container_of() This adds a cast to work around the warning. Cc: Ian Abbott Fixes: 85323a991d40 ("xen: arm: mandate EABI and use generic atomic operations.") Fixes: daa2ac80834d ("kernel.h: handle pointers to arrays better in container_of()") Signed-off-by: Arnd Bergmann Signed-off-by: Stefano Stabellini Reviewed-by: Stefano Stabellini Acked-by: Ian Abbott Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one

2017-12-16T09:32:31+00:00

commit 5553b142be11e794ebc0805950b2e8313f93d718 upstream. VTTBR_BADDR_MASK is used to sanity check the size and alignment of the VTTBR address. It seems to currently be off by one, thereby only allowing up to 39-bit addresses (instead of 40-bit) and also insufficiently checking the alignment. This patch fixes it. This patch is the 32bit pendent of Kristina's arm64 fix, and she deserves the actual kudos for pinpointing that one. Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation") Reported-by: Kristina Martsenko Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman

arm: KVM: Survive unknown traps from guests

2017-12-16T09:32:29+00:00

[ Upstream commit f050fe7a9164945dd1c28be05bf00e8cfb082ccf ] Currently we BUG() if we see a HSR.EC value we don't recognise. As configurable disables/enables are added to the architecture (controlled by RES1/RES0 bits respectively), with associated synchronous exceptions, it may be possible for a guest to trigger exceptions with classes that we don't recognise. While we can't service these exceptions in a manner useful to the guest, we can avoid bringing down the host. Per ARM DDI 0406C.c, all currently unallocated HSR EC encodings are reserved, and per ARM DDI 0487A.k_iss10775, page G6-4395, EC values within the range 0x00 - 0x2c are reserved for future use with synchronous exceptions, and EC values within the range 0x2d - 0x3f may be used for either synchronous or asynchronous exceptions. The patch makes KVM handle any unknown EC by injecting an UNDEFINED exception into the guest, with a corresponding (ratelimited) warning in the host dmesg. We could later improve on this with with a new (opt-in) exit to the host userspace. Cc: Dave Martin Cc: Suzuki K Poulose Reviewed-by: Christoffer Dall Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ARM: 8715/1: add a private asm/unaligned.h

2017-11-08T09:03:48+00:00

commit 1cce91dfc8f7990ca3aea896bfb148f240b12860 upstream. The asm-generic/unaligned.h header provides two different implementations for accessing unaligned variables: the access_ok.h version used when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set pretends that all pointers are in fact aligned, while the le_struct.h version convinces gcc that the alignment of a pointer is '1', to make it issue the correct load/store instructions depending on the architecture flags. On ARMv5 and older, we always use the second version, to let the compiler use byte accesses. On ARMv6 and newer, we currently use the access_ok.h version, so the compiler can use any instruction including stm/ldm and ldrd/strd that will cause an alignment trap. This trap can significantly impact performance when we have to do a lot of fixups and, worse, has led to crashes in the LZ4 decompressor code that does not have a trap handler. This adds an ARM specific version of asm/unaligned.h that uses the le_struct.h/be_struct.h implementation unconditionally. This should lead to essentially the same code on ARMv6+ as before, with the exception of using regular load/store instructions instead of the trapping instructions multi-register variants. The crash in the LZ4 decompressor code was probably introduced by the patch replacing the LZ4 implementation, commit 4e1a33b105dd ("lib: update LZ4 compressor module"), so linux-4.11 and higher would be affected most. However, we probably want to have this backported to all older stable kernels as well, to help with the performance issues. There are two follow-ups that I think we should also work on, but not backport to stable kernels, first to change the asm-generic version of the header to remove the ARM special case, and second to review all other uses of CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to see if they might be affected by the same problem on ARM. Signed-off-by: Arnd Bergmann Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman

ARM: 8632/1: ftrace: fix syscall name matching

2017-08-11T16:30:16+00:00

[ Upstream commit 270c8cf1cacc69cb8d99dea812f06067a45e4609 ] ARM has a few system calls (most notably mmap) for which the names of the functions which are referenced in the syscall table do not match the names of the syscall tracepoints. As a consequence of this, these tracepoints are not made available. Implement arch_syscall_match_sym_name to fix this and allow tracing even these system calls. Signed-off-by: Rabin Vincent Signed-off-by: Russell King Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Revert "ARM: 8457/1: psci-smp is built only for SMP"

2017-04-22T05:14:58+00:00

This reverts commit dbcfee724255ae171af51aaa56d8c5b78342adc9 which is commit be95485a0b8288a93402705730d3ea32f9f812b9 upstream. Upstream commit be95485 (ARM: 8457/1: psci-smp is built only for SMP) was intended to fix the build error for configs with CONFIG_SMP=n and CONFIG_ARM_PSCI=y, but it end up introducing a build error when cherry-picked on 3.18.y. This patch resulted in redefinition of psci_init() and broke the build for every build config in 3.18.y with CONFIG_SMP=n and CONFIG_ARM_PSCI=y. Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman

ARM: 8584/1: floppy: avoid gcc-6 warning

2017-04-18T05:55:45+00:00

commit dd665be0e243873343a28e18f9f345927b658daf upstream. gcc-6.0 warns about comparisons between two identical expressions, which is what we get in the floppy driver when writing to the FD_DOR register: drivers/block/floppy.c: In function 'set_dor': drivers/block/floppy.c:810:44: error: self-comparison always evaluates to true [-Werror=tautological-compare] fd_outb(newdor, FD_DOR); It would be nice to use a static inline function instead of the macro, to avoid the warning, but we cannot do that because the FD_DOR definition is incomplete at this point. Adding a cast to (u32) is a harmless way to shut up the warning, just not very nice. Signed-off-by: Arnd Bergmann Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman