From: Maciej W. Rozycki <macro@xxxxxxxx> commit f5958b4cf4fc38ed4583ab83fb7c4cd1ab05f47b upstream. Use the `unsigned long' rather than `__u32' type for DSP accumulator registers, like with the regular MIPS multiply/divide accumulator and general-purpose registers, as all are 64-bit in 64-bit implementations and using a 32-bit data type leads to contents truncation on context saving. Update `arch_ptrace' and `compat_arch_ptrace' accordingly, removing casts that are similarly not used with multiply/divide accumulator or general-purpose register accesses. Signed-off-by: Maciej W. Rozycki <macro@xxxxxxxx> Signed-off-by: Paul Burton <paul.burton@xxxxxxxx> Fixes: e50c0a8fa60d ("Support the MIPS32 / MIPS64 DSP ASE.") Patchwork: https://patchwork.linux-mips.org/patch/19329/ Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: James Hogan <jhogan@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: linux-fsdevel@xxxxxxxxxxxxxxx Cc: linux-mips@xxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx # 2.6.15+ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/mips/include/asm/processor.h | 2 +- arch/mips/kernel/ptrace.c | 2 +- arch/mips/kernel/ptrace32.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -143,7 +143,7 @@ struct mips_fpu_struct { #define NUM_DSP_REGS 6 -typedef __u32 dspreg_t; +typedef unsigned long dspreg_t; struct mips_dsp_state { dspreg_t dspr[NUM_DSP_REGS]; --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -751,7 +751,7 @@ long arch_ptrace(struct task_struct *chi goto out; } dregs = __get_dsp_regs(child); - tmp = (unsigned long) (dregs[addr - DSP_BASE]); + tmp = dregs[addr - DSP_BASE]; break; } case DSP_CONTROL: --- a/arch/mips/kernel/ptrace32.c +++ b/arch/mips/kernel/ptrace32.c @@ -140,7 +140,7 @@ long compat_arch_ptrace(struct task_stru goto out; } dregs = __get_dsp_regs(child); - tmp = (unsigned long) (dregs[addr - DSP_BASE]); + tmp = dregs[addr - DSP_BASE]; break; } case DSP_CONTROL: Patches currently in stable-queue which might be from macro@xxxxxxxx are queue-3.18/mips-correct-the-64-bit-dsp-accumulator-register-size.patch