linux-stable.git/arch/alpha/include, branch v4.14.331

init: Remove check_bugs() leftovers

2023-08-08T17:48:24+00:00

commit 61235b24b9cb37c13fcad5b9596d59a1afdcec30 upstream

Everything is converted over to arch_cpu_finalize_init(). Remove the
check_bugs() leftovers including the empty stubs in asm-generic, alpha,
parisc, powerpc and xtensa.

Signed-off-by: Thomas Gleixner 
Reviewed-by: Richard Henderson 
Link: https://lore.kernel.org/r/20230613224545.553215951@linutronix.de
Signed-off-by: Daniel Sneddon 
Signed-off-by: Greg Kroah-Hartman

alpha: define get_cycles macro for arch-override

2022-06-25T09:46:38+00:00

commit 1097710bc9660e1e588cf2186a35db3d95c4d258 upstream.

Alpha defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner 
Cc: Arnd Bergmann 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Acked-by: Matt Turner 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

alpha: Declare virt_to_phys and virt_to_bus parameter as pointer to volatile

2021-10-06T13:05:07+00:00

[ Upstream commit 35a3f4ef0ab543daa1725b0c963eb8c05e3376f8 ]

Some drivers pass a pointer to volatile data to virt_to_bus() and
virt_to_phys(), and that works fine.  One exception is alpha.  This
results in a number of compile errors such as

  drivers/net/wan/lmc/lmc_main.c: In function 'lmc_softreset':
  drivers/net/wan/lmc/lmc_main.c:1782:50: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

  drivers/atm/ambassador.c: In function 'do_loader_command':
  drivers/atm/ambassador.c:1747:58: error:
	passing argument 1 of 'virt_to_bus' discards 'volatile'
	qualifier from pointer target type

Declare the parameter of virt_to_phys and virt_to_bus as pointer to
volatile to fix the problem.

Signed-off-by: Guenter Roeck 
Acked-by: Arnd Bergmann 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

alpha: fix annotation of io{read,write}{16,32}be()

2020-08-26T08:29:57+00:00

[ Upstream commit bd72866b8da499e60633ff28f8a4f6e09ca78efe ]

These accessors must be used to read/write a big-endian bus.  The value
returned or written is native-endian.

However, these accessors are defined using be{16,32}_to_cpu() or
cpu_to_be{16,32}() to make the endian conversion but these expect a
__be{16,32} when none is present.  Keeping them would need a force cast
that would solve nothing at all.

So, do the conversion using swab{16,32}, like done in asm-generic for
similar situations.

Reported-by: kernel test robot 
Signed-off-by: Luc Van Oostenryck 
Signed-off-by: Andrew Morton 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Stephen Boyd 
Cc: Arnd Bergmann 
Link: http://lkml.kernel.org/r/20200622114232.80039-1-luc.vanoostenryck@gmail.com
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

Fix 'acccess_ok()' on alpha and SH

2020-06-20T08:24:58+00:00

commit 94bd8a05cd4de344a9a57e52ef7d99550251984f upstream.

Commit 594cc251fdd0 ("make 'user_access_begin()' do 'access_ok()'")
broke both alpha and SH booting in qemu, as noticed by Guenter Roeck.

It turns out that the bug wasn't actually in that commit itself (which
would have been surprising: it was mostly a no-op), but in how the
addition of access_ok() to the strncpy_from_user() and strnlen_user()
functions now triggered the case where those functions would test the
access of the very last byte of the user address space.

The string functions actually did that user range test before too, but
they did it manually by just comparing against user_addr_max().  But
with user_access_begin() doing the check (using "access_ok()"), it now
exposed problems in the architecture implementations of that function.

For example, on alpha, the access_ok() helper macro looked like this:

  #define __access_ok(addr, size) \
        ((get_fs().seg & (addr | size | (addr+size))) == 0)

and what it basically tests is of any of the high bits get set (the
USER_DS masking value is 0xfffffc0000000000).

And that's completely wrong for the "addr+size" check.  Because it's
off-by-one for the case where we check to the very end of the user
address space, which is exactly what the strn*_user() functions do.

Why? Because "addr+size" will be exactly the size of the address space,
so trying to access the last byte of the user address space will fail
the __access_ok() check, even though it shouldn't.  As a result, the
user string accessor functions failed consistently - because they
literally don't know how long the string is going to be, and the max
access is going to be that last byte of the user address space.

Side note: that alpha macro is buggy for another reason too - it re-uses
the arguments twice.

And SH has another version of almost the exact same bug:

  #define __addr_ok(addr) \
        ((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg)

so far so good: yes, a user address must be below the limit.  But then:

  #define __access_ok(addr, size)         \
        (__addr_ok((addr) + (size)))

is wrong with the exact same off-by-one case: the case when "addr+size"
is exactly _equal_ to the limit is actually perfectly fine (think "one
byte access at the last address of the user address space")

The SH version is actually seriously buggy in another way: it doesn't
actually check for overflow, even though it did copy the _comment_ that
talks about overflow.

So it turns out that both SH and alpha actually have completely buggy
implementations of access_ok(), but they happened to work in practice
(although the SH overflow one is a serious serious security bug, not
that anybody likely cares about SH security).

This fixes the problems by using a similar macro on both alpha and SH.
It isn't trying to be clever, the end address is based on this logic:

        unsigned long __ao_end = __ao_a + __ao_b - !!__ao_b;

which basically says "add start and length, and then subtract one unless
the length was zero".  We can't subtract one for a zero length, or we'd
just hit an underflow instead.

For a lot of access_ok() users the length is a constant, so this isn't
actually as expensive as it initially looks.

Reported-and-tested-by: Guenter Roeck 
Cc: Matt Turner 
Cc: Yoshinori Sato 
Signed-off-by: Linus Torvalds 
Signed-off-by: Miles Chen 
Signed-off-by: Greg Kroah-Hartman

alpha: Fix Eiger NR_IRQS to 128

2019-02-20T09:20:53+00:00

commit bfc913682464f45bc4d6044084e370f9048de9d5 upstream.

Eiger machine vector definition has nr_irqs 128, and working 2.6.26
boot shows SCSI getting IRQ-s 64 and 65. Current kernel boot fails
because Symbios SCSI fails to request IRQ-s and does not find the disks.
It has been broken at least since 3.18 - the earliest I could test with
my gcc-5.

The headers have moved around and possibly another order of defines has
worked in the past - but since 128 seems to be correct and used, fix
arch/alpha/include/asm/irq.h to have NR_IRQS=128 for Eiger.

This fixes 4.19-rc7 boot on my Force Flexor A264 (Eiger subarch).

Cc: stable@vger.kernel.org # v3.18+
Signed-off-by: Meelis Roos 
Signed-off-by: Matt Turner 
Signed-off-by: Greg Kroah-Hartman

arch/alpha, termios: implement BOTHER, IBSHIFT and termios2

2018-11-21T08:24:10+00:00

commit d0ffb805b729322626639336986bc83fc2e60871 upstream.

Alpha has had c_ispeed and c_ospeed, but still set speeds in c_cflags
using arbitrary flags. Because BOTHER is not defined, the general
Linux code doesn't allow setting arbitrary baud rates, and because
CBAUDEX == 0, we can have an array overrun of the baud_rate[] table in
drivers/tty/tty_baudrate.c if (c_cflags & CBAUD) == 037.

Resolve both problems by #defining BOTHER to 037 on Alpha.

However, userspace still needs to know if setting BOTHER is actually
safe given legacy kernels (does anyone actually care about that on
Alpha anymore?), so enable the TCGETS2/TCSETS*2 ioctls on Alpha, even
though they use the same structure. Define struct termios2 just for
compatibility; it is the exact same structure as struct termios. In a
future patchset, this will be cleaned up so the uapi headers are
usable from libc.

Signed-off-by: H. Peter Anvin (Intel) 
Cc: Jiri Slaby 
Cc: Al Viro 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Thomas Gleixner 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Eugene Syromiatnikov 
Cc: 
Cc: 
Cc: Johan Hovold 
Cc: Alan Cox 
Cc: 
Signed-off-by: Greg Kroah-Hartman

locking/xchg/alpha: Fix xchg() and cmpxchg() memory ordering bugs

2018-05-30T05:52:02+00:00

[ Upstream commit 472e8c55cf6622d1c112dc2bc777f68bbd4189db ]

Successful RMW operations are supposed to be fully ordered, but
Alpha's xchg() and cmpxchg() do not meet this requirement.

Will Deacon noticed the bug:

  > So MP using xchg:
  >
  > WRITE_ONCE(x, 1)
  > xchg(y, 1)
  >
  > smp_load_acquire(y) == 1
  > READ_ONCE(x) == 0
  >
  > would be allowed.

... which thus violates the above requirement.

Fix it by adding a leading smp_mb() to the xchg() and cmpxchg() implementations.

Reported-by: Will Deacon 
Signed-off-by: Andrea Parri 
Acked-by: Paul E. McKenney 
Cc: Alan Stern 
Cc: Andrew Morton 
Cc: Ivan Kokshaysky 
Cc: Linus Torvalds 
Cc: Matt Turner 
Cc: Peter Zijlstra 
Cc: Richard Henderson 
Cc: Thomas Gleixner 
Cc: linux-alpha@vger.kernel.org
Link: http://lkml.kernel.org/r/1519291488-5752-1-git-send-email-parri.andrea@gmail.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

locking/xchg/alpha: Add unconditional memory barrier to cmpxchg()

2018-05-30T05:52:00+00:00

[ Upstream commit cb13b424e986aed68d74cbaec3449ea23c50e167 ]

Continuing along with the fight against smp_read_barrier_depends() [1]
(or rather, against its improper use), add an unconditional barrier to
cmpxchg.  This guarantees that dependency ordering is preserved when a
dependency is headed by an unsuccessful cmpxchg.  As it turns out, the
change could enable further simplification of LKMM as proposed in [2].

[1] https://marc.info/?l=linux-kernel&m=150884953419377&w=2
    https://marc.info/?l=linux-kernel&m=150884946319353&w=2
    https://marc.info/?l=linux-kernel&m=151215810824468&w=2
    https://marc.info/?l=linux-kernel&m=151215816324484&w=2

[2] https://marc.info/?l=linux-kernel&m=151881978314872&w=2

Signed-off-by: Andrea Parri 
Acked-by: Peter Zijlstra 
Acked-by: Paul E. McKenney 
Cc: Alan Stern 
Cc: Ivan Kokshaysky 
Cc: Linus Torvalds 
Cc: Matt Turner 
Cc: Richard Henderson 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: linux-alpha@vger.kernel.org
Link: http://lkml.kernel.org/r/1519152356-4804-1-git-send-email-parri.andrea@gmail.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

alpha: Fix mixed up args in EXC macro in futex operations

2018-02-16T19:23:07+00:00

commit 84e455361ec97ea6037d31d42a2955628ea2094b upstream.

Fix the typo (mixed up arguments) in the EXC macro in the futex
definitions introduced by commit ca282f697381 (alpha: add a
helper for emitting exception table entries).

Signed-off-by: Michael Cree 
Signed-off-by: Matt Turner 
Signed-off-by: Greg Kroah-Hartman