This is a note to let you know that I've just added the patch titled
serial: pl011: Fix DMA ->flush_buffer()
to my tty git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git
in the tty-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From f6a196477184b99a31d16366a8e826558aa11f6d Mon Sep 17 00:00:00 2001
From: Vincent Whitchurch <vincent.whitchurch(a)axis.com>
Date: Mon, 18 Nov 2019 10:25:47 +0100
Subject: serial: pl011: Fix DMA ->flush_buffer()
PL011's ->flush_buffer() implementation releases and reacquires the port
lock. Due to a race condition here, data can end up being added to the
circular buffer but neither being discarded nor being sent out. This
leads to, for example, tcdrain(2) waiting indefinitely.
Process A Process B
uart_flush_buffer()
- acquire lock
- circ_clear
- pl011_flush_buffer()
-- release lock
-- dmaengine_terminate_all()
uart_write()
- acquire lock
- add chars to circ buffer
- start_tx()
-- start DMA
- release lock
-- acquire lock
-- turn off DMA
-- release lock
// Data in circ buffer but DMA is off
According to the comment in the code, the releasing of the lock around
dmaengine_terminate_all() is to avoid a deadlock with the DMA engine
callback. However, since the time this code was written, the DMA engine
API documentation seems to have been clarified to say that
dmaengine_terminate_all() (in the identically implemented but
differently named dmaengine_terminate_async() variant) does not wait for
any running complete callback to be completed and can even be called
from a complete callback. So there is no possibility of deadlock if the
DMA engine driver implements this API correctly.
So we should be able to just remove this release and reacquire of the
lock to prevent the aforementioned race condition.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch(a)axis.com>
Cc: stable <stable(a)vger.kernel.org>
Link: https://lore.kernel.org/r/20191118092547.32135-1-vincent.whitchurch@axis.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/tty/serial/amba-pl011.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 38e2d25f7e23..4b28134d596a 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -813,10 +813,8 @@ __acquires(&uap->port.lock)
if (!uap->using_tx_dma)
return;
- /* Avoid deadlock with the DMA engine callback */
- spin_unlock(&uap->port.lock);
- dmaengine_terminate_all(uap->dmatx.chan);
- spin_lock(&uap->port.lock);
+ dmaengine_terminate_async(uap->dmatx.chan);
+
if (uap->dmatx.queued) {
dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1,
DMA_TO_DEVICE);
--
2.24.0
"Shared MSRs" are guest MSRs that are written to the host MSRs but
keep their value until the next return to userspace. They support
a mask, so that some bits keep the host value, but this mask is
only used to skip an unnecessary MSR write and the value written
to the MSR is always the guest MSR.
Fix this and, while at it, do not update smsr->values[slot].curr if
for whatever reason the wrmsr fails. This should only happen due to
reserved bits, so the value written to smsr->values[slot].curr
will not match when the user-return notifier and the host value will
always be restored. However, it is untidy and in rare cases this
can actually avoid spurious WRMSRs on return to userspace.
Cc: stable(a)vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com>
---
arch/x86/kvm/x86.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6ea735d632e9..02863998af91 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -300,13 +300,14 @@ int kvm_set_shared_msr(unsigned slot, u64 value, u64 mask)
struct kvm_shared_msrs *smsr = per_cpu_ptr(shared_msrs, cpu);
int err;
- if (((value ^ smsr->values[slot].curr) & mask) == 0)
+ value = (value & mask) | (smsr->values[slot].host & ~mask);
+ if (value == smsr->values[slot].curr)
return 0;
- smsr->values[slot].curr = value;
err = wrmsrl_safe(shared_msrs_global.msrs[slot], value);
if (err)
return 1;
+ smsr->values[slot].curr = value;
if (!smsr->registered) {
smsr->urn.on_user_return = kvm_on_user_return;
user_return_notifier_register(&smsr->urn);
--
1.8.3.1
Hello,
We ran automated tests on a recent commit from this kernel tree:
Kernel repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
Commit: 6d539b8f097b - Linux 5.3.12-rc1
The results of these automated tests are provided below.
Overall result: FAILED (see details below)
Merge: OK
Compile: OK
Tests: FAILED
All kernel binaries, config files, and logs are available for download here:
https://artifacts.cki-project.org/pipelines/295147
One or more kernel tests failed:
x86_64:
❌ LTP lite
We hope that these logs can help you find the problem quickly. For the full
detail on our testing procedures, please scroll to the bottom of this message.
Please reply to this email if you have any questions about the tests that we
ran or if you have any suggestions on how to make future tests more effective.
,-. ,-.
( C ) ( K ) Continuous
`-',-.`-' Kernel
( I ) Integration
`-'
______________________________________________________________________________
Compile testing
---------------
We compiled the kernel for 3 architectures:
aarch64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
ppc64le:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
x86_64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
Hardware testing
----------------
We booted each kernel and ran the following tests:
aarch64:
Host 1:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Host 2:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ storage: SCSI VPD
✅ stress: stress-ng
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
ppc64le:
Host 1:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Host 2:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
x86_64:
Host 1:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
❌ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ pciutils: sanity smoke test
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ storage: SCSI VPD
✅ stress: stress-ng
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ❌ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
Host 2:
✅ Boot test
✅ Storage SAN device stress - mpt3sas driver
Host 3:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ IOMMU boot test
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Host 4:
✅ Boot test
🚧 ✅ IPMI driver test
🚧 ✅ IPMItool loop stress test
Host 5:
✅ Boot test
✅ Storage SAN device stress - megaraid_sas
Test sources: https://github.com/CKI-project/tests-beaker
💚 Pull requests are welcome for new tests or improvements to existing tests!
Waived tests
------------
If the test run included waived tests, they are marked with 🚧. Such tests are
executed but their results are not taken into account. Tests are waived when
their results are not reliable enough, e.g. when they're just introduced or are
being fixed.
Testing timeout
---------------
We aim to provide a report within reasonable timeframe. Tests that haven't
finished running are marked with ⏱. Reports for non-upstream kernels have
a Beaker recipe linked to next to each host.
Hello,
We ran automated tests on a recent commit from this kernel tree:
Kernel repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
Commit: 9ebab9194d83 - Linux 5.3.12-rc1
The results of these automated tests are provided below.
Overall result: FAILED (see details below)
Merge: OK
Compile: OK
Tests: FAILED
All kernel binaries, config files, and logs are available for download here:
https://artifacts.cki-project.org/pipelines/295031
One or more kernel tests failed:
ppc64le:
❌ xfstests: ext4
We hope that these logs can help you find the problem quickly. For the full
detail on our testing procedures, please scroll to the bottom of this message.
Please reply to this email if you have any questions about the tests that we
ran or if you have any suggestions on how to make future tests more effective.
,-. ,-.
( C ) ( K ) Continuous
`-',-.`-' Kernel
( I ) Integration
`-'
______________________________________________________________________________
Compile testing
---------------
We compiled the kernel for 3 architectures:
aarch64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
ppc64le:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
x86_64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
Hardware testing
----------------
We booted each kernel and ran the following tests:
aarch64:
Host 1:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Host 2:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ storage: SCSI VPD
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
ppc64le:
Host 1:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
Host 2:
✅ Boot test
❌ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
x86_64:
Host 1:
✅ Boot test
🚧 ✅ IPMI driver test
🚧 ✅ IPMItool loop stress test
Host 2:
✅ Boot test
✅ Storage SAN device stress - mpt3sas driver
Host 3:
✅ Boot test
✅ Storage SAN device stress - megaraid_sas
Host 4:
⚡ Internal infrastructure issues prevented one or more tests (marked
with ⚡⚡⚡) from running on this architecture.
This is not the fault of the kernel that was tested.
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ IOMMU boot test
🚧 ✅ selinux-policy: serge-testsuite
🚧 ⚡⚡⚡ Storage blktests
Host 5:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP lite
✅ Loopdev Sanity
✅ jvm test suite
✅ Memory function: memfd_create
✅ Memory function: kaslr
✅ AMTU (Abstract Machine Test Utility)
✅ LTP: openposix test suite
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ audit: audit testsuite test
✅ httpd: mod_ssl smoke sanity
✅ iotop: sanity
✅ tuned: tune-processes-through-perf
✅ pciutils: sanity smoke test
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ Usex - version 1.9-29
✅ storage: SCSI VPD
✅ stress: stress-ng
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ storage: dm/common
Test sources: https://github.com/CKI-project/tests-beaker
💚 Pull requests are welcome for new tests or improvements to existing tests!
Waived tests
------------
If the test run included waived tests, they are marked with 🚧. Such tests are
executed but their results are not taken into account. Tests are waived when
their results are not reliable enough, e.g. when they're just introduced or are
being fixed.
Testing timeout
---------------
We aim to provide a report within reasonable timeframe. Tests that haven't
finished running are marked with ⏱. Reports for non-upstream kernels have
a Beaker recipe linked to next to each host.