Searched hist:da0bac33413b2888d3623dad3ad19ce76b688f07 (Results 1 – 1 of 1) sorted by relevance
| /linux/arch/mips/math-emu/ |
| H A D | cp1emu.c | diff 51d943f07d3015998d448f9d8353f618e3fe5873 Wed Aug 15 19:42:19 CEST 2012 Ralf Baechle <ralf@linux-mips.org> MIPS: Fix for warning from FPU emulation code
The default implementation of 'cpu_has_fpu' macro calls
smp_processor_id() which causes this warning to be printed when
preemption is enabled:
[ 4.664000] Algorithmics/MIPS FPU Emulator v1.5
[ 4.676000] BUG: using smp_processor_id() in preemptible [00000000] code: ini
[ 4.700000] caller is fpu_emulator_cop1Handler+0x434/0x27b8
This problem got introduced in November 2009 by
af1d2af877ef6c36990671bc86a5b9c5bb50b1da (lmo) [MIPS: Fix emulation of
64-bit FPU on 64-bit CPUs.] rsp. da0bac33413b2888d3623dad3ad19ce76b688f07
(kernel.org) [MIPS: Fix emulation of 64-bit FPU on FPU-less 64-bit CPUs.]
in 2.6.32.
Fixed by rewriting cop1_64bit() to return a constant whenever possible
but most importantly avoid the use pf cpu_has_fpu entirely.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Jayachandran C <jchandra@broadcom.com>
Initial-patch-by: Jayachandran C <jchandra@broadcom.com>
Patchwork: https://patchwork.linux-mips.org/patch/4225/
diff da0bac33413b2888d3623dad3ad19ce76b688f07 Mon Nov 02 20:33:46 CET 2009 David Daney <ddaney@caviumnetworks.com> MIPS: Fix emulation of 64-bit FPU on FPU-less 64-bit CPUs.
Running a 64-bit kernel on a 64-bit CPU without an FPU would cause the
emulator to run in 32-bit mode. The c0_Status.FR bit is wired to zero
on systems without an FPU, so using that bit to decide how the emulator
behaves doesn't allow for proper emulation on 64-bit FPU-less
processors.
Instead, we need to select the emulator mode based on the user-space
ABI. Since the thread flag TIF_32BIT_REGS is used to set c0_Status.FR,
we can just use it to decide if the emulator should be in 32-bit or
64-bit mode.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|