Paul Burton [Sat, 17 Jun 2017 20:52:46 +0000 (13:52 -0700)]
dt-bindings: Document img,boston-clock binding
Add device tree binding documentation for the clocks provided by the
MIPS Boston development board from Imagination Technologies, and a
header file describing the available clocks for use by device trees &
driver.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Michael Turquette <mturquette@baylibre.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: devicetree@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16482/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Thu, 29 Jun 2017 09:12:36 +0000 (10:12 +0100)]
MIPS: Traced negative syscalls should return -ENOSYS
If a negative system call number is used when system call tracing is
enabled, syscall_trace_enter() will return that negative system call
number without having written the return value and error flag into the
pt_regs.
The caller then treats it as a cancelled system call and assumes that
the return value and error flag are already written, leaving the
negative system call number in the return register ($v0), and the 4th
system call argument in the error register ($a3).
Add a special case to detect this at the end of syscall_trace_enter(),
to set the return value to error -ENOSYS when this happens.
Fixes: d218af78492a ("MIPS: scall: Always run the seccomp syscall filters") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16653/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Thu, 29 Jun 2017 09:12:35 +0000 (10:12 +0100)]
MIPS: Correct forced syscall errors
When the system call return value is forced to be an error (for example
due to SECCOMP_RET_ERRNO), syscall_set_return_value() puts the error
code in the return register $v0 and -1 in the error register $a3.
However normally executed system calls put 1 in the error register
rather than -1, so fix syscall_set_return_value() to be consistent with
that.
I don't anticipate that anything would have been broken by this, since
the most natural way to check the error register on MIPS would be a
conditional branch if error register is [not] equal to zero (bnez or
beqz).
Fixes: 1d7bf993e073 ("MIPS: ftrace: Add support for syscall tracepoints.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16652/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Thu, 29 Jun 2017 09:12:34 +0000 (10:12 +0100)]
MIPS: Negate error syscall return in trace
The sys_exit trace event takes a single return value for the system
call, which MIPS passes the value of the $v0 (result) register, however
MIPS returns positive error codes in $v0 with $a3 specifying that $v0
contains an error code. As a result erroring system calls are traced
returning positive error numbers that can't always be distinguished from
success.
Use regs_return_value() to negate the error code if $a3 is set.
Fixes: 1d7bf993e073 ("MIPS: ftrace: Add support for syscall tracepoints.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 3.13+
Patchwork: https://patchwork.linux-mips.org/patch/16651/ Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Thu, 29 Jun 2017 09:12:33 +0000 (10:12 +0100)]
MIPS: Drop duplicate HAVE_SYSCALL_TRACEPOINTS select
MIPS selects HAVE_SYSCALL_TRACEPOINTS twice. The first was added back in
v3.13 by commit 2d7bf993e073 ("MIPS: ftrace: Add support for syscall
tracepoints."), but then a second redundant one was added in v4.2 by
commit fb59e394c30c ("MIPS: ftrace: Enable support for syscall
tracepoints.").
Drop the duplicate select.
Fixes: fb59e394c30c ("MIPS: ftrace: Enable support for syscall tracepoints.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16654/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: MIPS16e2: Report ASE presence in /proc/cpuinfo
Only now that both feature determination and unaligned emulation is in
place add reporting to /proc/cpuinfo, so that the presence of "mips16e2"
there not only indicates our recognition of the hardware feature, but
correct unaligned emulation as well.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16757/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Implement extended LWSP/SWSP instruction subdecoding for the purpose of
unaligned GP-relative memory access emulation.
With the introduction of the MIPS16e2 ASE[1] the previously must-be-zero
3-bit field at bits 7..5 of the extended encodings of the instructions
selected with the LWSP and SWSP major opcodes has become a `sel' field,
acting as an opcode extension for additional operations. In both cases
the `sel' value of 0 has retained the original operation, that is:
LW rx, offset(sp)
and:
SW rx, offset(sp)
for LWSP and SWSP respectively. In hardware predating the MIPS16e2 ASE
other values may or may not have been decoded, architecturally yielding
unpredictable results, and in our unaligned memory access emulation we
have treated the 3-bit field as a don't-care, that is effectively making
all the possible encodings of the field alias to the architecturally
defined encoding of 0.
For the non-zero values of the `sel' field the MIPS16e2 ASE has in
particular defined these GP-relative operations:
LW rx, offset(gp) # sel = 1
LH rx, offset(gp) # sel = 2
LHU rx, offset(gp) # sel = 4
and
SW rx, offset(gp) # sel = 1
SH rx, offset(gp) # sel = 2
for LWSP and SWSP respectively, which will trap with an Address Error
exception if the effective address calculated is not naturally-aligned
for the operation requested. These operations have been selected for
unaligned access emulation, for consistency with the corresponding
regular MIPS and microMIPS operations.
For other non-zero values of the `sel' field the MIPS16e2 ASE has
defined further operations, which however either never trap with an
Address Error exception, such as LWL or GP-relative SB, or are not
supposed to be emulated, such as LL or SC. These operations have been
selected to exclude from unaligned access emulation, should an Address
Error exception ever happen with them.
Subdecode the `sel' field in unaligned access emulation then for the
extended encodings of the instructions selected with the LWSP and SWSP
major opcodes, whenever support for the MIPS16e2 ASE has been detected
in hardware, and either emulate the operation requested or send SIGBUS
to the originating process, according to the selection described above.
For hardware implementing the MIPS16 ASE, however lacking MIPS16e2 ASE
support retain the original interpretation of the `sel' field.
The effects of this change are illustrated with the following user
program:
which shows that for GP-relative operations the correct trapping address
calculated from $gp has been obtained from the CP0 BadVAddr register and
so has data from the source operand, however masking and extension has
not been applied for halfword operations.
With the change applied and interAptive MR2 hardware the program
produces the following output:
Goran Ferenc [Wed, 28 Jun 2017 15:55:30 +0000 (17:55 +0200)]
MIPS: VDSO: Add implementation of gettimeofday() fallback
This patch adds gettimeofday_fallback() function that wraps assembly
invocation of gettimeofday() syscall using __NR_gettimeofday.
This function is used if pure VDSO implementation gettimeofday()
does not succeed for any reason. Its imeplementation is enclosed in
"#ifdef CONFIG_MIPS_CLOCK_VSYSCALL" to be in sync with the similar
arrangement for __vdso_gettimeofday().
If syscall invocation via __NR_gettimeofday fails, register a3 will
be set. So, after the syscall, register a3 is tested and the return
valuem is negated if it's set.
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16640/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Goran Ferenc [Wed, 28 Jun 2017 15:55:29 +0000 (17:55 +0200)]
MIPS: VDSO: Add implementation of clock_gettime() fallback
This patch adds clock_gettime_fallback() function that wraps assembly
invocation of clock_gettime() syscall using __NR_clock_gettime.
This function is used if pure VDSO implementation of clock_gettime()
does not succeed for any reason. For example, it is called if the
clkid parameter of clock_gettime() is not one of the clkids listed
in the switch-case block of the function __vdso_clock_gettime()
(one such case for clkid is CLOCK_BOOTIME).
If syscall invocation via __NR_clock_gettime fails, register a3 will
be set. So, after the syscall, register a3 is tested and the return
value is negated if it's set.
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16639/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Goran Ferenc [Wed, 28 Jun 2017 15:55:28 +0000 (17:55 +0200)]
MIPS: VDSO: Fix conversions in do_monotonic()/do_monotonic_coarse()
Fix incorrect calculation in do_monotonic() and do_monotonic_coarse()
function that in turn caused incorrect values returned by the vdso
version of system call clock_gettime() on mips64 if its system clock
ID parameter was CLOCK_MONOTONIC or CLOCK_MONOTONIC_COARSE.
Consider these variables and their types on mips32 and mips64:
For mips64 case, u32 vdso_data.wall_to_mono_sec variable is updated
from the 64-bit signed variable tk->wall_to_monotonic.tv_sec
(kernel/vdso.c:76) which is a negative number holding the time passed
from 1970-01-01 to the time boot started. This 64-bit signed value is
currently around 47+ years, in seconds. For instance, let this value
be:
By updating 32-bit vdso_data.wall_to_mono_sec variable, we lose upper
32 bits (signed 1's).
to_mono_sec variable is a parameter of do_monotonic() and
do_monotonic_coarse() functions which holds vdso_data.wall_to_mono_sec
value. Its value needs to be added (or subtracted considering it holds
negative value from the tk->wall_to_monotonic.tv_sec) to the current
time passed from 1970-01-01 (ts->tv_sec), which is again something like
47+ years, but increased by the time passed from the boot to the
current time. ts->tv_sec is 32-bit long in case of 32-bit architecture
and 64-bit long in case of 64-bit architecture. Consider the update of
ts->tv_sec (vdso/gettimeofday.c:55 & 167):
ts->tv_sec += to_mono_sec;
mips32 case: This update will be performed correctly, since both
ts->tv_sec and to_mono_sec are 32-bit long and the sign in to_mono_sec
is preserved. Implicit conversion from u32 to s32 will be done
correctly.
mips64 case: This update will be wrong, since the implicit conversion
will not be done correctly. The reason is that the conversion will be
from u32 to s64. This is because to_mono_sec is 32-bit long for both
mips32 and mips64 cases and s64..33 bits of converted to_mono_sec
variable will be zeros.
So, in order to make MIPS64 implementation work properly for
MONOTONIC and MONOTONIC_COARSE clock ids on mips64, the size of
wall_to_mono_sec variable in mips_vdso_data union and respective
parameters in do_monotonic() and do_monotonic_coarse() functions
should be changed from u32 to u64. Because of consistency, this
size change from u32 and u64 is also done for wall_to_mono_nsec
variable and corresponding function parameters.
As far as similar situations for other architectures are concerned,
let's take a look at arm. Arm has two distinct vdso_data structures
for 32-bit & 64-bit cases, and arm's wall_to_mono_sec and
wall_to_mono_nsec are u32 for 32-bit and u64 for 64-bit cases.
On the other hand, MIPS has only one structure (mips_vdso_data),
hence the need for changing the size of above mentioned parameters.
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> Cc: Douglas Leung <douglas.leung@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Petar Jovanovic <petar.jovanovic@imgtec.com> Cc: Raghu Gandham <raghu.gandham@imgtec.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16638/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Fri, 2 Jun 2017 22:38:04 +0000 (15:38 -0700)]
MIPS: Use current_cpu_type() in m4kc_tlbp_war()
Use current_cpu_type() to check for 4Kc processors instead of checking
the PRID directly. This will allow for the 4Kc case to be optimised out
of kernels that can't run on 4KC processors, thanks to __get_cpu_type()
and its unreachable() call.
Paul Burton [Fri, 2 Jun 2017 22:38:03 +0000 (15:38 -0700)]
MIPS: Allow storing pgd in C0_CONTEXT for MIPSr6
CONFIG_MIPS_PGD_C0_CONTEXT, which allows a pointer to the page directory
to be stored in the cop0 Context register when enabled, was previously
only allowed for MIPSr2. MIPSr6 is just as able to make use of it, so
allow it there too.
Paul Burton [Fri, 2 Jun 2017 22:38:02 +0000 (15:38 -0700)]
MIPS: Handle tlbex-tlbp race condition
In systems where there are multiple actors updating the TLB, the
potential exists for a race condition wherein a CPU hits a TLB exception
but by the time it reaches a TLBP instruction the affected TLB entry may
have been replaced. This can happen if, for example, a CPU shares the
TLB between hardware threads (VPs) within a core and one of them
replaces the entry that another has just taken a TLB exception for.
We handle this race in the case of the Hardware Table Walker (HTW) being
the other actor already, but didn't take into account the potential for
multiple threads racing. Include the code for aborting TLB exception
handling in affected multi-threaded systems, those being the I6400 &
I6500 CPUs which share TLB entries between VPs.
In the case of using RiXi without dedicated exceptions we have never
handled this race even for HTW. This patch adds WARN()s to these cases
which ought never to be hit because all CPUs with either HTW or shared
FTLB RAMs also include dedicated RiXi exceptions, but the WARN()s will
ensure this is always the case.
Paul Burton [Fri, 2 Jun 2017 22:38:01 +0000 (15:38 -0700)]
MIPS: Add CPU shared FTLB feature detection
Some systems share FTLB RAMs or entries between sibling CPUs (ie.
hardware threads, or VP(E)s, within a core). These properties require
kernel handling in various places. As a start this patch introduces
cpu_has_shared_ftlb_ram & cpu_has_shared_ftlb_entries feature macros
which we set appropriately for I6400 & I6500 CPUs. Further patches will
make use of these macros as appropriate.
Paul Burton [Fri, 2 Jun 2017 21:48:55 +0000 (14:48 -0700)]
MIPS: CPS: Handle spurious VP starts more gracefully
On pre-r6 systems with the MT ASE the CPS SMP code included checks to
halt the VPE running mips_cps_boot_vpes() if its bit in the struct
core_boot_config vpe_mask field is clear. This was largely done in order
to allow us to start arbitrary VPEs within a core despite the fact that
hardware is typically configured to run only VPE0 after powering up a
core. VPE0 would start the desired other VPEs, halt itself, and the fact
that VPE0 started would be largely hidden & irrelevant.
In MIPSr6 multithreading we have control over which VPs start executing
when a core powers up via the cores CPC registers accessed remotely
through the redirect block. For this reason the MIPSr6 multithreading
path in mips_cps_boot_vpes() hasn't bothered up until now to handle
halting the VP running it.
However it is possible to power up cores entirely in hardware by using a
pwr_up pin associated with the core. Unfortunately some systems wire
this pin to a logic 1, which means that it is possible for a core to
power up at a point that software doesn't expect. The result is that we
generally go execute the kernel on a CPU that ought not to be running &
the results can be unpredictable.
Handle this case by stopping VPs that we don't expect to be running in
mips_cps_boot_vpes() - with this change even if a core powers up it will
do nothing useful & all VPs within it will stop running before they
proceed to run general kernel code & do any damage. Ideally we would
produce some sort of warning here, but given the stage of core bringup
this happens at that would be non-trivial. We also will only hit this if
a core starts up after being offlined via hotplug, and when that happens
we will already produce a warning that the CPU didn't power down in
cps_cpu_die() which seems sufficient.
Paul Burton [Fri, 2 Jun 2017 21:48:54 +0000 (14:48 -0700)]
MIPS: CPS: Handle cores not powering down more gracefully
If we get into a state where a core that ought to power down isn't doing
so then the current result is that another CPU gets stuck inside
cps_cpu_die() waiting for CPU that ought to be powering down to do so.
The best case scenario is that we then trigger RCU stall messages or
lockup messages, but neither makes it particularly clear what's
happening.
Handle this more gracefully by introducing a timeout beyond which we
warn the user that the core didn't power down & stop waiting for it.
This at least allows the CPU running cps_cpu_die() to continue normally,
and hopefully presuming the CPU that powered back up is doing nothing
harmful the system will continue functioning as normal.
Paul Burton [Fri, 2 Jun 2017 21:48:53 +0000 (14:48 -0700)]
MIPS: CPS: Prevent multi-core with dcache aliasing
Systems using the MIPS Coherence Manager (CM) cannot support multi-core
SMP with dcache aliasing. This is because CPU caches are VIPT, but
interventions in CM-based systems provide only the physical address to
remote caches. This means that interventions may behave incorrectly in
the presence of an aliasing dcache, since the physical address used
when handling an intervention may lead to operation on an aliased cache
line rather than the correct line.
Prevent us from running into this issue by refusing to boot secondary
cores in systems where dcache aliasing may occur.
Paul Burton [Fri, 2 Jun 2017 21:48:52 +0000 (14:48 -0700)]
MIPS: CPS: Select CONFIG_SYS_SUPPORTS_SCHED_SMT for MIPSr6
Prior to MIPSr6 multithreading is only supported if CONFIG_MIPS_MT_SMP
is enabled, so CONFIG_MIPS_MT_SMP selects CONFIG_SYS_SUPPORTS_SCHED_SMT.
With MIPSr6 the CONFIG_MIPS_CPS SMP implementation always supports
multithreading, so have it select CONFIG_SYS_SUPPORTS_SCHED_SMT in order
to allow the scheduler to make better informed decisions on
multithreaded MIPSr6 systems (for example those using I6400 or I6500
CPUs).
Paul Burton [Fri, 2 Jun 2017 21:48:51 +0000 (14:48 -0700)]
MIPS: CM: WARN on attempt to lock invalid VP, not BUG
Rather than using BUG_ON in the case of an invalid attempt to lock
access to a non-zero VP on a pre-CM3 system, use WARN_ON so that we have
even the slightest chance of recovery.
Paul Burton [Fri, 2 Jun 2017 21:48:50 +0000 (14:48 -0700)]
MIPS: CM: Avoid per-core locking with CM3 & higher
CM3 provides a GCR_CL_OTHER register per VP, rather than only per core.
This means that we don't need to prevent other VPs within a core from
racing with code that makes use of the core-other register region.
Reduce locking overhead by demoting the per-core spinlock providing
protection for CM2.5 & lower to a per-CPU/per-VP spinlock for CM3 &
higher.
MIPS: Use `pr_debug' for messages from `__compute_return_epc_for_insn'
Reduce the log level for branch emulation error messages issued before
sending SIGILL by `__compute_return_epc_for_insn' as these are triggered
by user software and are not an event that would normally require any
attention. The same signal sent from elsewhere does not actually leave
any trace in the kernel log at all.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16402/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: For MFHC1/MTHC1 also return SIGILL right away
Update commit 1ac944007bed ("MIPS: math-emu: Add mfhc1 & mthc1
support.") and like done throughout `cop1Emulate' for other cases also
for the MFHC1 and MTHC1 instructions return SIGILL right away rather
than jumping to a single `return' statement.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16401/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Fix a typo: s/preset/present/ in r2-to-r6 emulation error message
This is a user-visible message, so we want it to be spelled correctly.
Fixes: 5f9f41c474be ("MIPS: kernel: Prepare the JR instruction for emulation on MIPS R6") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16400/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Send SIGILL for R6 branches in `__compute_return_epc_for_insn'
Fix:
* commit 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact
(BC) instruction"),
* commit 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC
instruction"),
* commit 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC
instructions"),
* commit 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC
instructions"),
* commit c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and
BEQZALC instructions")
and send SIGILL rather than returning -SIGILL for R6 branch and jump
instructions. Returning -SIGILL is never correct as the API defines
this function's result upon error to be -EFAULT and a signal actually
issued.
Fixes: 8467ca0122e2 ("MIPS: Emulate the new MIPS R6 branch compact (BC) instruction") Fixes: 84fef630127a ("MIPS: Emulate the new MIPS R6 BALC instruction") Fixes: 69b9a2fd05a3 ("MIPS: Emulate the new MIPS R6 BEQZC and JIC instructions") Fixes: 28d6f93d201d ("MIPS: Emulate the new MIPS R6 BNEZC and JIALC instructions") Fixes: c893ce38b265 ("MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16399/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Send SIGILL for linked branches in `__compute_return_epc_for_insn'
Fix commit 319824eabc3f ("MIPS: kernel: branch: Do not emulate the
branch likelies on MIPS R6") and also send SIGILL rather than returning
-SIGILL for BLTZAL, BLTZALL, BGEZAL and BGEZALL instruction encodings no
longer supported in R6, except where emulated. Returning -SIGILL is
never correct as the API defines this function's result upon error to be
-EFAULT and a signal actually issued.
Fixes: 319824eabc3f ("MIPS: kernel: branch: Do not emulate the branch likelies on MIPS R6") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16398/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Rename `sigill_r6' to `sigill_r2r6' in `__compute_return_epc_for_insn'
Use the more accurate `sigill_r2r6' name for the label used in the case
of sending SIGILL in the absence of the instruction emulator for an
earlier ISA level instruction that has been removed as from the R6 ISA,
so that the `sigill_r6' name is freed for the situation where an R6
instruction is not supposed to be interpreted, because the executing
processor does not support the R6 ISA.
Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.19+
Patchwork: https://patchwork.linux-mips.org/patch/16397/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Send SIGILL for BPOSGE32 in `__compute_return_epc_for_insn'
Fix commit e50c0a8fa60d ("Support the MIPS32 / MIPS64 DSP ASE.") and
send SIGILL rather than SIGBUS whenever an unimplemented BPOSGE32 DSP
ASE instruction has been encountered in `__compute_return_epc_for_insn'
as our Reserved Instruction exception handler would in response to an
attempt to actually execute the instruction. Sending SIGBUS only makes
sense for the unaligned PC case, since moved to `__compute_return_epc'.
Adjust function documentation accordingly, correct formatting and use
`pr_info' rather than `printk' as the other exit path already does.
Fixes: e50c0a8fa60d ("Support the MIPS32 / MIPS64 DSP ASE.") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 2.6.14+
Patchwork: https://patchwork.linux-mips.org/patch/16396/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Fix unaligned PC interpretation in `compute_return_epc'
Fix a regression introduced with commit fb6883e5809c ("MIPS: microMIPS:
Support handling of delay slots.") and defer to `__compute_return_epc'
if the ISA bit is set in EPC with non-MIPS16, non-microMIPS hardware,
which will then arrange for a SIGBUS due to an unaligned instruction
reference. Returning EPC here is never correct as the API defines this
function's result to be either a negative error code on failure or one
of 0 and BRANCH_LIKELY_TAKEN on success.
Fixes: fb6883e5809c ("MIPS: microMIPS: Support handling of delay slots.") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.9+
Patchwork: https://patchwork.linux-mips.org/patch/16395/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Actually decode JALX in `__compute_return_epc_for_insn'
Complement commit fb6883e5809c ("MIPS: microMIPS: Support handling of
delay slots.") and actually decode the regular MIPS JALX major
instruction opcode, the handling of which has been added with the said
commit for EPC calculation in `__compute_return_epc_for_insn'.
Fixes: fb6883e5809c ("MIPS: microMIPS: Support handling of delay slots.") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.9+
Patchwork: https://patchwork.linux-mips.org/patch/16394/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: math-emu: Prevent wrong ISA mode instruction emulation
Terminate FPU emulation immediately whenever an ISA mode switch has been
observed. This is so that we do not interpret machine code in the wrong
mode, for example when a regular MIPS FPU instruction has been placed in
a delay slot of a jump that switches into the MIPS16 mode, as with the
following code (taken from a GCC test suite case):
Here `set_fast_math' is called from `40130e' (`40130f' with the ISA bit)
and emulation triggers for the CTC1 instruction. As it is in a jump
delay slot emulation continues from `401312' (`401313' with the ISA
bit). However we have no path to handle MIPS16 FPU code emulation,
because there are no MIPS16 FPU instructions. So the default emulation
path is taken, interpreting a 32-bit word fetched by `get_user' from
`401313' as a regular MIPS instruction, which is:
This makes the FPU emulator proceed with the supposed SDC1 instruction
and consequently makes the program considered here terminate with
SIGSEGV.
A similar although less severe issue exists with pure-microMIPS
processors in the case where similarly an FPU instruction is emulated in
a delay slot of a register jump that (incorrectly) switches into the
regular MIPS mode. A subsequent instruction fetch from the jump's
target is supposed to cause an Address Error exception, however instead
we proceed with regular MIPS FPU emulation.
For simplicity then, always terminate the emulation loop whenever a mode
change is detected, denoted by an ISA mode bit flip. As from commit 377cb1b6c16a ("MIPS: Disable MIPS16/microMIPS crap for platforms not
supporting these ASEs.") the result of `get_isa16_mode' can be hardcoded
to 0, so we need to examine the ISA mode bit by hand.
This complements commit 102cedc32a6e ("MIPS: microMIPS: Floating point
support.") which added JALX decoding to FPU emulation.
Fixes: 102cedc32a6e ("MIPS: microMIPS: Floating point support.") Signed-off-by: Maciej W. Rozycki <macro@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org # 3.9+
Patchwork: https://patchwork.linux-mips.org/patch/16393/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Sat, 10 Jun 2017 00:26:43 +0000 (17:26 -0700)]
MIPS: Use queued spinlocks (qspinlock)
This patch switches MIPS to make use of generically implemented queued
spinlocks, rather than the ticket spinlocks used previously. This allows
us to drop a whole load of inline assembly, share more generic code, and
is also a performance win.
Results from running the AIM7 short workload on a MIPS Creator Ci40 (ie.
2 core 2 thread interAptiv CPU clocked at 546MHz) with v4.12-rc4
pistachio_defconfig, with ftrace disabled due to a current bug, and both
with & without use of queued rwlocks & spinlocks:
The kernels used for these tests also had my "MIPS: Hardcode cpu_has_*
where known at compile time due to ISA" patch applied, which allows the
kernel_uses_llsc checks in cmpxchg() & xchg() to be optimised away at
compile time.
Paul Burton [Sat, 10 Jun 2017 00:26:42 +0000 (17:26 -0700)]
MIPS: Use queued read/write locks (qrwlock)
This patch switches MIPS to make use of generically implemented queued
read/write locks, rather than the custom implementation used previously.
This allows us to drop a whole load of inline assembly, share more
generic code, and is also a performance win.
Results from running the AIM7 short workload on a MIPS Creator Ci40 (ie.
2 core 2 thread interAptiv CPU clocked at 546MHz) with v4.12-rc4
pistachio_defconfig, with ftrace disabled due to a current bug, and both
with & without use of queued rwlocks & spinlocks:
The kernels used for these tests also had my "MIPS: Hardcode cpu_has_*
where known at compile time due to ISA" patch applied, which allows the
kernel_uses_llsc checks in cmpxchg() & xchg() to be optimised away at
compile time.
Paul Burton [Sat, 10 Jun 2017 00:26:41 +0000 (17:26 -0700)]
MIPS: cmpxchg: Rearrange __xchg() arguments to match xchg()
The __xchg() function declares its first 2 arguments in reverse order
compared to the xchg() macro, which is confusing & serves no purpose.
Reorder the arguments such that __xchg() & xchg() match.
Implement support for 1 & 2 byte cmpxchg() using read-modify-write atop
a 4 byte cmpxchg(). This allows us to support these atomic operations
despite the MIPS ISA only providing 4 & 8 byte atomic operations.
This is required in order to support queued rwlocks (qrwlock) in a later
patch, since these make use of a 1 byte cmpxchg() in their slow path.
Paul Burton [Sat, 10 Jun 2017 00:26:39 +0000 (17:26 -0700)]
MIPS: cmpxchg: Implement 1 byte & 2 byte xchg()
Implement 1 & 2 byte xchg() using read-modify-write atop a 4 byte
cmpxchg(). This allows us to support these atomic operations despite the
MIPS ISA only providing for 4 & 8 byte atomic operations.
This is required in order to support queued spinlocks (qspinlock) in a
later patch, since these make use of a 2 byte xchg() in their slow path.
Paul Burton [Sat, 10 Jun 2017 00:26:38 +0000 (17:26 -0700)]
MIPS: cmpxchg: Implement __cmpxchg() as a function
Replace the macro definition of __cmpxchg() with an inline function,
which is easier to read & modify. The cmpxchg() & cmpxchg_local() macros
are adjusted to call the new __cmpxchg() function.
Paul Burton [Sat, 10 Jun 2017 00:26:36 +0000 (17:26 -0700)]
MIPS: cmpxchg: Error out on unsupported xchg() calls
xchg() has up until now simply returned the x parameter in cases where
it is called with a pointer to a value of an unsupported size. This will
often cause the calling code to hit a failure path, presuming that the
value of x differs from the content of the memory pointed at by ptr, but
we can do better by producing a compile-time or link-time error such
that unsupported calls to xchg() are detectable earlier than runtime.
This patch does this in the same was as is already done for cmpxchg(),
using a call to a missing function annotated with __compiletime_error().
Paul Burton [Sat, 10 Jun 2017 00:26:35 +0000 (17:26 -0700)]
MIPS: cmpxchg: Use __compiletime_error() for bad cmpxchg() pointers
Our cmpxchg() implementation relies upon generating a call to a function
which doesn't really exist (__cmpxchg_called_with_bad_pointer) to create
a link failure in cases where cmpxchg() is called with a pointer to a
value of an unsupported size.
The __compiletime_error macro can be used to decorate a function such
that a call to it generates a compile-time, rather than a link-time,
error. This patch uses __compiletime_error to cause bad cmpxchg() calls
to error out at compile time rather than link time, allowing errors to
occur more quickly & making it easier to spot where the problem comes
from.
Paul Burton [Sat, 10 Jun 2017 00:26:34 +0000 (17:26 -0700)]
MIPS: cmpxchg: Pull xchg() asm into a macro
Use a macro to generate the 32 & 64 bit variants of the backing code for
xchg(), much as is already done for cmpxchg(). This removes the
duplication that could previously be found in __xchg_u32() &
__xchg_u64().
Prior to this patch the xchg & cmpxchg functions have duplicated code
which is for all intents & purposes identical apart from use of a
branch-likely instruction in the R10000_LLSC_WAR case & a regular branch
instruction in the non-R10000_LLSC_WAR case.
This patch removes the duplication, declaring a __scbeqz macro to select
the branch instruction suitable for use when checking the result of an
sc instruction & making use of it to unify the 2 cases.
In __xchg_u{32,64}() this means writing the branch in asm, where it was
previously being done in C as a do...while loop for the
non-R10000_LLSC_WAR case. As this is a single instruction, and adds
consistency with the R10000_LLSC_WAR cases & the cmpxchg() code, this
seems worthwhile.
Miodrag Dinic [Mon, 19 Jun 2017 15:50:11 +0000 (17:50 +0200)]
MIPS: unaligned: Add DSP lwx & lhx missaligned access support
Add handling of missaligned access for DSP load instructions
lwx & lhx.
Since DSP instructions share SPECIAL3 opcode with other non-DSP
instructions, necessary logic was inserted for distinguishing
between instructions with SPECIAL3 opcode. For that purpose,
the instruction format for DSP instructions is added to
arch/mips/include/uapi/asm/inst.h.
Leonid Yegoshin [Mon, 19 Jun 2017 15:50:10 +0000 (17:50 +0200)]
MIPS: R6: Fix PREF instruction usage by memcpy for MIPS R6
Disable usage of PREF instruction usage by memcpy for MIPS R6.
MIPS R6 redefines PREF instruction with smaller offset than
ordinary MIPS. However, the memcpy code uses PREF instruction
with offsets bigger than +-256 bytes.
Malta kernels already disable usage of PREF for memcpy.
This was found during adaptation of MIPS R6 for virtual board
used by Android emulator.
Miodrag Dinic [Mon, 19 Jun 2017 15:50:09 +0000 (17:50 +0200)]
MIPS: build: Fix "-modd-spreg" switch usage when compiling for mips32r6
Add "-modd-spreg" when compiling the kernel for mips32r6 target.
This makes sure the kernel builds properly even with toolchains that
use "-mno-odd-spreg" by default. This is the case with Android gcc.
Prior to this patch, kernel builds using gcc for Android failed with
following error messages, if target architecture is set to mips32r6:
arch/mips/kernel/r4k_switch.S: Assembler messages:
.../r4k_switch.S:210: Error: float register should be even, was 1
.../r4k_switch.S:212: Error: float register should be even, was 3
.../r4k_switch.S:214: Error: float register should be even, was 5
.../r4k_switch.S:216: Error: float register should be even, was 7
.../r4k_switch.S:218: Error: float register should be even, was 9
.../r4k_switch.S:220: Error: float register should be even, was 11
.../r4k_switch.S:222: Error: float register should be even, was 13
.../r4k_switch.S:224: Error: float register should be even, was 15
.../r4k_switch.S:226: Error: float register should be even, was 17
.../r4k_switch.S:228: Error: float register should be even, was 19
.../r4k_switch.S:230: Error: float register should be even, was 21
.../r4k_switch.S:232: Error: float register should be even, was 23
.../r4k_switch.S:234: Error: float register should be even, was 25
.../r4k_switch.S:236: Error: float register should be even, was 27
.../r4k_switch.S:238: Error: float register should be even, was 29
.../r4k_switch.S:240: Error: float register should be even, was 31
make[2]: *** [arch/mips/kernel/r4k_switch.o] Error 1
Miodrag Dinic [Mon, 19 Jun 2017 15:50:08 +0000 (17:50 +0200)]
MIPS: cmdline: Add support for 'memmap' parameter
Implement support for parsing 'memmap' kernel command line parameter.
This patch covers parsing of the following two formats for 'memmap'
parameter values:
- nn[KMG]@ss[KMG]
- nn[KMG]$ss[KMG]
([KMG] = K M or G (kilo, mega, giga))
These two allowed formats for parameter value are already documented
in file kernel-parameters.txt in Documentation/admin-guide folder.
Some architectures already support them, but Mips did not prior to
this patch.
Excerpt from Documentation/admin-guide/kernel-parameters.txt:
memmap=nn[KMG]@ss[KMG]
[KNL] Force usage of a specific region of memory.
Region of memory to be used is from ss to ss+nn.
memmap=nn[KMG]$ss[KMG]
Mark specific memory as reserved.
Region of memory to be reserved is from ss to ss+nn.
Example: Exclude memory from 0x18690000-0x1869ffff
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
There is no need to update this documentation file with respect to
this patch.
Huacai Chen [Thu, 22 Jun 2017 15:06:54 +0000 (23:06 +0800)]
MIPS: Loogson: Make enum loongson_cpu_type more clear
Sort enum loongson_cpu_type in a more reasonable manner, this makes the
CPU names more clear and extensible. Those already defined enum values
are renamed to Legacy_* for compatibility.
Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: John Crispin <john@phrozen.org> Cc: Steven J . Hill <Steven.Hill@cavium.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16591/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Huacai Chen [Thu, 22 Jun 2017 15:06:52 +0000 (23:06 +0800)]
MIPS: Loongson-3: IRQ balancing for PCI devices
IRQ0 (HPET), IRQ1 (Keyboard), IRQ2 (Cascade), IRQ7 (SCI), IRQ8 (RTC)
and IRQ12 (Mouse) are handled by core-0 locally. Other PCI IRQs (3, 4,
5, 6, 14, 15) are balanced by all cores from Node-0. This can improve
I/O performance significantly.
Signed-off-by: Huacai Chen <chenhc@lemote.com> Cc: John Crispin <john@phrozen.org> Cc: Steven J . Hill <Steven.Hill@cavium.com> Cc: Fuxin Zhang <zhangfx@lemote.com> Cc: Zhangjin Wu <wuzhangjin@gmail.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16589/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Fri, 2 Jun 2017 19:29:59 +0000 (12:29 -0700)]
MIPS: SEAD-3: Fix GIC interrupt specifiers
The various interrupt specifiers in the device tree are not in a valid
format for the MIPS GIC interrupt controller binding. Where each
interrupt should provide 3 values - GIC_LOCAL or GIC_SHARED, the
pin number & the type of interrupt - the device tree was only providing
the pin number. This causes interrupts for those devices to not be used
when a GIC is present. SEAD-3 systems without a GIC are unaffected since
the DT fixup code generates interrupt specifiers that are valid for the
CPU interrupt controller.
Fix this by adding the GIC_SHARED & IRQ_TYPE_LEVEL_HIGH values to each
interrupt specifier.
Paul Burton [Fri, 2 Jun 2017 19:29:57 +0000 (12:29 -0700)]
MIPS: SEAD-3: Set interrupt-parent per-device, not at root node
The SEAD-3 board may be configured with or without a MIPS Global
Interrupt Controller (GIC). Because of this we have a device tree with a
default case of a GIC present, and code to fixup the device tree based
upon a configuration register that indicates the presence of the GIC.
In order to keep this DT fixup code simple, the interrupt-parent
property was specified at the root node of the SEAD-3 DT, allowing the
fixup code to simply change this property to the phandle of the CPU
interrupt controller if a GIC is not present & affect all
interrupt-using devices at once. This however causes a problem if we do
have a GIC & the device tree is used as-is, because the interrupt-parent
property of the root node applies to the CPU interrupt controller node.
This causes a cycle when of_irq_init() attempts to probe interrupt
controllers in order and boots fail due to a lack of configured
interrupts, with this message printed on the kernel console:
[ 0.000000] OF: of_irq_init: children remain, but no parents
Fix this by removing the interrupt-parent property from the DT root node
& instead setting it for each device which uses interrupts, ensuring
that the CPU interrupt controller node has no interrupt-parent &
allowing of_irq_init() to identify it as the root interrupt controller.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Reported-by: Keng Koh <keng.koh@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16187/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Fri, 2 Jun 2017 19:29:55 +0000 (12:29 -0700)]
MIPS: generic: Set RTC_ALWAYS_BCD to 0
Drivers for the mc146818 RTC generally check control registers to
determine whether a value is encoded as binary or as a binary coded
decimal. Setting RTC_ALWAYS_BCD to 1 effectively bypasses these checks
and causes drivers to always expect binary coded decimal values,
regardless of control register values.
This does not seem like a sane default - defaulting to 0 allows the
drivers to check control registers to determine encoding type & allows
the driver to work generically with both binary & BCD encodings. Set
this in mach-generic/mc146818rtc.h such that the generic kernel, or
platforms which don't provide a custom mc146818rtc.h, can have an RTC
driver which works with both encodings.
Paul Burton [Fri, 2 Jun 2017 19:29:54 +0000 (12:29 -0700)]
MIPS: generic: Abstract FDT fixup application
Introduce an apply_mips_fdt_fixups() function which can apply fixups to
an FDT based upon an array of fixup descriptions. This abstracts that
functionality such that legacy board code can apply FDT fixups without
requiring lots of duplication.
Paul Burton [Fri, 2 Jun 2017 19:29:53 +0000 (12:29 -0700)]
MIPS: generic/yamon-dt: Use serial* rather than uart* aliases
Name aliases in the SEAD-3 device tree serial0 & serial1, rather than
uart0 & uart1. This allows the core serial code to make use of the
aliases to ensure that the UARTs are consistently numbered as expected
rather than having the numbering depend upon probe order.
When translating YAMON-provided serial configuration to a device tree
stdout-path property adjust accordingly, such that we continue to
reference a valid alias.
Paul Burton [Fri, 2 Jun 2017 19:29:52 +0000 (12:29 -0700)]
MIPS: generic/yamon-dt: Support > 256MB of RAM
YAMON can expose more than 256MB of RAM to Linux on Malta by passing an
ememsize environment variable with the full size, but the kernel then
needs to be careful to choose the corresponding physical memory regions,
avoiding the IO memory window. This is platform dependent, and on Malta
it also depends on the memory layout which varies between system
controllers.
Extend yamon_dt_amend_memory() to generically handle this by taking
[e]memsize bytes of memory from an array of memory regions passed in as
a new parameter. Board code provides this array as appropriate depending
on its own memory map.
[paul.burton@imgtec.com: SEAD-3 supports 384MB DDR from 0]
Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16182/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Fri, 2 Jun 2017 19:29:51 +0000 (12:29 -0700)]
MIPS: generic/yamon-dt: Pull YAMON DT shim code out of SEAD-3 board
In preparation for supporting other YAMON-using boards (Malta) & sharing
code to translate information from YAMON into device tree properties,
pull the code doing so for the kernel command line, system memory &
serial configuration out of the SEAD-3 board code.
Paul Burton [Fri, 2 Jun 2017 19:29:58 +0000 (12:29 -0700)]
MIPS: SEAD-3: Remove GIC timer from DT
The SEAD-3 board doesn't & never has configured the GIC frequency.
Remove the timer node from the DT in order to avoid attempting to probe
the GIC clocksource/clockevent driver which will produce error messages
such as these during boot:
[ 0.000000] GIC frequency not specified.
[ 0.000000] Failed to initialize '/interrupt-controller@1b1c0000/timer': -22
[ 0.000000] clocksource_probe: no matching clocksources found
James Hogan [Wed, 31 May 2017 15:19:50 +0000 (16:19 +0100)]
MIPS: Branch straight to ll in mips_atomic_set()
Adjust the atomic loop in the MIPS_ATOMIC_SET operation of the sysmips
system call to branch straight back to the linked load rather than
jumping via a different subsection (whose purpose remains a mystery to
me).
James Hogan [Wed, 31 May 2017 15:19:49 +0000 (16:19 +0100)]
MIPS: Fix mips_atomic_set() with EVA
EVA linked loads (LLE) and conditional stores (SCE) should be used on
EVA kernels for the MIPS_ATOMIC_SET operation of the sysmips system
call, or else the atomic set will apply to the kernel view of the
virtual address space (potentially unmapped on EVA kernels) rather than
the user view (TLB mapped).
James Hogan [Wed, 31 May 2017 15:19:48 +0000 (16:19 +0100)]
MIPS: Save static registers before sysmips
The MIPS sysmips system call handler may return directly from the
MIPS_ATOMIC_SET case (mips_atomic_set()) to syscall_exit. This path
restores the static (callee saved) registers, however they won't have
been saved on entry to the system call.
Use the save_static_function() macro to create a __sys_sysmips wrapper
function which saves the static registers before calling sys_sysmips, so
that the correct static register state is restored by syscall_exit.
Fixes: f1e39a4a616c ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16149/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
James Hogan [Wed, 31 May 2017 15:19:47 +0000 (16:19 +0100)]
MIPS: Fix mips_atomic_set() retry condition
The inline asm retry check in the MIPS_ATOMIC_SET operation of the
sysmips system call has been backwards since commit f1e39a4a616c ("MIPS:
Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler")
merged in v2.6.32, resulting in the non R10000_LLSC_WAR case retrying
until the operation was inatomic, before returning the new value that
was probably just written multiple times instead of the old value.
Invert the branch condition to fix that particular issue.
Fixes: f1e39a4a616c ("MIPS: Rewrite sysmips(MIPS_ATOMIC_SET, ...) in C with inline assembler") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-mips@linux-mips.org Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16148/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a definition of the perf registers for the new I6500 core.
Since I6500 has the same event definitions as I6400, re-use the existing
i6400 map structures by renaming them to a slightly more generic
'i6x00_***_map'.
Paul Burton [Fri, 2 Jun 2017 19:39:04 +0000 (12:39 -0700)]
MIPS: Probe the I6500 CPU
Introduce the I6500 PRID & probe it just the same way as I6400. The MIPS
I6500 is the latest in Imagination Technologies' I-Class range of CPUs,
with a focus on scalability & heterogeneity. It introduces the notion of
multiple clusters to the MIPS Coherent Processing System, allowing for a
far higher total number of cores & threads in a system when compared
with its predecessors. Clusters don't need to be identical, and may
contain differing numbers of cores & IOCUs, or cores with differing
properties.
This patch alone adds the basic support for booting Linux on an I6500
CPU without support for any of its new functionality, for which support
will be introduced in further patches.
Paul Burton [Tue, 13 Jun 2017 17:01:08 +0000 (10:01 -0700)]
MIPS: Perform post-DMA cache flushes on systems with MAARs
Recent CPUs from Imagination Technologies such as the I6400 or P6600 are
able to speculatively fetch data from memory into caches. This means
that if used in a system with non-coherent DMA they require that caches
be invalidated after a device performs DMA, and before the CPU reads the
DMA'd data, in order to ensure that stale values weren't speculatively
prefetched.
Such CPUs also introduced Memory Accessibility Attribute Registers
(MAARs) in order to control the regions in which they are allowed to
speculate. Thus we can use the presence of MAARs as a good indication
that the CPU requires the above cache maintenance. Use the presence of
MAARs to determine the result of cpu_needs_post_dma_flush() in the
default case, in order to handle these recent CPUs correctly.
Note that the return type of cpu_needs_post_dma_flush() is changed to
bool, such that it's clearer what's happening when cpu_has_maar is cast
to bool for the return value. If this patch were backported to a
pre-v4.7 kernel then MIPS_CPU_MAAR was 1ull<<34, so when cast to an int
we would incorrectly return 0. It so happens that MIPS_CPU_MAAR is
currently 1ull<<30, so when truncated to an int gives a non-zero value
anyway, but even so the implicit conversion from long long int to bool
makes it clearer to understand what will happen than the implicit
conversion from long long int to int would. The bool return type also
fits this usage better semantically, so seems like an all-round win.
Thanks to Ed for spotting the issue for pre-v4.7 kernels & suggesting
the return type change.
David Daney [Tue, 13 Jun 2017 22:28:47 +0000 (15:28 -0700)]
MIPS: Give __secure_computing() access to syscall arguments.
KProbes of __seccomp_filter() are not very useful without access to
the syscall arguments.
Do what x86 does, and populate a struct seccomp_data to be passed to
__secure_computing(). This allows samples/bpf/tracex5 to extract a
sensible trace.
Signed-off-by: David Daney <david.daney@cavium.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16368/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
David Daney [Tue, 13 Jun 2017 22:28:43 +0000 (15:28 -0700)]
MIPS: Optimize uasm insn lookup.
Instead of doing a linear search through the insn_table for each
instruction, use the opcode as direct index into the table. This will
give constant time lookup performance as the number of supported
opcodes increases. Make the tables const as they are only ever read.
For uasm-mips.c sort the table alphabetically, and remove duplicate
entries, uasm-micromips.c was already sorted and duplicate free.
There is a small savings in object size as struct insn loses a field:
$ size arch/mips/mm/uasm-mips.o arch/mips/mm/uasm-mips.o.save
text data bss dec hex filename
10040 0 0 10040 2738 arch/mips/mm/uasm-mips.o
9240 1120 0 10360 2878 arch/mips/mm/uasm-mips.o.save
Signed-off-by: David Daney <david.daney@cavium.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Matt Redfearn <matt.redfearn@imgtec.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16365/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Paul Burton [Thu, 30 Mar 2017 18:37:45 +0000 (11:37 -0700)]
MIPS: module: Unify rel & rela reloc handling
The module load code has previously had entirely separate
implementations for rel & rela style relocs, which unnecessarily
duplicates a whole lot of code. Unify the implementations of both types
of reloc, sharing the bulk of the code.
Paul Burton [Thu, 30 Mar 2017 18:37:44 +0000 (11:37 -0700)]
MIPS: module: Ensure we always clean up r_mips_hi16_list
If we hit an error whilst processing a reloc then we would return early
from apply_relocate & potentially not free entries in r_mips_hi16_list,
thereby leaking memory. Fix this by ensuring that we always run the code
to free r_mipps_hi16_list when errors occur.
Signed-off-by: Paul Burton <paul.burton@imgtec.com> Fixes: 861667dc82f5 ("MIPS: Fix race condition in module relocation code.") Fixes: 04211a574641 ("MIPS: Bail on unsupported module relocs") Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15831/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Linus Torvalds [Sun, 25 Jun 2017 18:59:19 +0000 (11:59 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"A few fixes for timekeeping and timers:
- Plug a subtle race due to a missing READ_ONCE() in the timekeeping
code where reloading of a pointer results in an inconsistent
callback argument being supplied to the clocksource->read function.
- Correct the CLOCK_MONOTONIC_RAW sub-nanosecond accounting in the
time keeping core code, to prevent a possible discontuity.
- Apply a similar fix to the arm64 vdso clock_gettime()
implementation
- Add missing includes to clocksource drivers, which relied on
indirect includes which fails in certain configs.
- Use the proper iomem pointer for read/iounmap in a probe function"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW
time: Fix CLOCK_MONOTONIC_RAW sub-nanosecond accounting
time: Fix clock->read(clock) race around clocksource changes
clocksource: Explicitly include linux/clocksource.h when needed
clocksource/drivers/arm_arch_timer: Fix read and iounmap of incorrect variable
Linus Torvalds [Sun, 25 Jun 2017 18:55:21 +0000 (11:55 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
"Three fixlets for perf:
- Return the proper error code if aux buffers for a event are not
supported.
- Calculate the probe offset for inlined functions correctly
- Update the Skylake DTLB load/store miss event so it can count 1G
TLB entries as well"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Fix probe definition for inlined functions
perf/x86/intel: Add 1G DTLB load/store miss support for SKL
perf/aux: Correct return code of rb_alloc_aux() if !has_aux(ev)
Linus Torvalds [Sun, 25 Jun 2017 17:39:43 +0000 (10:39 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input fixes from Dmitry Torokhov:
- a quirk to i8042 to ignore timeout bit on Lifebook AH544
- a fixup to Synaptics RMI function 54 that was breaking some Dells
- a fix for memory leak in soc_button_array driver
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: synaptics-rmi4 - only read the F54 query registers which are used
Input: i8042 - add Fujitsu Lifebook AH544 to notimeout list
Input: soc_button_array - fix leaking the ACPI button descriptor buffer
Pull SCSI target fixes from Nicholas Bellinger:
"Here are the target-pending fixes for v4.12-rc7 that have been queued
up for the last 2 weeks. This includes:
- Fix a TMR related kref underflow detected by the recent refcount_t
conversion in upstream.
- Fix a iscsi-target corner case during explicit connection logout
timeout failure.
- Address last fallout in iscsi-target immediate data handling from
v4.4 target-core now allowing control CDB payload underflow"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
iscsi-target: Reject immediate data underflow larger than SCSI transfer length
iscsi-target: Fix delayed logout processing greater than SECONDS_FOR_LOGOUT_COMP
target: Fix kref->refcount underflow in transport_cmd_finish_abort
Linus Torvalds [Sat, 24 Jun 2017 23:18:00 +0000 (16:18 -0700)]
Merge tag 'kbuild-fixes-v4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
"Nothing scary, just some random fixes:
- fix warnings of host programs
- fix "make tags" when COMPILED_SOURCE=1 is specified along with O=
- clarify help message of C=1 option
- fix dependency for ncurses compatibility check
- fix "make headers_install" for fakechroot environment"
* tag 'kbuild-fixes-v4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: fix sparse warnings in nconfig
kbuild: fix header installation under fakechroot environment
kconfig: Check for libncurses before menuconfig
Kbuild: tiny correction on `make help`
tags: honor COMPILED_SOURCE with apart output directory
genksyms: add printf format attribute to error_with_pos()
Linus Torvalds [Sat, 24 Jun 2017 09:24:53 +0000 (02:24 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull timer fix from Eric Biederman:
"This fixes an issue of confusing injected signals with the signals
from posix timers that has existed since posix timers have been in the
kernel.
This patch is slightly simpler than my earlier version of this patch
as I discovered in testing that I had misspelled "#ifdef
CONFIG_POSIX_TIMERS". So I deleted that unnecessary test and made
setting of resched_timer uncondtional.
I have tested this and verified that without this patch there is a
nasty hang that is easy to trigger, and with this patch everything
works properly"
Thomas Gleixner dixit:
"It fixes the problem at hand and covers the ptrace case as well, which
I missed.
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
signal: Only reschedule timers on signals timers have sent
Thomas Gleixner [Fri, 23 Jun 2017 08:50:38 +0000 (10:50 +0200)]
x86/mshyperv: Remove excess #includes from mshyperv.h
A recent commit included linux/slab.h in linux/irq.h. This breaks the build
of vdso32 on a 64-bit kernel.
The reason is that linux/irq.h gets included into the vdso code via
linux/interrupt.h which is included from asm/mshyperv.h. That makes the
32-bit vdso compile fail, because slab.h includes the pgtable headers for
64-bit on a 64-bit build.
Neither linux/clocksource.h nor linux/interrupt.h are needed in the
mshyperv.h header file itself - it has a dependency on <linux/atomic.h>.
Remove the includes and unbreak the build.
Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Fixes: dee863b571b0 ("hv: export current Hyper-V clocksource") Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1706231038460.2647@nanos Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Sat, 24 Jun 2017 00:53:16 +0000 (17:53 -0700)]
Merge tag 'powerpc-4.12-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some more powerpc fixes for 4.12. Most of these actually came in last
week but got held up for some more testing.
- three fixes for kprobes/ftrace/livepatch interactions.
- properly handle data breakpoints when using the Radix MMU.
- fix for perf sampling of registers during call_usermodehelper().
- properly initialise the thread_info on our emergency stacks
- add an explicit flush when doing TLB invalidations for a process
using NPU2.
Thanks to: Alistair Popple, Naveen N. Rao, Nicholas Piggin, Ravi
Bangoria, Masami Hiramatsu"
* tag 'powerpc-4.12-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64: Initialise thread_info for emergency stacks
powerpc/powernv/npu-dma: Add explicit flush when sending an ATSD
powerpc/perf: Fix oops when kthread execs user process
powerpc/64s: Handle data breakpoints in Radix mode
powerpc/kprobes: Skip livepatch_handler() for jprobes
powerpc/ftrace: Pass the correct stack pointer for DYNAMIC_FTRACE_WITH_REGS
powerpc/kprobes: Pause function_graph tracing during jprobes handling
Linus Torvalds [Sat, 24 Jun 2017 00:49:12 +0000 (17:49 -0700)]
Merge tag 'acpi-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fix from Rafael Wysocki:
"This fixes the ACPI-based enumeration of some I2C and SPI devices
broken in 4.11.
Specifics:
- I2C and SPI devices are expected to be enumerated by the I2C and
SPI subsystems, respectively, but due to a change made during the
4.11 cycle, in some cases the ACPI core marks them as already
enumerated which causes the I2C and SPI subsystems to overlook
them, so fix that (Jarkko Nikula)"
* tag 'acpi-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / scan: Fix enumeration for special SPI and I2C devices
Linus Torvalds [Sat, 24 Jun 2017 00:40:41 +0000 (17:40 -0700)]
Merge tag 'gpio-v4.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fix from Linus Walleij:
"A single GPIO patch fixing the compatible string for the MVEBU PWM
controller embedded in the GPIO controller before we release v4.12.
Hopefully"
* tag 'gpio-v4.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: mvebu: change compatible string for PWM support
Linus Torvalds [Sat, 24 Jun 2017 00:37:56 +0000 (17:37 -0700)]
Merge tag 'sound-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Nothing exciting here, just a few stable fixes:
- suppress spurious kernel WARNING in PCM core
- fix potential spin deadlock at error handling in firewire
- HD-audio PCI ID addition / fixup"
* tag 'sound-4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Apply quirks to Broxton-T, too
ALSA: firewire-lib: Fix stall of process context at packet error
ALSA: pcm: Don't treat NULL chmap as a fatal error
ALSA: hda - Add Coffelake PCI ID
Linus Torvalds [Sat, 24 Jun 2017 00:35:57 +0000 (17:35 -0700)]
Merge tag 'drm-fixes-for-v4.12-rc7' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"A varied bunch of fixes, one for an API regression with connectors.
Otherwise amdgpu and i915 have a bunch of varied fixes, the shrinker
ones being the most important"
* tag 'drm-fixes-for-v4.12-rc7' of git://people.freedesktop.org/~airlied/linux:
drm: Fix GETCONNECTOR regression
drm/radeon: add a quirk for Toshiba Satellite L20-183
drm/radeon: add a PX quirk for another K53TK variant
drm/amdgpu: adjust default display clock
drm/amdgpu/atom: fix ps allocation size for EnableDispPowerGating
drm/amdgpu: add Polaris12 DID
drm/i915: Don't enable backlight at setup time.
drm/i915: Plumb the correct acquire ctx into intel_crtc_disable_noatomic()
drm/i915: Fix deadlock witha the pipe A quirk during resume
drm/i915: Remove __GFP_NORETRY from our buffer allocator
drm/i915: Encourage our shrinker more when our shmemfs allocations fails
drm/i915: Differentiate between sw write location into ring and last hw read
Linus Torvalds [Sat, 24 Jun 2017 00:32:05 +0000 (17:32 -0700)]
Merge tag 'for-4.12/dm-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- a revert of a DM mirror commit that has proven to make the code prone
to crash
- a DM io reference count fix that resolves a NULL pointer seen when
issuing discards to a DM mirror target's device whose mirror legs do
not all support discards
- a couple DM integrity fixes
* tag 'for-4.12/dm-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm io: fix duplicate bio completion due to missing ref count
dm integrity: fix to not disable/enable interrupts from interrupt context
Revert "dm mirror: use all available legs on multiple failures"
dm integrity: reject mappings too large for device
Linus Torvalds [Fri, 23 Jun 2017 23:30:52 +0000 (16:30 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"8 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
fs/exec.c: account for argv/envp pointers
ocfs2: fix deadlock caused by recursive locking in xattr
slub: make sysfs file removal asynchronous
lib/cmdline.c: fix get_options() overflow while parsing ranges
fs/dax.c: fix inefficiency in dax_writeback_mapping_range()
autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL
mm/vmalloc.c: huge-vmap: fail gracefully on unexpected huge vmap mappings
mm, thp: remove cond_resched from __collapse_huge_page_copy
Kees Cook [Fri, 23 Jun 2017 22:08:57 +0000 (15:08 -0700)]
fs/exec.c: account for argv/envp pointers
When limiting the argv/envp strings during exec to 1/4 of the stack limit,
the storage of the pointers to the strings was not included. This means
that an exec with huge numbers of tiny strings could eat 1/4 of the stack
limit in strings and then additional space would be later used by the
pointers to the strings.
For example, on 32-bit with a 8MB stack rlimit, an exec with 1677721
single-byte strings would consume less than 2MB of stack, the max (8MB /
4) amount allowed, but the pointers to the strings would consume the
remaining additional stack space (1677721 * 4 == 6710884).
The result (1677721 + 6710884 == 8388605) would exhaust stack space
entirely. Controlling this stack exhaustion could result in
pathological behavior in setuid binaries (CVE-2017-1000365).
[akpm@linux-foundation.org: additional commenting from Kees] Fixes: b6a2fea39318 ("mm: variable length argument support") Link: http://lkml.kernel.org/r/20170622001720.GA32173@beast Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Qualys Security Advisory <qsa@qualys.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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