linux/arch/mips/include, branch v4.5

mips: Differentiate between 32 and 64 bit ELF header

2016-02-11T10:38:22Z

Depending on the configuration either the 32 or 64 bit version of elf_check_arch() is defined. parse_crash_elf{32|64}_headers() does some basic verification of the ELF header via vmcore_elf{32|64}_check_arch() which happen to map to elf_check_arch(). Since the implementation 32 and 64 bit version of elf_check_arch() differ, we use the wrong type: In file included from include/linux/elf.h:4:0, from fs/proc/vmcore.c:13: fs/proc/vmcore.c: In function 'parse_crash_elf64_headers': >> arch/mips/include/asm/elf.h:228:23: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types] struct elfhdr *__h = (hdr); \ ^ include/linux/crash_dump.h:41:37: note: in expansion of macro 'elf_check_arch' #define vmcore_elf64_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x)) ^ fs/proc/vmcore.c:1015:4: note: in expansion of macro 'vmcore_elf64_check_arch' !vmcore_elf64_check_arch(&ehdr) || ^ Therefore, we rather define vmcore_elf{32|64}_check_arch() as a basic machine check and use it also in binfm_elf?32.c as well. Signed-off-by: Daniel Wagner Suggested-by: Maciej W. Rozycki Reviewed-by: Maciej W. Rozycki Reported-by: Fengguang Wu Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12529/ Signed-off-by: Ralf Baechle

MIPS: Octeon: Update OCTEON_FEATURE_PCIE for Octeon III

2016-02-10T14:08:53Z

Currently the driver tries to probe the pci driver and oops. Add CN7XXX to case so that driver probes the pcie driver. Signed-off-by: Zubair Lutfullah Kakakhel Cc: david.daney@cavium.com Cc: matt.redfearn@imgtec.com Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12530/ Signed-off-by: Ralf Baechle

MIPS: Wire up copy_file_range syscall.

2016-02-05T16:15:42Z

Signed-off-by: Ralf Baechle

MIPS: Fix 64k page support for 32 bit kernels.

2016-02-04T00:24:40Z

TASK_SIZE was defined as 0x7fff8000UL which for 64k pages is not a multiple of the page size. Somewhere further down the math fails such that executing an ELF binary fails. Signed-off-by: Ralf Baechle Tested-by: Joshua Henderson

MIPS: Fix FPU disable with preemption

2016-02-01T22:36:38Z

The FPU should not be left enabled after a task context switch. This isn't usually a problem as the FPU enable bit is updated before returning to userland, however it can potentially mask kernel bugs, and in fact KVM assumes it won't happen and won't clear the FPU enable bit before returning to the guest, which allows the guest to use stale FPU context. Interrupts and exceptions save and restore most bits of the CP0 Status register which contains the FPU enable bit (CU1). When the kernel needs to enable or disable the FPU (for example due to attempted FPU use by userland, or the scheduler being invoked) both the actual Status register and the saved value in the userland context are updated. However this doesn't work correctly with full kernel preemption enabled, since the FPU enable bit can be cleared from within an interrupt when the scheduler is invoked, and only the userland context is updated, not the interrupt context. For example: 1) Enter kernel with FPU already enabled, TIF_USEDFPU=1, Status.CU1=1 saved. 2) Take a timer interrupt while in kernel mode, Status.CU1=1 saved. 3) Timer interrupt invokes scheduler to preempt the task, which clears TIF_USEDFPU, disables the FPU in Status register (Status.CU1=0), and the value stored in user context from step (1), but not the interrupt context from step (2). 4) When the process is scheduled back in again Status.CU1=0. 5) The interrupt context from step (2) is restored, which sets Status.CU1=1. So from user context point of view, preemption has re-enabled FPU! 6) If the scheduler is invoked again (via preemption or voluntarily) before returning to userland, TIF_USEDFPU=0 so the FPU is not disabled before the task context switch. 7) The next task resumes from the context switch with FPU enabled! The restoring of the Status register on return from interrupt/exception is already selective about which bits to restore, leaving the interrupt mask bits alone so enabling/disabling of CPU interrupt lines can persist. Extend this to also leave both the CU1 bit (FPU enable) and the FR bit (which specifies the FPU mode and gets changed with CU1). This prevents a stale Status value being restored in step (5) above and persisting through subsequent context switches. Also switch to the use of definitions from asm/mipsregs.h while we're at it. Since this change also affects the restoration of Status register on the path back to userland, it increases the sensitivity of the kernel to the problem of the FPU being left enabled, allowing it to propagate to userland, therefore a warning is also added to lose_fpu_inatomic() to point out any future reoccurances before they do any damage. Signed-off-by: James Hogan Reviewed-by: Paul Burton Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12303/ Signed-off-by: Ralf Baechle

MIPS: Fix buffer overflow in syscall_get_arguments()

2016-02-01T22:27:08Z

Since commit 4c21b8fd8f14 ("MIPS: seccomp: Handle indirect system calls (o32)"), syscall_get_arguments() attempts to handle o32 indirect syscall arguments by incrementing both the start argument number and the number of arguments to fetch. However only the start argument number needs to be incremented. The number of arguments does not change, they're just shifted up by one, and in fact the output array is provided by the caller and is likely only n entries long, so reading more arguments overflows the output buffer. In the case of seccomp, this results in it fetching 7 arguments starting at the 2nd one, which overflows the unsigned long args[6] in populate_seccomp_data(). This clobbers the $s0 register from syscall_trace_enter() which __seccomp_phase1_filter() saved onto the stack, into which syscall_trace_enter() had placed its syscall number argument. This caused Chromium to crash. Credit goes to Milko for tracking it down as far as $s0 being clobbered. Fixes: 4c21b8fd8f14 ("MIPS: seccomp: Handle indirect system calls (o32)") Reported-by: Milko Leporis Signed-off-by: James Hogan Cc: linux-mips@linux-mips.org Cc: # 3.15- Patchwork: https://patchwork.linux-mips.org/patch/12213/ Signed-off-by: Ralf Baechle

Revert "MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function"

2016-01-27T19:51:50Z

This reverts commit 5bdb102b3f9785cb88467bc7c75fa0f5cacc8dc5. Brian Norris is reporting: Ralf, Please revert this and send it to Linus (or else, I can send it myself). This is causing build failures, because I didn't take the rest of Simon's series yet. drivers/mtd/bcm63xxpart.c: In function 'bcm63xx_parse_cfe_partitions': drivers/mtd/bcm63xxpart.c:93:2: error: implicit declaration of function 'bcm63xx_nvram_get_psi_size' [-Werror=implicit-function-declaration] Signed-off-by: Ralf Baechle References: https://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=20160126191607.GA111152%40google.com

Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

2016-01-24T20:50:56Z

Pull MIPS updates from Ralf Baechle: "This is the main pull request for MIPS for 4.5 plus some 4.4 fixes. The executive summary: - ATH79 platform improvments, use DT bindings for the ATH79 USB PHY. - Avoid useless rebuilds for zboot. - jz4780: Add NEMC, BCH and NAND device tree nodes - Initial support for the MicroChip's DT platform. As all the device drivers are missing this is still of limited use. - Some Loongson3 cleanups. - The unavoidable whitespace polishing. - Reduce clock skew when synchronizing the CPU cycle counters on CPU startup. - Add MIPS R6 fixes. - Lots of cleanups across arch/mips as fallout from KVM. - Lots of minor fixes and changes for IEEE 754-2008 support to the FPU emulator / fp-assist software. - Minor Ralink, BCM47xx and bcm963xx platform support improvments. - Support SMP on BCM63168" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (84 commits) MIPS: zboot: Add support for serial debug using the PROM MIPS: zboot: Avoid useless rebuilds MIPS: BMIPS: Enable ARCH_WANT_OPTIONAL_GPIOLIB MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function MIPS: bcm963xx: Update bcm_tag field image_sequence MIPS: bcm963xx: Move extended flash address to bcm_tag header file MIPS: bcm963xx: Move Broadcom BCM963xx image tag data structure MIPS: bcm63xx: nvram: Use nvram structure definition from header file MIPS: bcm963xx: Add Broadcom BCM963xx board nvram data structure MAINTAINERS: Add KVM for MIPS entry MIPS: KVM: Add missing newline to kvm_err() MIPS: Move KVM specific opcodes into asm/inst.h MIPS: KVM: Use cacheops.h definitions MIPS: Break down cacheops.h definitions MIPS: Use EXCCODE_ constants with set_except_vector() MIPS: Update trap codes MIPS: Move Cause.ExcCode trap codes to mipsregs.h MIPS: KVM: Make kvm_mips_{init,exit}() static MIPS: KVM: Refactor added offsetof()s MIPS: KVM: Convert EXPORT_SYMBOL to _GPL ...

Merge branch '4.4-fixes' into mips-for-linux-next

2016-01-24T03:14:40Z

MIPS: bcm63xx: nvram: Remove unused bcm63xx_nvram_get_psi_size() function

2016-01-24T02:49:27Z

Remove bcm63xx_nvram_get_psi_size() as it now has no users. Signed-off-by: Simon Arlott Cc: David Woodhouse Cc: Brian Norris Cc: Kevin Cernekee Cc: Florian Fainelli Cc: Jonas Gorski Cc: Linux Kernel Mailing List Cc: MIPS Mailing List Cc: MTD Maling List Patchwork: https://patchwork.linux-mips.org/patch/11836/ Signed-off-by: Ralf Baechle