4.4-stable review patch. If anyone has any objections, please let me know.
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From: Maciej W. Rozycki macro@mips.com
commit c7e814628df65f424fe197dde73bfc67e4a244d7 upstream.
Use 64-bit accesses for 64-bit floating-point general registers with PTRACE_PEEKUSR, removing the truncation of their upper halves in the FR=1 mode, caused by commit bbd426f542cb ("MIPS: Simplify FP context access"), which inadvertently switched them to using 32-bit accesses.
The PTRACE_POKEUSR side is fine as it's never been broken and continues using 64-bit accesses.
Fixes: bbd426f542cb ("MIPS: Simplify FP context access") Signed-off-by: Maciej W. Rozycki macro@mips.com Cc: Ralf Baechle ralf@linux-mips.org Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.15+ Patchwork: https://patchwork.linux-mips.org/patch/19334/ Signed-off-by: James Hogan jhogan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/mips/kernel/ptrace.c | 2 +- arch/mips/kernel/ptrace32.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
--- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -841,7 +841,7 @@ long arch_ptrace(struct task_struct *chi break; } #endif - tmp = get_fpr32(&fregs[addr - FPR_BASE], 0); + tmp = get_fpr64(&fregs[addr - FPR_BASE], 0); break; case PC: tmp = regs->cp0_epc; --- a/arch/mips/kernel/ptrace32.c +++ b/arch/mips/kernel/ptrace32.c @@ -107,7 +107,7 @@ long compat_arch_ptrace(struct task_stru addr & 1); break; } - tmp = get_fpr32(&fregs[addr - FPR_BASE], 0); + tmp = get_fpr64(&fregs[addr - FPR_BASE], 0); break; case PC: tmp = regs->cp0_epc;