user/sven/linux.git/arch/mips, branch v4.4.118

MIPS: AR7: ensure the port type's FCR value is used

2018-01-23T18:50:18Z

commit 0a5191efe06b5103909206e4fbcff81d30283f8e upstream. Since commit aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt trigger I/F of FIFO buffers"), the port's default FCR value isn't used in serial8250_do_set_termios anymore, but copied over once in serial8250_config_port and then modified as needed. Unfortunately, serial8250_config_port will never be called if the port is shared between kernel and userspace, and the port's flag doesn't have UPF_BOOT_AUTOCONF, which would trigger a serial8250_config_port as well. This causes garbled output from userspace: [ 5.220000] random: procd urandom read with 49 bits of entropy available ers [kee Fix this by forcing it to be configured on boot, resulting in the expected output: [ 5.250000] random: procd urandom read with 50 bits of entropy available Press the [f] key and hit [enter] to enter failsafe mode Press the [1], [2], [3] or [4] key and hit [enter] to select the debug level Fixes: aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt trigger I/F of FIFO buffers") Signed-off-by: Jonas Gorski Cc: Greg Kroah-Hartman Cc: Yoshihiro YUNOMAE Cc: Florian Fainelli Cc: Nicolas Schichan Cc: linux-mips@linux-mips.org Cc: linux-serial@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17544/ Signed-off-by: Ralf Baechle Cc: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses

2018-01-17T08:35:25Z

commit c8c5a3a24d395b14447a9a89d61586a913840a3b upstream. Complement commit c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use correct core dump register layout") and also reject outsized PTRACE_SETREGSET requests to the NT_PRFPREG regset, like with the NT_PRSTATUS regset. Signed-off-by: Maciej W. Rozycki Fixes: c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use correct core dump register layout") Cc: James Hogan Cc: Paul Burton Cc: Alex Smith Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17930/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET

2018-01-17T08:35:25Z

commit 006501e039eec411842bb3150c41358867d320c2 upstream. Complement commit d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write") and like with the PTRACE_GETREGSET ptrace(2) request also apply a BUILD_BUG_ON check for the size of the `elf_fpreg_t' type in the PTRACE_SETREGSET request handler. Signed-off-by: Maciej W. Rozycki Fixes: d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write") Cc: James Hogan Cc: Paul Burton Cc: Alex Smith Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17929/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Fix an FCSR access API regression with NT_PRFPREG and MSA

2018-01-17T08:35:25Z

commit be07a6a1188372b6d19a3307ec33211fc9c9439d upstream. Fix a commit 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset") public API regression, then activated by commit 1db1af84d6df ("MIPS: Basic MSA context switching support"), that caused the FCSR register not to be read or written for CONFIG_CPU_HAS_MSA kernel configurations (regardless of actual presence or absence of the MSA feature in a given processor) with ptrace(2) PTRACE_GETREGSET and PTRACE_SETREGSET requests nor recorded in core dumps. This is because with !CONFIG_CPU_HAS_MSA configurations the whole of `elf_fpregset_t' array is bulk-copied as it is, which includes the FCSR in one half of the last, 33rd slot, whereas with CONFIG_CPU_HAS_MSA configurations array elements are copied individually, and then only the leading 32 FGR slots while the remaining slot is ignored. Correct the code then such that only FGR slots are copied in the respective !MSA and MSA helpers an then the FCSR slot is handled separately in common code. Use `ptrace_setfcr31' to update the FCSR too, so that the read-only mask is respected. Retrieving a correct value of FCSR is important in debugging not only for the human to be able to get the right interpretation of the situation, but for correct operation of GDB as well. This is because the condition code bits in FSCR are used by GDB to determine the location to place a breakpoint at when single-stepping through an FPU branch instruction. If such a breakpoint is placed incorrectly (i.e. with the condition reversed), then it will be missed, likely causing the debuggee to run away from the control of GDB and consequently breaking the process of investigation. Fortunately GDB continues using the older PTRACE_GETFPREGS ptrace(2) request which is unaffected, so the regression only really hits with post-mortem debug sessions using a core dump file, in which case execution, and consequently single-stepping through branches is not possible. Of course core files created by buggy kernels out there will have the value of FCSR recorded clobbered, but such core files cannot be corrected and the person using them simply will have to be aware that the value of FCSR retrieved is not reliable. Which also means we can likely get away without defining a replacement API which would ensure a correct value of FSCR to be retrieved, or none at all. This is based on previous work by Alex Smith, extensively rewritten. Signed-off-by: Alex Smith Signed-off-by: James Hogan Signed-off-by: Maciej W. Rozycki Fixes: 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset") Cc: Paul Burton Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17928/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Consistently handle buffer counter with PTRACE_SETREGSET

2018-01-17T08:35:25Z

commit 80b3ffce0196ea50068885d085ff981e4b8396f4 upstream. Update commit d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write") bug and consistently consume all data supplied to `fpr_set_msa' with the ptrace(2) PTRACE_SETREGSET request, such that a zero data buffer counter is returned where insufficient data has been given to fill a whole number of FP general registers. In reality this is not going to happen, as the caller is supposed to only supply data covering a whole number of registers and it is verified in `ptrace_regset' and again asserted in `fpr_set', however structuring code such that the presence of trailing partial FP general register data causes `fpr_set_msa' to return with a non-zero data buffer counter makes it appear that this trailing data will be used if there are subsequent writes made to FP registers, which is going to be the case with the FCSR once the missing write to that register has been fixed. Fixes: d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write") Signed-off-by: Maciej W. Rozycki Cc: James Hogan Cc: Paul Burton Cc: Alex Smith Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17927/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Guard against any partial write attempt with PTRACE_SETREGSET

2018-01-17T08:35:24Z

commit dc24d0edf33c3e15099688b6bbdf7bdc24bf6e91 upstream. Complement commit d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write") and ensure that no partial register write attempt is made with PTRACE_SETREGSET, as we do not preinitialize any temporaries used to hold incoming register data and consequently random data could be written. It is the responsibility of the caller, such as `ptrace_regset', to arrange for writes to span whole registers only, so here we only assert that it has indeed happened. Signed-off-by: Maciej W. Rozycki Fixes: 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset") Cc: James Hogan Cc: Paul Burton Cc: Alex Smith Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17926/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Factor out NT_PRFPREG regset access helpers

2018-01-17T08:35:24Z

commit a03fe72572c12e98f4173f8a535f32468e48b6ec upstream. In preparation to fix a commit 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset") FCSR access regression factor out NT_PRFPREG regset access helpers for the non-MSA and the MSA variants respectively, to avoid having to deal with excessive indentation in the actual fix. No functional change, however use `target->thread.fpu.fpr[0]' rather than `target->thread.fpu.fpr[i]' for FGR holding type size determination as there's no `i' variable to refer to anymore, and for the factored out `i' variable declaration use `unsigned int' rather than `unsigned' as its type, following the common style. Signed-off-by: Maciej W. Rozycki Fixes: 72b22bbad1e7 ("MIPS: Don't assume 64-bit FP registers for FP regset") Cc: James Hogan Cc: Paul Burton Cc: Alex Smith Cc: Dave Martin Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17925/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: Validate PR_SET_FP_MODE prctl(2) requests against the ABI of the task

2018-01-17T08:35:24Z

commit b67336eee3fcb8ecedc6c13e2bf88aacfa3151e2 upstream. Fix an API loophole introduced with commit 9791554b45a2 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS"), where the caller of prctl(2) is incorrectly allowed to make a change to CP0.Status.FR or CP0.Config5.FRE register bits even if CONFIG_MIPS_O32_FP64_SUPPORT has not been enabled, despite that an executable requesting the mode requested via ELF file annotation would not be allowed to run in the first place, or for n64 and n64 ABI tasks which do not have non-default modes defined at all. Add suitable checks to `mips_set_process_fp_mode' and bail out if an invalid mode change has been requested for the ABI in effect, even if the FPU hardware or emulation would otherwise allow it. Always succeed however without taking any further action if the mode requested is the same as one already in effect, regardless of whether any mode change, should it be requested, would actually be allowed for the task concerned. Signed-off-by: Maciej W. Rozycki Fixes: 9791554b45a2 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS") Reviewed-by: Paul Burton Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17800/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman

MIPS: math-emu: Fix final emulation phase for certain instructions

2017-12-25T13:22:15Z

commit 409fcace9963c1e8d2cb0f7ac62e8b34d47ef979 upstream. Fix final phase of . emulation. Provide proper generation of SIGFPE signal and updating debugfs FP exception stats in cases of any exception flags set in preceding phases of emulation. CLASS. instruction may generate "Unimplemented Operation" FP exception. . instructions may generate "Inexact", "Unimplemented Operation", "Invalid Operation", "Overflow", and "Underflow" FP exceptions. . instructions can generate "Unimplemented Operation" and "Invalid Operation" FP exceptions. The proper final processing of the cases when any FP exception flag is set is achieved by replacing "break" statement with "goto copcsr" statement. With such solution, this patch brings the final phase of emulation of the above instructions consistent with the one corresponding to the previously implemented emulation of other related FPU instructions (ADD, SUB, etc.). Fixes: 38db37ba069f ("MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction") Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction") Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction") Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction") Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction") Signed-off-by: Aleksandar Markovic Cc: Ralf Baechle Cc: Douglas Leung Cc: Goran Ferenc Cc: "Maciej W. Rozycki" Cc: Miodrag Dinic Cc: Paul Burton Cc: Petar Jovanovic Cc: Raghu Gandham Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17581/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman

MIPS: BCM47XX: Fix LED inversion for WRT54GSv1

2017-11-30T08:37:20Z

commit 56a46acf62af5ba44fca2f3f1c7c25a2d5385b19 upstream. The WLAN LED on the Linksys WRT54GSv1 is active low, but the software treats it as active high. Fix the inverted logic. Fixes: 7bb26b169116 ("MIPS: BCM47xx: Fix LEDs on WRT54GS V1.0") Signed-off-by: Mirko Parthey Looks-ok-by: Rafał Miłecki Cc: Hauke Mehrtens Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/16071/ Signed-off-by: James Hogan Signed-off-by: Greg Kroah-Hartman