Pavel Tatashin says:
====================
sparc64: context wrap fixes
This patch series contains fixes for context wrap: when we are out of
context ids, and need to get a new version.
It fixes memory corruption issues which happen when more than number of
context ids (currently set to 8K) number of processes are started
simultaneously, and processes can get a wrong context.
sparc64: new context wrap:
- contains explanation of new wrap method, and also explanation of races
that it solves
sparc64: reset mm cpumask after wrap
- explains issue of not reseting cpu mask on a wrap
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The old method that is using xcall and softint to get new context id is
deleted, as it is replaced by a method of using per_cpu_secondary_mm
without xcall to perform the context wrap.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current wrap implementation has a race issue: it is called outside of
the ctx_alloc_lock, and also does not wait for all CPUs to complete the
wrap. This means that a thread can get a new context with a new version
and another thread might still be running with the same context. The
problem is especially severe on CPUs with shared TLBs, like sun4v. I used
the following test to very quickly reproduce the problem:
- start over 8K processes (must be more than context IDs)
- write and read values at a memory location in every process.
Very quickly memory corruptions start happening, and what we read back
does not equal what we wrote.
Several approaches were explored before settling on this one:
Approach 1:
Move smp_new_mmu_context_version() inside ctx_alloc_lock, and wait for
every process to complete the wrap. (Note: every CPU must WAIT before
leaving smp_new_mmu_context_version_client() until every one arrives).
This approach ends up with deadlocks, as some threads own locks which other
threads are waiting for, and they never receive softint until these threads
exit smp_new_mmu_context_version_client(). Since we do not allow the exit,
deadlock happens.
Approach 2:
Handle wrap right during mondo interrupt. Use etrap/rtrap to enter into
into C code, and issue new versions to every CPU.
This approach adds some overhead to runtime: in switch_mm() we must add
some checks to make sure that versions have not changed due to wrap while
we were loading the new secondary context. (could be protected by PSTATE_IE
but that degrades performance as on M7 and older CPUs as it takes 50 cycles
for each access). Also, we still need a global per-cpu array of MMs to know
where we need to load new contexts, otherwise we can change context to a
thread that is going way (if we received mondo between switch_mm() and
switch_to() time). Finally, there are some issues with window registers in
rtrap() when context IDs are changed during CPU mondo time.
The approach in this patch is the simplest and has almost no impact on
runtime. We use the array with mm's where last secondary contexts were
loaded onto CPUs and bump their versions to the new generation without
changing context IDs. If a new process comes in to get a context ID, it
will go through get_new_mmu_context() because of version mismatch. But the
running processes do not need to be interrupted. And wrap is quicker as we
do not need to xcall and wait for everyone to receive and complete wrap.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CTX_FIRST_VERSION defines the first context version, but also it defines
first context. This patch redefines it to only include the first context
version.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The only difference between these two functions is that in activate_mm we
unconditionally flush context. However, there is no need to keep this
difference after fixing a bug where cpumask was not reset on a wrap. So, in
this patch we combine these.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After a wrap (getting a new context version) a process must get a new
context id, which means that we would need to flush the context id from
the TLB before running for the first time with this ID on every CPU. But,
we use mm_cpumask to determine if this process has been running on this CPU
before, and this mask is not reset after a wrap. So, there are two possible
fixes for this issue:
1. Clear mm cpumask whenever mm gets a new context id
2. Unconditionally flush context every time process is running on a CPU
This patch implements the first solution
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hugetlb_bad_size needs to be called on invalid values. Also change the
pr_warn to a pr_err to better align with other platforms.
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
VIO devices were being looked up by their index in the machine
description node block, but this often varies over time as devices are
added and removed. Instead, store the ID and look up using the type,
config handle and ID.
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112541
Signed-off-by: David S. Miller <davem@davemloft.net>
When a TSB grows beyond its current capacity, a new TSB is allocated
and copy_tsb is called to copy entries from the old TSB to the new.
A hash shift based on page size is used to calculate the index of an
entry in the TSB. copy_tsb has hard coded PAGE_SHIFT in these
calculations. However, for huge page TSBs the value REAL_HPAGE_SHIFT
should be used. As a result, when copy_tsb is called for a huge page
TSB the entries are placed at the incorrect index in the newly
allocated TSB. When doing hardware table walk, the MMU does not
match these entries and we end up in the TSB miss handling code.
This code will then create and write an entry to the correct index
in the TSB. We take a performance hit for the table walk miss and
recreation of these entries.
Pass a new parameter to copy_tsb that is the page size shift to be
used when copying the TSB.
Suggested-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux SPARC64 limits NR_CPUS to 4064 because init_cpu_send_mondo_info()
only allocates a single page for NR_CPUS mondo entries. Thus we cannot
use all 4096 CPUs on some SPARC platforms.
To fix, allocate (2^order) pages where order is set according to the size
of cpu_list for possible cpus. Since cpu_list_pa and cpu_mondo_block_pa
are not used in asm code, there are no imm13 offsets from the base PA
that will break because they can only reach one page.
Orabug: 25505750
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Atish Patra <atish.patra@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit fb9a307d11 ("bpf: Allow CGROUP_SKB eBPF program to
access sk_buff") enabled programs of BPF_PROG_TYPE_CGROUP_SKB
type to use ld_abs/ind instructions. However, at this point,
we cannot use them, since offsets relative to SKF_LL_OFF will
end up pointing skb_mac_header(skb) out of bounds since in the
egress path it is not yet set at that point in time, but only
after __dev_queue_xmit() did a general reset on the mac header.
bpf_internal_load_pointer_neg_helper() will then end up reading
data from a wrong offset.
BPF_PROG_TYPE_CGROUP_SKB programs can use bpf_skb_load_bytes()
already to access packet data, which is also more flexible than
the insns carried over from cBPF.
Fixes: fb9a307d11 ("bpf: Allow CGROUP_SKB eBPF program to access sk_buff")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Chenbo Feng <fengc@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The check that queue is less or equal to zero is always true
because queue is a u32; queue is decremented and will wrap around
and never go -ve. Fix this by making queue an int.
Detected by CoverityScan, CID#1428988 ("Unsigned compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
stmmac_tso_allocator can fail to set the Last Descriptor bit
on a descriptor that actually was the last descriptor.
This happens when the buffer of the last descriptor ends
up having a size of exactly TSO_MAX_BUFF_SIZE.
When the IP eventually reaches the next last descriptor,
which actually has the bit set, the DMA will hang.
When the DMA hangs, we get a tx timeout, however,
since stmmac does not do a complete reset of the IP
in stmmac_tx_timeout, we end up in a state with
completely hung TX.
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Acked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Acked-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tun actually expects a symmetric hash for queue selecting to work
correctly, otherwise packets belongs to a single flow may be
redirected to the wrong queue. So this patch switch to use
__skb_get_hash_symmetric().
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ethoc_reset enables device interrupts, ethoc_interrupt may schedule a
NAPI poll before NAPI is enabled in the ethoc_open, which results in
device being unable to send or receive anything until it's closed and
reopened. In case the device is flooded with ingress packets it may be
unable to recover at all.
Move napi_enable above ethoc_reset in the ethoc_open to fix that.
Fixes: a170285772 ("net: Add support for the OpenCores 10/100 Mbps Ethernet MAC.")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently have the HSCTLR.A bit set, trapping unaligned accesses
at HYP, but we're not really prepared to deal with it.
Since the rest of the kernel is pretty happy about that, let's follow
its example and set HSCTLR.A to zero. Modern CPUs don't really care.
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
We currently have the SCTLR_EL2.A bit set, trapping unaligned accesses
at EL2, but we're not really prepared to deal with it. So far, this
has been unnoticed, until GCC 7 started emitting those (in particular
64bit writes on a 32bit boundary).
Since the rest of the kernel is pretty happy about that, let's follow
its example and set SCTLR_EL2.A to zero. Modern CPUs don't really
care.
Cc: stable@vger.kernel.org
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
__do_hyp_init has the rather bad habit of ignoring RES1 bits and
writing them back as zero. On a v8.0-8.2 CPU, this doesn't do anything
bad, but may end-up being pretty nasty on future revisions of the
architecture.
Let's preserve those bits so that we don't have to fix this later on.
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
We might call br_afspec() with p == NULL which is a valid use case if
the action is on the bridge device itself, but the bridge tunnel code
dereferences the p pointer without checking, so check if p is null
first.
Reported-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Fixes: efa5356b0d ("bridge: per vlan dst_metadata netlink support")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The register bits used for the frame mode were masked with DSA (0x1)
instead of the mask value (0x3) in the 6085 implementation of
port_set_frame_mode. Fix this.
Fixes: 56995cbc35 ("net: dsa: mv88e6xxx: Refactor CPU and DSA port setup")
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For both BT.656 and BT.1120 video, the pixel format
used by VPIF is Y/CbCr 4:2:2 in semi-planar format
(Luma in one plane and Chroma in another). This
corresponds to NV16 pixel format.
This is documented in section 36.2.3 of OMAP-L138
Technical Reference Manual, SPRUH77A.
The VPIF driver incorrectly sets the default format
to V4L2_PIX_FMT_YUV422P. Fix it.
Reported-by: Alejandro Hernandez <ajhernandez@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
The hardware codec is not colorspace aware. We should trust userspace to
set the correct colorimetry information on the OUTPUT queue and mirror
the exact same setting on the CAPTURE queue.
There is no reason to restrict colorspace to JPEG or REC709 only. Also,
set the default colorspace, as returned by calling VIDIOC_TRY/S_FMT with
V4L2_COLORSPACE_DEFAULT, initially.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
There is only one subdevice registered with the async framework so there
is no need for the driver to check which subdevice is bound or unbound.
Remove these checks since the async framework preforms this.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
[hans.verkuil@cisco.com: fix typo: surce -> source]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
