linux.git/arch/mips, branch v4.4.215

MIPS: Loongson: Fix potential NULL dereference in loongson3_platform_init()

2020-02-28T14:38:54+00:00

[ Upstream commit 72d052e28d1d2363f9107be63ef3a3afdea6143c ]

If kzalloc fails, it should return -ENOMEM, otherwise may trigger a NULL
pointer dereference.

Fixes: 3adeb2566b9b ("MIPS: Loongson: Improve LEFI firmware interface")
Signed-off-by: Tiezhu Yang 
Signed-off-by: Paul Burton 
Cc: Ralf Baechle 
Cc: Huacai Chen 
Cc: Jiaxun Yang 
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sasha Levin

mips: avoid explicit UB in assignment of mips_io_port_base

2020-01-29T09:21:47+00:00

[ Upstream commit 12051b318bc3ce5b42d6d786191008284b067d83 ]

The code in question is modifying a variable declared const through
pointer manipulation.  Such code is explicitly undefined behavior, and
is the lone issue preventing malta_defconfig from booting when built
with Clang:

If an attempt is made to modify an object defined with a const-qualified
type through use of an lvalue with non-const-qualified type, the
behavior is undefined.

LLVM is removing such assignments. A simple fix is to not declare
variables const that you plan on modifying.  Limiting the scope would be
a better method of preventing unwanted writes to such a variable.

Further, the code in question mentions "compiler bugs" without any links
to bug reports, so it is difficult to know if the issue is resolved in
GCC. The patch was authored in 2006, which would have been GCC 4.0.3 or
4.1.1. The minimal supported version of GCC in the Linux kernel is
currently 4.6.

For what its worth, there was UB before the commit in question, it just
added a barrier and got lucky IRT codegen. I don't think there's any
actual compiler bugs related, just runtime bugs due to UB.

Link: https://github.com/ClangBuiltLinux/linux/issues/610
Fixes: 966f4406d903 ("[MIPS] Work around bad code generation for .")
Reported-by: Nathan Chancellor 
Debugged-by: Nathan Chancellor 
Suggested-by: Eli Friedman 
Signed-off-by: Nick Desaulniers 
Reviewed-by: Nathan Chancellor 
Tested-by: Nathan Chancellor 
Signed-off-by: Paul Burton 
Cc: ralf@linux-mips.org
Cc: jhogan@kernel.org
Cc: Maciej W. Rozycki 
Cc: Hassan Naveed 
Cc: Stephen Kitt 
Cc: Serge Semin 
Cc: Mike Rapoport 
Cc: Andrew Morton 
Cc: Michal Hocko 
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Signed-off-by: Sasha Levin

MIPS: Avoid VDSO ABI breakage due to global register variable

2020-01-12T10:22:41+00:00

commit bbcc5672b0063b0e9d65dc8787a4f09c3b5bb5cc upstream.

Declaring __current_thread_info as a global register variable has the
effect of preventing GCC from saving & restoring its value in cases
where the ABI would typically do so.

To quote GCC documentation:

> If the register is a call-saved register, call ABI is affected: the
> register will not be restored in function epilogue sequences after the
> variable has been assigned. Therefore, functions cannot safely return
> to callers that assume standard ABI.

When our position independent VDSO is built for the n32 or n64 ABIs all
functions it exposes should be preserving the value of $gp/$28 for their
caller, but in the presence of the __current_thread_info global register
variable GCC stops doing so & simply clobbers $gp/$28 when calculating
the address of the GOT.

In cases where the VDSO returns success this problem will typically be
masked by the caller in libc returning & restoring $gp/$28 itself, but
that is by no means guaranteed. In cases where the VDSO returns an error
libc will typically contain a fallback path which will now fail
(typically with a bad memory access) if it attempts anything which
relies upon the value of $gp/$28 - eg. accessing anything via the GOT.

One fix for this would be to move the declaration of
__current_thread_info inside the current_thread_info() function,
demoting it from global register variable to local register variable &
avoiding inadvertently creating a non-standard calling ABI for the VDSO.
Unfortunately this causes issues for clang, which doesn't support local
register variables as pointed out by commit fe92da0f355e ("MIPS: Changed
current_thread_info() to an equivalent supported by both clang and GCC")
which introduced the global register variable before we had a VDSO to
worry about.

Instead, fix this by continuing to use the global register variable for
the kernel proper but declare __current_thread_info as a simple extern
variable when building the VDSO. It should never be referenced, and will
cause a link error if it is. This resolves the calling convention issue
for the VDSO without having any impact upon the build of the kernel
itself for either clang or gcc.

Signed-off-by: Paul Burton 
Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
Reported-by: Jason A. Donenfeld 
Reviewed-by: Jason A. Donenfeld 
Tested-by: Jason A. Donenfeld 
Cc: Arnd Bergmann 
Cc: Christian Brauner 
Cc: Vincenzo Frascino 
Cc:  # v4.4+
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

MIPS: OCTEON: cvmx_pko_mem_debug8: use oldest forward compatible definition

2019-12-21T09:34:45+00:00

[ Upstream commit 1c6121c39677175bd372076020948e184bad4b6b ]

cn58xx is compatible with cn50xx, so use the latter.

Signed-off-by: Aaro Koskinen 
[paul.burton@mips.com: s/cn52xx/cn50xx/ in commit message.]
Signed-off-by: Paul Burton 
Cc: Ralf Baechle 
Cc: James Hogan 
Cc: linux-mips@vger.kernel.org
Signed-off-by: Sasha Levin

MIPS: OCTEON: octeon-platform: fix typing

2019-12-21T09:34:32+00:00

[ Upstream commit 2cf1c8933dd93088cfb5f8f58b3bb9bbdf1781b9 ]

Use correct type for fdt_property nameoff field.

Signed-off-by: Aaro Koskinen 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/21204/
Cc: Ralf Baechle 
Cc: James Hogan 
Cc: linux-mips@linux-mips.org
Signed-off-by: Sasha Levin

MIPS: SiByte: Enable ZONE_DMA32 for LittleSur

2019-12-21T09:34:29+00:00

[ Upstream commit 756d6d836dbfb04a5a486bc2ec89397aa4533737 ]

The LittleSur board is marked for high memory support and therefore
clearly must provide a way to have enough memory installed for some to
be present outside the low 4GiB physical address range.  With the memory
map of the BCM1250 SOC it has been built around it means over 1GiB of
actual DRAM, as only the first 1GiB is mapped in the low 4GiB physical
address range[1].

Complement commit cce335ae47e2 ("[MIPS] 64-bit Sibyte kernels need
DMA32.") then and also enable ZONE_DMA32 for LittleSur.

References:

[1] "BCM1250/BCM1125/BCM1125H User Manual", Revision 1250_1125-UM100-R,
    Broadcom Corporation, 21 Oct 2002, Section 3: "System Overview",
    "Memory Map", pp. 34-38

Signed-off-by: Maciej W. Rozycki 
Signed-off-by: Paul Burton 
Reviewed-by: Christoph Hellwig 
Patchwork: https://patchwork.linux-mips.org/patch/21107/
Fixes: cce335ae47e2 ("[MIPS] 64-bit Sibyte kernels need DMA32.")
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sasha Levin

MIPS: kexec: Relax memory restriction

2019-11-25T14:54:08+00:00

[ Upstream commit a6da4d6fdf8bd512c98d3ac7f1d16bc4bb282919 ]

We can rely on the system kernel and the dump capture kernel themselves in
memory usage.

Being restrictive with 512MB limit may cause kexec tool failure on some
platforms.

Tested-by: Rachel Mozes 
Reported-by: Rachel Mozes 
Signed-off-by: Dengcheng Zhu 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/20568/
Cc: pburton@wavecomp.com
Cc: ralf@linux-mips.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Sasha Levin

mips: txx9: fix iounmap related issue

2019-11-25T14:53:49+00:00

[ Upstream commit c6e1241a82e6e74d1ae5cc34581dab2ffd6022d0 ]

if device_register return error, iounmap should be called, also iounmap
need to call before put_device.

Signed-off-by: Ding Xiang 
Reviewed-by: Atsushi Nemoto 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/20476/
Cc: ralf@linux-mips.org
Cc: jhogan@kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sasha Levin

MIPS: BCM47XX: Enable USB power on Netgear WNDR3400v3

2019-11-25T14:53:46+00:00

[ Upstream commit feef7918667b84f9d5653c501542dd8d84ae32af ]

Setting GPIO 21 high seems to be required to enable power to USB ports
on the WNDR3400v3. As there is already similar code for WNR3500L,
make the existing USB power GPIO code generic and use that.

Signed-off-by: Tuomas Tynkkynen 
Acked-by: Hauke Mehrtens 
Signed-off-by: Paul Burton 
Patchwork: https://patchwork.linux-mips.org/patch/20259/
Cc: Rafał Miłecki 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sasha Levin

MIPS: BCM63XX: fix switch core reset on BCM6368

2019-11-16T09:27:48+00:00

commit 8a38dacf87180738d42b058334c951eba15d2d47 upstream.

The Ethernet Switch core mask was set to 0, causing the switch core to
be not reset on BCM6368 on boot. Provide the proper mask so the switch
core gets reset to a known good state.

Fixes: 799faa626c71 ("MIPS: BCM63XX: add core reset helper")
Signed-off-by: Jonas Gorski 
Signed-off-by: Paul Burton 
Cc: linux-mips@vger.kernel.org
Cc: Ralf Baechle 
Cc: James Hogan 
Cc: Florian Fainelli 
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman