Just like for INVALL, GICv4.1 has grown a VPE-aware INVLPI register.
Let's plumb it in and make use of the DirectLPI code in that case.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-16-maz@kernel.org
Since GICv4.1 gives us a per-VPE doorbell, avoid programming anything
else on VMOVI/VMAPI/VMAPTI and on any other action that would have
otherwise resulted in a per-VLPI doorbell to be programmed.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-15-maz@kernel.org
GICv4.1 redistributors have a VPE-aware INVALL register. Progress!
We can now emulate a guest-requested INVALL without emiting a
VINVALL command.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-14-maz@kernel.org
When descheduling a VPE, special care must be taken to tell the GIC
about whether we want to receive a doorbell or not. This is a
major improvement on GICv4.0, where the doorbell had to be separately
enabled/disabled.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-13-maz@kernel.org
Making a VPE resident on GICv4.1 is pretty simple, as it is just a
single write to the local redistributor. We just need extra information
about which groups to enable, which the KVM code will have to provide.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-12-maz@kernel.org
masking/unmasking doorbells on GICv4.1 relies on a new INVDB command,
which broadcasts the invalidation to all RDs.
Implement the new command as well as the masking callbacks, and plug
the whole thing into the v4.1 VPE irqchip.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-11-maz@kernel.org
Just like for GICv4.0, each VPE has its own doorbell interrupt, and
thus an irqchip that manages them. Since the doorbell management is
quite different on GICv4.1, let's introduce an almost empty irqchip
the will get populated over the next new patches.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-10-maz@kernel.org
With GICv4.1, VMOVP is extended to allow a default doorbell to be
specified, as well as a validity bit for this doorbell. As an added
bonus, VMOVP isn't required anymore of moving a VPE between
redistributors that share the same affinity.
Let's add this support to the VMOVP builder, and make sure we don't
issue the command if we don't really need to.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-9-maz@kernel.org
The infamous VPE proxy device isn't used with GICv4.1 because:
- we can invalidate any LPI from the DirectLPI MMIO interface
- the ITS and redistributors understand the life cycle of
the doorbell, so we don't need to enable/disable it all
the time
So let's escape early from the proxy related functions.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-8-maz@kernel.org
The ITS VMAPP command gains some new fields with GICv4.1:
- a default doorbell, which allows a single doorbell to be used for
all the VLPIs routed to a given VPE
- a pointer to the configuration table (instead of having it in a register
that gets context switched)
- a flag indicating whether this is the first map or the last unmap for
this particular VPE
- a flag indicating whether the pending table is known to be zeroed, or not
Plumb in the new fields in the VMAPP builder, and add the map/unmap
refcounting so that the ITS can do the right thing.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-7-maz@kernel.org
GICv4.1 defines a new VPE table that is potentially shared between
both the ITSs and the redistributors, following complicated affinity
rules.
To make things more confusing, the programming of this table at
the redistributor level is reusing the GICv4.0 GICR_VPROPBASER register
for something completely different.
The code flow is somewhat complexified by the need to respect the
affinities required by the HW, meaning that tables can either be
inherited from a previously discovered ITS or redistributor.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-6-maz@kernel.org
While GICv4.0 mandates 16 bit worth of VPEIDs, GICv4.1 allows smaller
implementations to be built. Add the required glue to dynamically
compute the limit.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-3-maz@kernel.org
GICv4.1 supports the RVPEID ("Residency per vPE ID"), which allows for
a much efficient way of making virtual CPUs resident (to allow direct
injection of interrupts).
The functionnality needs to be discovered on each and every redistributor
in the system, and disabled if the settings are inconsistent.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191224111055.11836-2-maz@kernel.org
When updating an LPI configuration, get_vlpi_map() may be passed a
irq_data structure relative to an ITS domain (the normal case) or one
that is relative to the core GICv3 domain in the case of a GICv4
doorbell.
In the latter case, special care must be take not to dereference
the irq_chip data as an its_dev structure, as that isn't what is
stored there. Instead, check *first* whether the IRQ is forwarded
to a vcpu, and only then try to obtain the vlpi mapping.
Fixes: c1d4d5cd20 ("irqchip/gic-v3-its: Add its_vlpi_map helpers")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20200122085609.658-1-yuzenghui@huawei.com
Since commit 43e23b6c0b ("debugfs: log errors when something goes wrong")
debugfs logs attempts to create existing files.
However binder attempts to create multiple debugfs files with
the same name when a single PID has multiple contexts, this leads
to log spamming during an Android boot (17 such messages during
boot on my system).
Fix this by checking if we already know the PID and only create
the debugfs entry for the first context per PID.
Do the same thing for binderfs for symmetry.
Signed-off-by: Martin Fuzzey <martin.fuzzey@flowbird.group>
Acked-by: Todd Kjos <tkjos@google.com>
Fixes: 43e23b6c0b ("debugfs: log errors when something goes wrong")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1578671054-5982-1-git-send-email-martin.fuzzey@flowbird.group
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously, the assignment to the local variable 'now' took place
before the for loop. The loop is unconditional so it will be entered
at least once. The variable 'now' is reassigned in the loop and is not
used before reassigning. Therefore, the assignment before the loop is
unnecessary and can be removed.
No code changed:
# arch/x86/kernel/tsc_sync.o:
text data bss dec hex filename
3569 198 44 3811 ee3 tsc_sync.o.before
3569 198 44 3811 ee3 tsc_sync.o.after
md5:
36216de29b208edbcd34fed9fe7f7b69 tsc_sync.o.before.asm
36216de29b208edbcd34fed9fe7f7b69 tsc_sync.o.after.asm
[ bp: Massage commit message. ]
Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200118171143.25178-1-mateusznosek0@gmail.com
Commit 99c9a923e9 ("tracing/uprobe: Fix double perf_event
linking on multiprobe uprobe") moved trace_uprobe_filter on
trace_probe_event. However, since it introduced a flexible
data structure with char array and type casting, the
alignment of trace_uprobe_filter can be broken.
This changes the type of the array to trace_uprobe_filter
data strucure to fix it.
Link: http://lore.kernel.org/r/20200120124022.GA14897@hirez.programming.kicks-ass.net
Link: http://lkml.kernel.org/r/157966340499.5107.10978352478952144902.stgit@devnote2
Fixes: 99c9a923e9 ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This limitation are never lunched from introduce commit 970988e19e
("tracing/kprobe: Add kprobe_event= boot parameter")
Could we remove it if no intention to implement it?
Link: http://lkml.kernel.org/r/1579586075-45132-1-git-send-email-alex.shi@linux.alibaba.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Setting a kprobe on getname_flags() failed:
$ echo 'p:tmr1 getname_flags +0(%r2):ustring' > kprobe_events
-bash: echo: write error: Invalid argument
Debugging the kprobes code showed that the address of
getname_flags() is contained in the __bug_table. Kprobes
doesn't allow to set probes at BUG() locations.
$ objdump -j __bug_table -x build/fs/namei.o
[..]
0000000000000108 R_390_PC32 .text+0x00000000000075a8
000000000000010c R_390_PC32 .L223+0x0000000000000004
I was expecting getname_flags() to start with a BUG(), but:
7598: e3 20 10 00 00 04 lg %r2,0(%r1)
759e: c0 f4 00 00 00 00 jg 759e <putname+0x7e>
75a0: R_390_PLT32DBL kmem_cache_free+0x2
75a4: a7 f4 00 01 j 75a6 <putname+0x86>
00000000000075a8 <getname_flags>:
75a8: c0 04 00 00 00 00 brcl 0,75a8 <getname_flags>
75ae: eb 6f f0 48 00 24 stmg %r6,%r15,72(%r15)
75b4: b9 04 00 ef lgr %r14,%r15
75b8: e3 f0 ff a8 ff 71 lay %r15,-88(%r15)
So the BUG() is actually the last opcode of the previous function.
Fix this by switching to using the MONITOR CALL (MC) instruction,
and set the entry in __bug_table to the beginning of that MC.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Currently backtrace from ftraced function does not contain ftraced
function itself. e.g. for "path_openat":
arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15e/0x3d8
ftrace_graph_caller+0x0/0x1c <-- ftrace code
do_filp_open+0x7c/0xe8 <-- ftraced function caller
do_open_execat+0x76/0x1b8
open_exec+0x52/0x78
load_elf_binary+0x180/0x1160
search_binary_handler+0x8e/0x288
load_script+0x2a8/0x2b8
search_binary_handler+0x8e/0x288
__do_execve_file.isra.39+0x6fa/0xb40
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8
Ftraced function is expected in the backtrace by ftrace kselftests, which
are now failing. It would also be nice to have it for clarity reasons.
"ftrace_caller" itself is called without stack frame allocated for it
and does not store its caller (ftraced function). Instead it simply
allocates a stack frame for "ftrace_trace_function" and sets backchain
to point to ftraced function stack frame (which contains ftraced function
caller in saved r14).
To fix this issue make "ftrace_caller" allocate a stack frame
for itself just to store ftraced function for the stack unwinder.
As a result backtrace looks like the following:
arch_stack_walk+0x15c/0x2d8
stack_trace_save+0x50/0x68
stack_trace_call+0x15e/0x3d8
ftrace_graph_caller+0x0/0x1c <-- ftrace code
path_openat+0x6/0xd60 <-- ftraced function
do_filp_open+0x7c/0xe8 <-- ftraced function caller
do_open_execat+0x76/0x1b8
open_exec+0x52/0x78
load_elf_binary+0x180/0x1160
search_binary_handler+0x8e/0x288
load_script+0x2a8/0x2b8
search_binary_handler+0x8e/0x288
__do_execve_file.isra.39+0x6fa/0xb40
__s390x_sys_execve+0x56/0x68
system_call+0xdc/0x2d8
Reported-by: Sven Schnelle <sven.schnelle@ibm.com>
Tested-by: Sven Schnelle <sven.schnelle@ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
clang 10 introduces -mpacked-stack compiler option implementation. At the
same time currently it does not support a combination of -mpacked-stack
and -mbackchain. This leads to the following build error:
clang: error: unsupported option '-mpacked-stack with -mbackchain' for
target 's390x-ibm-linux'
If/when clang adds support for a combination of -mpacked-stack and
-mbackchain it would also require -msoft-float (like gcc does). According
to Ulrich Weigand "stack slot assigned to the kernel backchain overlaps
the stack slot assigned to the FPR varargs (both are required to be
placed immediately after the saved r15 slot if present)."
Extend -mpacked-stack compiler option support check to include all 3
options -mpacked-stack -mbackchain -msoft-float which must present to
support -mpacked-stack with -mbackchain.
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Currently kernel build fails under clang if jump labels are enabled.
The problem is "X" constraint usage "Any operand whatsoever is allowed",
for which clang produces the following:
.pushsection __jump_table,"aw"
.balign 8
.long 0b-.,.Ltmp577-.
.quad %r0+0-. # %r0 is not allowed here
.popsection
Under gcc constraints "X" or "jdd" (gcc > 9) are used for static keys.
Ideally, we'd have used "i" for gcc, but it doesn't work in all cases
with -fPIC code. This is gcc-specific problem that doesn't exist in llvm.
Since clang does not have "jdd" simply always use "i" constraint for it.
Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use macro DIV_ROUND_UP() for calculation of number of SDBT
SDBT pages required for index pages. This macro is already
used throughout the file.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use kzalloc() to allocate auxiliary buffer structure initialized
with all zeroes to avoid random value in trace output.
Avoid double access to SBD hardware flags.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Convert debug traces to print the head/alert/empty marks
consistently as decimal numbers. Add some trace statements
to enable easier debugging during auxiliary tracing.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
When we try to recover a PCI function using
echo 1 > /sys/bus/pci/devices/<id>/recover
or manually with
echo 1 > /sys/bus/pci/devices/<id>/remove
echo 0 > /sys/bus/pci/slots/<slot>/power
echo 1 > /sys/bus/pci/slots/<slot>/power
clp_disable_fn() / clp_enable_fn() call clp_set_pci_fn() to first
disable and then reenable the function.
When the function is already in the requested state we may be left with
an invalid function handle.
To get a new valid handle we do a clp_list_pci() call. For this we need
both the function ID and function handle in clp_set_pci_fn() so pass the
zdev and get both.
To simplify things also pull setting the refreshed function handle into
clp_set_pci_fn()
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
If we exit due to a bad input to trace_printk() (highly unlikely), then the
buffer variable will not be initialized when we unnest the ring buffer.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add TEST opcode to Group3-2 reg=001b as same as Group3-1 does.
Commit
12a78d43de ("x86/decoder: Add new TEST instruction pattern")
added a TEST opcode assignment to f6 XX/001/XXX (Group 3-1), but did
not add f7 XX/001/XXX (Group 3-2).
Actually, this TEST opcode variant (ModRM.reg /1) is not described in
the Intel SDM Vol2 but in AMD64 Architecture Programmer's Manual Vol.3,
Appendix A.2 Table A-6. ModRM.reg Extensions for the Primary Opcode Map.
Without this fix, Randy found a warning by insn_decoder_test related
to this issue as below.
HOSTCC arch/x86/tools/insn_decoder_test
HOSTCC arch/x86/tools/insn_sanity
TEST posttest
arch/x86/tools/insn_decoder_test: warning: Found an x86 instruction decoder bug, please report this.
arch/x86/tools/insn_decoder_test: warning: ffffffff81000bf1: f7 0b 00 01 08 00 testl $0x80100,(%rbx)
arch/x86/tools/insn_decoder_test: warning: objdump says 6 bytes, but insn_get_length() says 2
arch/x86/tools/insn_decoder_test: warning: Decoded and checked 11913894 instructions with 1 failures
TEST posttest
arch/x86/tools/insn_sanity: Success: decoded and checked 1000000 random instructions with 0 errors (seed:0x871ce29c)
To fix this error, add the TEST opcode according to AMD64 APM Vol.3.
[ bp: Massage commit message. ]
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lkml.kernel.org/r/157966631413.9580.10311036595431878351.stgit@devnote2
Restore the 'if (env->cur_state)' check that was incorrectly removed during
code move. Under memory pressure env->cur_state can be freed and zeroed inside
do_check(). Hence the check is necessary.
Fixes: 51c39bb1d5 ("bpf: Introduce function-by-function verification")
Reported-by: syzbot+b296579ba5015704d9fa@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200122024138.3385590-1-ast@kernel.org
I will lose access to my @arm.com email address next week, so
let's update the MAINTAINERS file and map it correctly in
.mailmap
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Though the second half of trampoline page is unused a task could be
preempted in the middle of the first half of trampoline and two
updates to trampoline would change the code from underneath the
preempted task. Hence wait for tasks to voluntarily schedule or go
to userspace. Add similar wait before freeing the trampoline.
Fixes: fec56f5890 ("bpf: Introduce BPF trampoline")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/bpf/20200121032231.3292185-1-ast@kernel.org
When seeding KALSR on a system where we have architecture level random
number generation make use of that entropy, mixing it in with the seed
passed by the bootloader. Since this is run very early in init before
feature detection is complete we open code rather than use archrandom.h.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Expose the ID_AA64ISAR0.RNDR field to userspace, as the RNG system
registers are always available at EL0.
Implement arch_get_random_seed_long using RNDR. Given that the
TRNG is likely to be a shared resource between cores, and VMs,
do not explicitly force re-seeding with RNDRRS. In order to avoid
code complexity and potential issues with hetrogenous systems only
provide values after cpufeature has finalized the system capabilities.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[Modified to only function after cpufeature has finalized the system
capabilities and move all the code into the header -- broonie]
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
[will: Advertise HWCAP via /proc/cpuinfo]
Signed-off-by: Will Deacon <will@kernel.org>
A load on an ESB page returning all 1's means that the underlying
device has invalidated the access to the PQ state of the interrupt
through mmio. It may happen, for example when querying a PHB interrupt
while the PHB is in an error state.
In that case, we should consider the interrupt to be invalid when
checking its state in the irq_get_irqchip_state() handler.
Fixes: da15c03b04 ("powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
[clg: wrote a commit log, introduced XIVE_ESB_INVALID ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200113130118.27969-1-clg@kaod.org
Let PPC_UV depend only on DEVICE_PRIVATE which in turn
will satisfy all the other required dependencies
Fixes: 013a53f2d2 ("powerpc: Ultravisor: Add PPC_UV config option")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200109092047.24043-1-bharata@linux.ibm.com
According to termbits.h SPARC supports few more baud rates
than currently defined in tty_baudrate.c.
Append supported ones to baud_table[] and baud_bits[].
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200115224124.74684-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Synchronize baud rate tables baud_table and baud_bits with each other
for better readability. This makes clear what is being used for SPARC.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200115224124.74684-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The main irq handler function starts by first masking disabled
interrupts in the status register values to ensure to only handle
enabled interrupts. This is important as when the RX path in the
hardware is disabled reading the RX fifo results in an external abort.
This checking must be done under the port lock, otherwise the following
can happen:
CPU1 | CPU2
|
irq triggers as there are chars |
in the RX fifo |
| grab port lock
imx_uart_int finds RRDY enabled |
and calls imx_uart_rxint which |
has to wait for port lock |
| disable RX (e.g. because we're
| using RS485 with !RX_DURING_TX)
|
| release port lock
read from RX fifo with RX |
disabled => exception |
So take the port lock only once in imx_uart_int() instead of in the
functions called from there.
Reported-by: Andre Renaud <arenaud@designa-electronics.com>
Cc: stable@vger.kernel.org
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20200121071702.20150-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Document the driver private data of the BCM2835 auxiliary UART so that
upcoming commits may add further members with proper kerneldoc.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/aea363c27fd541dba96d2ebfeee4f596c6d34932.1579175223.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On probe the bcm2835aux UART driver misreports the register base address
as 0x0:
ttyS0 at MMIO 0x0 (irq = 53, base_baud = 50000000) is a 16550
That's because the driver remaps the registers itself. Take advantage
of the generic remapping code in serial8250_request_std_resource() to
get a message with the correct address and to simplify the driver.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/7d1a9bdb05090d8e465fd15cd26d6e81538d07f9.1579175223.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The bcm2835aux UART driver stores a struct uart_8250_port in its private
data even though it's only passed once to serial8250_register_8250_port()
(which copies all relevant data) and becomes obsolete afterwards.
Allocate the struct on the stack instead for simplicity and to conserve
memory.
The driver also initializes a spinlock in the struct which is never used.
Drop that as well.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Martin Sperl <kernel@martin.sperl.org>
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/421d3aed4c34cc8447ac9c26c320961f1b787f11.1579175223.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
