linux-stable.git/arch/mips/include/asm/setup.h, branch linux-4.9.y

MIPS: fix fortify panic when copying asm exception handlers

2022-04-20T07:06:42+00:00

[ Upstream commit d17b66417308996e7e64b270a3c7f3c1fbd4cfc8 ]

With KCFLAGS="-O3", I was able to trigger a fortify-source
memcpy() overflow panic on set_vi_srs_handler().
Although O3 level is not supported in the mainline, under some
conditions that may've happened with any optimization settings,
it's just a matter of inlining luck. The panic itself is correct,
more precisely, 50/50 false-positive and not at the same time.
From the one side, no real overflow happens. Exception handler
defined in asm just gets copied to some reserved places in the
memory.
But the reason behind is that C code refers to that exception
handler declares it as `char`, i.e. something of 1 byte length.
It's obvious that the asm function itself is way more than 1 byte,
so fortify logics thought we are going to past the symbol declared.
The standard way to refer to asm symbols from C code which is not
supposed to be called from C is to declare them as
`extern const u8[]`. This is fully correct from any point of view,
as any code itself is just a bunch of bytes (including 0 as it is
for syms like _stext/_etext/etc.), and the exact size is not known
at the moment of compilation.
Adjust the type of the except_vec_vi_*() and related variables.
Make set_handler() take `const` as a second argument to avoid
cast-away warnings and give a little more room for optimization.

Signed-off-by: Alexander Lobakin 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

MIPS: KVM: Don't hardcode restored HWREna

2016-06-15T21:58:31+00:00

KVM modifies CP0_HWREna during guest execution so it can trap and
emulate RDHWR instructions, however it always restores the hardcoded
value 0x2000000F. This assumes the presence of the UserLocal register,
and the absence of any implementation dependent or future HW registers.

Fix by exporting the value that traps.c write into CP0_HWREna, and
loading from there instead of hard coding.

Signed-off-by: James Hogan 
Acked-by: Ralf Baechle 
Cc: Paolo Bonzini 
Cc: Radim Krčmář 
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini

MIPS: Add 8250/16550 serial early printk driver

2013-10-29T20:24:36+00:00

Signed-off-by: Yoichi Yuasa 
Cc: linux-mips 
Patchwork: https://patchwork.linux-mips.org/patch/947/
Signed-off-by: Ralf Baechle

UAPI: (Scripted) Disintegrate arch/mips/include/asm

2012-10-09T08:47:14+00:00

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann 
Acked-by: Thomas Gleixner 
Acked-by: Michael Kerrisk 
Acked-by: Paul E. McKenney 
Acked-by: Dave Jones

MIPS: Move cache setup to setup_arch().

2012-05-16T21:34:34+00:00

commit 97ce2c88f9ad42e3c60a9beb9fca87abf3639faa (jump-label: initialize
jump-label subsystem much earlier) breaks MIPS.  The jump_label_init()
call was moved before trap_init() which is where we initialize
flush_icache_range().

In order to be good citizens, we move cache initialization earlier so
that we don't jump through a null flush_icache_range function pointer
when doing the jump label initialization.

Signed-off-by: David Daney 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3822/
Signed-off-by: Ralf Baechle

Disintegrate asm/system.h for MIPS

2012-03-28T17:30:02+00:00

Disintegrate asm/system.h for MIPS.

Signed-off-by: David Howells 
Acked-by: Ralf Baechle 
cc: linux-mips@linux-mips.org

MIPS: Extend COMMAND_LINE_SIZE

2009-11-02T11:00:01+00:00

Some firmware may pass well over 256 bytes these days.

Signed-off-by: Ralf Baechle

MIPS: Move headfiles to new location below arch/mips/include

2008-10-11T15:18:52+00:00

Signed-off-by: Ralf Baechle