November 2024 - Linux-kselftest-mirror

[PATCH v4 0/4] Add support for the Idle HLT intercept feature

by Manali Shukla

The upcoming new Idle HLT Intercept feature allows for the HLT instruction execution by a vCPU to be intercepted by the hypervisor only if there are no pending V_INTR and V_NMI events for the vCPU. When the vCPU is expected to service the pending V_INTR and V_NMI events, the Idle HLT intercept won’t trigger. The feature allows the hypervisor to determine if the vCPU is actually idle and reduces wasteful VMEXITs. The idle HLT intercept feature is used for enlightened guests who wish to securely handle the events. When an enlightened guest does a HLT while an interrupt is pending, hypervisor will not have a way to figure out whether the guest needs to be re-entered or not. The Idle HLT intercept feature allows the HLT execution only if there are no pending V_INTR and V_NMI events. Presence of the Idle HLT Intercept feature is indicated via CPUID function Fn8000_000A_EDX[30]. Document for the Idle HLT intercept feature is available at [1]. This series is based on kvm-next/next (64dbb3a771a1) + [2]. Experiments done: ---------------- kvm_amd.avic is set to '0' for this experiment. The below numbers represent the average of 10 runs. Normal guest (L1) The below netperf command was run on the guest with smp = 1 (pinned). netperf -H <host ip> -t TCP_RR -l 60 ---------------------------------------------------------------- |with Idle HLT(transactions/Sec)|w/o Idle HLT(transactions/Sec)| ---------------------------------------------------------------- | 25645.7136 | 25773.2796 | ---------------------------------------------------------------- Number of transactions/sec with and without idle HLT intercept feature are almost same. Nested guest (L2) The below netperf command was run on L2 guest with smp = 1 (pinned). netperf -H <host ip> -t TCP_RR -l 60 ---------------------------------------------------------------- |with Idle HLT(transactions/Sec)|w/o Idle HLT(transactions/Sec)| ---------------------------------------------------------------- | 5655.4468 | 5755.2189 | ---------------------------------------------------------------- Number of transactions/sec with and without idle HLT intercept feature are almost same. Testing Done: - Tested the functionality for the Idle HLT intercept feature using selftest svm_idle_hlt_test. - Tested SEV and SEV-ES guest for the Idle HLT intercept functionality. - Tested the Idle HLT intercept functionality on nested guest. v3 -> v4 - Drop the patches to add vcpu_get_stat() into a new series [2]. - Added nested Idle HLT intercept support. v2 -> v3 - Incorporated Andrew's suggestion to structure vcpu_stat_types in a way that each architecture can share the generic types and also provide its own. v1 -> v2 - Done changes in svm_idle_hlt_test based on the review comments from Sean. - Added an enum based approach to get binary stats in vcpu_get_stat() which doesn't use string to get stat data based on the comments from Sean. - Added self_halt() and cli() helpers based on the comments from Sean. [1]: AMD64 Architecture Programmer's Manual Pub. 24593, April 2024, Vol 2, 15.9 Instruction Intercepts (Table 15-7: IDLE_HLT). https://bugzilla.kernel.org/attachment.cgi?id=306250 [2]: https://lore.kernel.org/kvm/20241021062226.108657-1-manali.shukla@amd.com/T… Manali Shukla (4): x86/cpufeatures: Add CPUID feature bit for Idle HLT intercept KVM: SVM: Add Idle HLT intercept support KVM: nSVM: implement the nested idle halt intercept KVM: selftests: KVM: SVM: Add Idle HLT intercept test arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/include/asm/svm.h | 1 + arch/x86/include/uapi/asm/svm.h | 2 + arch/x86/kvm/governed_features.h | 1 + arch/x86/kvm/svm/nested.c | 7 ++ arch/x86/kvm/svm/svm.c | 15 +++- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/x86_64/processor.h | 1 + .../selftests/kvm/x86_64/svm_idle_hlt_test.c | 89 +++++++++++++++++++ 9 files changed, 115 insertions(+), 3 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/svm_idle_hlt_test.c base-commit: c8d430db8eec7d4fd13a6bea27b7086a54eda6da prerequisite-patch-id: ca912571db5c004f77b70843b8dd35517ff1267f prerequisite-patch-id: 164ea3b4346f9e04bc69819278d20f5e1b5df5ed prerequisite-patch-id: 90d870f426ebc2cec43c0dd89b701ee998385455 prerequisite-patch-id: 45812b799c517a4521782a1fdbcda881237e1eda -- 2.34.1

1 day, 9 hours

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[PATCH 0/2] fix reading ESP during coredump

by Nam Cao

Hi, In /proc/PID/stat, there is the kstkesp field which is the stack pointer of a thread. While the thread is active, this field reads zero. But during a coredump, it should have a valid value. However, at the moment, kstkesp is zero even during coredump. The first commit fixes this problem, and the second commit adds a selftest to detect if this problem appears again in the future. Nam Cao (2): fs/proc: do_task_stat: Fix ESP not readable during coredump selftests: coredump: Add stackdump test fs/proc/array.c | 36 ++-- tools/testing/selftests/coredump/Makefile | 7 + tools/testing/selftests/coredump/README.rst | 50 ++++++ tools/testing/selftests/coredump/stackdump | 14 ++ .../selftests/coredump/stackdump_test.c | 154 ++++++++++++++++++ 5 files changed, 243 insertions(+), 18 deletions(-) create mode 100644 tools/testing/selftests/coredump/Makefile create mode 100644 tools/testing/selftests/coredump/README.rst create mode 100755 tools/testing/selftests/coredump/stackdump create mode 100644 tools/testing/selftests/coredump/stackdump_test.c -- 2.39.5

1 day, 23 hours

4
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[PATCH v1 0/4] KVM selftests enhancements

by Manali Shukla

This series was prompted by feedback given in [1]. Patch 1 : Adds safe_hlt() and cli() helpers. Patch 2, 3: Adds an interface to read vcpu stat in selftest. Adds a macro to generate compiler error to detect typos at compile time while parsing vcpu and vm stats. Patch 4 : Fix few of the selftests based on newly defined macro. This series was split from the Idle HLT intercept support series [2] because the series has a few changes in the vm_get_stat() interface as suggested in [1] and a few changes in two of the self-tests (nx_huge_pages_test.c and dirty_log_page_splitting_test.c) which use vm_get_stat() functionality to retrieve specified VM stats. These changes are unrelated to the Idle HLT intercept support series [2]. [1] https://lore.kernel.org/kvm/ZruDweYzQRRcJeTO@google.com/T/#m7cd7a110f0fcff9… [2] https://lore.kernel.org/kvm/ZruDweYzQRRcJeTO@google.com/T/#m6c67ca8ccb226e5… Manali Shukla (4): KVM: selftests: Add safe_halt() and cli() helpers to common code KVM: selftests: Add an interface to read the data of named vcpu stat KVM: selftests: convert vm_get_stat to macro KVM: selftests: Replace previously used vm_get_stat() to macro .../testing/selftests/kvm/include/kvm_util.h | 83 +++++++++++++++++-- .../kvm/include/x86_64/kvm_util_arch.h | 52 ++++++++++++ .../selftests/kvm/include/x86_64/processor.h | 17 ++++ tools/testing/selftests/kvm/lib/kvm_util.c | 40 +++++++++ .../x86_64/dirty_log_page_splitting_test.c | 6 +- .../selftests/kvm/x86_64/nx_huge_pages_test.c | 4 +- 6 files changed, 191 insertions(+), 11 deletions(-) base-commit: c8d430db8eec7d4fd13a6bea27b7086a54eda6da -- 2.34.1

4 days, 17 hours

2
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[PATCH v6 0/3] tracing: Support poll on event hist file

by Masami Hiramatsu (Google)

Hi, Here is the v6 patch to support polling on event 'hist' file. The previous version is here; https://lore.kernel.org/all/172398710447.295714.4489282566285719918.stgit@d… This version is rebased on the ftrace/for-next branch of the linux-trace tree, and use global irq_work and wq instead of per-event one. Background ---------- There has been interest in allowing user programs to monitor kernel events in real time. Ftrace provides `trace_pipe` interface to wait on events in the ring buffer, but it is needed to wait until filling up a page with events in the ring buffer. We can also peek the `trace` file periodically, but that is inefficient way to monitor a randomely happening event. Overview -------- This patch set allows user to `poll`(or `select`, `epoll`) on event histogram interface. As you know each event has its own `hist` file which shows histograms generated by trigger action. So user can set a new hist trigger on any event you want to monitor, and poll on the `hist` file until it is updated. There are 2 poll events are supported, POLLIN and POLLPRI. POLLIN means that there are any readable update on `hist` file and this event will be flashed only when you call read(). So, this is useful if you want to read the histogram periodically. The other POLLPRI event is for monitoring trace event. Like the POLLIN, this will be returned when the histogram is updated, but you don't need to read() the file and use poll() again. Note that this waits for histogram update (not event arrival), thus you must set a histogram on the event at first. Usage ----- Here is an example usage: ---- TRACEFS=/sys/kernel/tracing EVENT=$TRACEFS/events/sched/sched_process_free # setup histogram trigger and enable event echo "hist:key=comm" >> $EVENT/trigger echo 1 > $EVENT/enable # Wait for update poll pri $EVENT/hist # Event arrived. echo "process free event is comming" tail $TRACEFS/trace ---- The 'poll' command is in the selftest patch. You can take this series also from here; https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git/log/?h=t… Thank you, --- Masami Hiramatsu (Google) (3): tracing/hist: Add poll(POLLIN) support on hist file tracing/hist: Support POLLPRI event for poll on histogram selftests/tracing: Add hist poll() support test include/linux/trace_events.h | 14 +++ kernel/trace/trace_events.c | 14 +++ kernel/trace/trace_events_hist.c | 100 +++++++++++++++++++- tools/testing/selftests/ftrace/Makefile | 2 tools/testing/selftests/ftrace/poll.c | 74 +++++++++++++++ .../ftrace/test.d/trigger/trigger-hist-poll.tc | 74 +++++++++++++++ 6 files changed, 275 insertions(+), 3 deletions(-) create mode 100644 tools/testing/selftests/ftrace/poll.c create mode 100644 tools/testing/selftests/ftrace/test.d/trigger/trigger-hist-poll.tc -- Masami Hiramatsu (Google) <mhiramat(a)kernel.org>

5 days, 2 hours

3
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[PATCH 0/5] riscv: add support for Zaamo and Zalrsc extensions

by Clément Léger

Since commit e87412e621f1 ("integrate Zaamo and Zalrsc text (#1304)"), the A extension has been described as a set of instructions provided by Zaamo and Zalrsc. Add these two extensions. This series is based on the Zc one [1]. Link: https://lore.kernel.org/linux-riscv/20240619113529.676940-1-cleger@rivosinc… --- Clément Léger (5): dt-bindings: riscv: add Zaamo and Zalrsc ISA extension description riscv: add parsing for Zaamo and Zalrsc extensions riscv: hwprobe: export Zaamo and Zalrsc extensions RISC-V: KVM: Allow Zaamo/Zalrsc extensions for Guest/VM KVM: riscv: selftests: Add Zaamo/Zalrsc extensions to get-reg-list test Documentation/arch/riscv/hwprobe.rst | 8 ++++++++ .../devicetree/bindings/riscv/extensions.yaml | 19 +++++++++++++++++++ arch/riscv/include/asm/hwcap.h | 2 ++ arch/riscv/include/uapi/asm/hwprobe.h | 2 ++ arch/riscv/include/uapi/asm/kvm.h | 2 ++ arch/riscv/kernel/cpufeature.c | 9 ++++++++- arch/riscv/kernel/sys_hwprobe.c | 2 ++ arch/riscv/kvm/vcpu_onereg.c | 4 ++++ .../selftests/kvm/riscv/get-reg-list.c | 8 ++++++++ 9 files changed, 55 insertions(+), 1 deletion(-) -- 2.45.2

5 days, 10 hours

4
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[PATCH V2] selftests: lsm: Refactor `flags_overset_lsm_set_self_attr` test

by Amit Vadhavana

Remove the temporary context variable `tctx` to simplify the code. use the original context `ctx` directly in calls to `lsm_get_self_attr`, eliminating redundancy without any functional changes. Reviewed-by: Casey Schaufler <casey(a)schaufler-ca.com> Reviewed-by: Shuah Khan <skhan(a)linuxfoundation.org> Signed-off-by: Amit Vadhavana <av2082000(a)gmail.com> --- V1:- https://lore.kernel.org/all/20241112182810.24761-1-av2082000@gmail.com/ V1 -> V2 : write complete sentences instead of bullet points in the change log. --- tools/testing/selftests/lsm/lsm_set_self_attr_test.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/lsm/lsm_set_self_attr_test.c b/tools/testing/selftests/lsm/lsm_set_self_attr_test.c index 66dec47e3ca3..732e89fe99c0 100644 --- a/tools/testing/selftests/lsm/lsm_set_self_attr_test.c +++ b/tools/testing/selftests/lsm/lsm_set_self_attr_test.c @@ -56,16 +56,15 @@ TEST(flags_zero_lsm_set_self_attr) TEST(flags_overset_lsm_set_self_attr) { const long page_size = sysconf(_SC_PAGESIZE); - char *ctx = calloc(page_size, 1); + struct lsm_ctx *ctx = calloc(page_size, 1); __u32 size = page_size; - struct lsm_ctx *tctx = (struct lsm_ctx *)ctx; ASSERT_NE(NULL, ctx); if (attr_lsm_count()) { - ASSERT_LE(1, lsm_get_self_attr(LSM_ATTR_CURRENT, tctx, &size, + ASSERT_LE(1, lsm_get_self_attr(LSM_ATTR_CURRENT, ctx, &size, 0)); } - ASSERT_EQ(-1, lsm_set_self_attr(LSM_ATTR_CURRENT | LSM_ATTR_PREV, tctx, + ASSERT_EQ(-1, lsm_set_self_attr(LSM_ATTR_CURRENT | LSM_ATTR_PREV, ctx, size, 0)); free(ctx); -- 2.25.1

5 days, 19 hours

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1
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Re: [PATCH 2/3] KVM: x86: Add support for VMware guest specific hypercalls

by Doug Covelli

On Wed, Nov 13, 2024 at 2:31 AM Paolo Bonzini <pbonzini(a)redhat.com> wrote: > > > > Il mar 12 nov 2024, 21:44 Doug Covelli <doug.covelli(a)broadcom.com> ha scritto: >> >> > Split irqchip should be the best tradeoff. Without it, moves from cr8 >> > stay in the kernel, but moves to cr8 always go to userspace with a >> > KVM_EXIT_SET_TPR exit. You also won't be able to use Intel >> > flexpriority (in-processor accelerated TPR) because KVM does not know >> > which bits are set in IRR. So it will be *really* every move to cr8 >> > that goes to userspace. >> >> Sorry to hijack this thread but is there a technical reason not to allow CR8 >> based accesses to the TPR (not MMIO accesses) when the in-kernel local APIC is >> not in use? > > > No worries, you're not hijacking :) The only reason is that it would be more code for a seldom used feature and anyway with worse performance. (To be clear, CR8 based accesses are allowed, but stores cause an exit in order to check the new TPR against IRR. That's because KVM's API does not have an equivalent of the TPR threshold as you point out below). I have not really looked at the code but it seems like it could also simplify things as CR8 would be handled more uniformly regardless of who is virtualizing the local APIC. >> Also I could not find these documented anywhere but with MSFT's APIC our monitor >> relies on extensions for trapping certain events such as INIT/SIPI plus LINT0 >> and SVR writes: >> >> UINT64 X64ApicInitSipiExitTrap : 1; // WHvRunVpExitReasonX64ApicInitSipiTrap >> UINT64 X64ApicWriteLint0ExitTrap : 1; // WHvRunVpExitReasonX64ApicWriteTrap >> UINT64 X64ApicWriteLint1ExitTrap : 1; // WHvRunVpExitReasonX64ApicWriteTrap >> UINT64 X64ApicWriteSvrExitTrap : 1; // WHvRunVpExitReasonX64ApicWriteTrap > > > There's no need for this in KVM's in-kernel APIC model. INIT and SIPI are handled in the hypervisor and you can get the current state of APs via KVM_GET_MPSTATE. LINT0 and LINT1 are injected with KVM_INTERRUPT and KVM_NMI respectively, and they obey IF/PPR and NMI blocking respectively, plus the interrupt shadow; so there's no need for userspace to know when LINT0/LINT1 themselves change. The spurious interrupt vector register is also handled completely in kernel. I realize that KVM can handle LINT0/SVR updates themselves but our interrupt subsystem relies on knowing the current values of these registers even when not virtualizing the local APIC. I suppose we could use KVM_GET_LAPIC to sync things up on demand but that seems like it might nor be great from a performance point of view. >> I did not see any similar functionality for KVM. Does anything like that exist? >> In any case we would be happy to add support for handling CR8 accesses w/o >> exiting w/o the in-kernel APIC along with some sort of a way to configure the >> TPR threshold if folks are not opposed to that. > > > As far I know everybody who's using KVM (whether proprietary or open source) has had no need for that, so I don't think it's a good idea to make the API more complex. Performance of Windows guests is going to be bad anyway with userspace APIC. From what I have seen the exit cost with KVM is significantly lower than with WHP/Hyper-V. I don't think performance of Windows guests with userspace APIC emulation would be bad if CR8 exits could be avoided (Linux guests perf isn't bad from what I have observed and the main difference is the astronomical number of CR8 exits). It seems like it would be pretty decent although I agree if you want the absolute best performance then you would want to use the in kernel APIC to speed up handling of ICR/EOI writes but those are relatively infrequent compared to CR8 accesses . Anyway I just saw Sean's response while writing this and it seems he is not in favor of avoiding CR8 exits w/o the in kernel APIC either so I suppose we will have to look into making use of the in kernel APIC. Doug > Paolo > >> Doug >> >> > > For now I think it makes sense to handle BDOOR_CMD_GET_VCPU_INFO at userlevel >> > > like we do on Windows and macOS. >> > > >> > > BDOOR_CMD_GETTIME/BDOOR_CMD_GETTIMEFULL are similar with the former being >> > > deprecated in favor of the latter. Both do essentially the same thing which is >> > > to return the host OS's time - on Linux this is obtained via gettimeofday. I >> > > believe this is mainly used by tools to fix up the VM's time when resuming from >> > > suspend. I think it is fine to continue handling these at userlevel. >> > >> > As long as the TSC is not involved it should be okay. >> > >> > Paolo >> > >> > > > >> Anyway, one question apart from this: is the API the same for the I/O >> > > > >> port and hypercall backdoors? >> > > > > >> > > > > Yeah the calls and arguments are the same. The hypercall based >> > > > > interface is an attempt to modernize the backdoor since as you pointed >> > > > > out the I/O based interface is kind of hacky as it bypasses the normal >> > > > > checks for an I/O port access at CPL3. It would be nice to get rid of >> > > > > it but unfortunately I don't think that will happen in the foreseeable >> > > > > future as there are a lot of existing VMs out there with older SW that >> > > > > still uses this interface. >> > > > >> > > > Yeah, but I think it still justifies that the KVM_ENABLE_CAP API can >> > > > enable the hypercall but not the I/O port. >> > > > >> > > > Paolo >> > >> >> -- >> This electronic communication and the information and any files transmitted >> with it, or attached to it, are confidential and are intended solely for >> the use of the individual or entity to whom it is addressed and may contain >> information that is confidential, legally privileged, protected by privacy >> laws, or otherwise restricted from disclosure to anyone else. If you are >> not the intended recipient or the person responsible for delivering the >> e-mail to the intended recipient, you are hereby notified that any use, >> copying, distributing, dissemination, forwarding, printing, or copying of >> this e-mail is strictly prohibited. If you received this e-mail in error, >> please return the e-mail to the sender, delete it from your computer, and >> destroy any printed copy of it. >> -- This electronic communication and the information and any files transmitted with it, or attached to it, are confidential and are intended solely for the use of the individual or entity to whom it is addressed and may contain information that is confidential, legally privileged, protected by privacy laws, or otherwise restricted from disclosure to anyone else. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, you are hereby notified that any use, copying, distributing, dissemination, forwarding, printing, or copying of this e-mail is strictly prohibited. If you received this e-mail in error, please return the e-mail to the sender, delete it from your computer, and destroy any printed copy of it.

6 days, 14 hours

3
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[PATCH] selftests: arm coresight: sysfsmode testing

by Linu Cherian

Add sysfs mode selftest for ARM Coresight hardware tracer. Signed-off-by: Linu Cherian <lcherian(a)marvell.com> --- .../drivers/hwtracing/coresight/Makefile | 5 + .../hwtracing/coresight/sysfs_test_trace.sh | 144 ++++++++++++++++++ 2 files changed, 149 insertions(+) create mode 100644 tools/testing/selftests/drivers/hwtracing/coresight/Makefile create mode 100755 tools/testing/selftests/drivers/hwtracing/coresight/sysfs_test_trace.sh diff --git a/tools/testing/selftests/drivers/hwtracing/coresight/Makefile b/tools/testing/selftests/drivers/hwtracing/coresight/Makefile new file mode 100644 index 000000000000..7dc68ae1c0a9 --- /dev/null +++ b/tools/testing/selftests/drivers/hwtracing/coresight/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 + +TEST_PROGS = sysfs_test_trace.sh + +include ../../../lib.mk diff --git a/tools/testing/selftests/drivers/hwtracing/coresight/sysfs_test_trace.sh b/tools/testing/selftests/drivers/hwtracing/coresight/sysfs_test_trace.sh new file mode 100755 index 000000000000..0d6307fff1d2 --- /dev/null +++ b/tools/testing/selftests/drivers/hwtracing/coresight/sysfs_test_trace.sh @@ -0,0 +1,144 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2024 Marvell. + +# Test Arm CoreSight trace capture in sysfs mode +# Based on tools/perf/tests/shell/test_arm_coresight.sh + +glb_err=0 + +arm_cs_report() { + if [ $2 != 0 ]; then + echo "$1: FAIL" + glb_err=$2 + else + echo "$1: PASS" + fi +} + +is_device_sink() { + # If the node of "enable_sink" is existed under the device path, this + # means the device is a sink device. + + if [ -e "$1/enable_sink" ]; then + + return 0 + else + return 1 + fi +} + +# Configure sink for buffer mode +cfg_sink_buf_mode() { + sink_dev=$1 + mode=$2 + # Set buffer mode if supported + if [ -e "$sink_dev/buf_modes_available" ]; then + cat $sink_dev/buf_modes_available | grep -E -q $mode + if [ $? -eq 0 ]; then + echo $mode > $sink_dev/buf_mode_preferred + return 0 + fi + fi + + return 1 +} + +run_app() { + + taskset -c $1 dd if=/dev/urandom of=/dev/null bs=1M count=64 +} + +sysfs_trace() { + src_dev=$1 + sink_dev=$2 + cpu=$3 + + # Enable sink device + echo 1 > $sink_dev/enable_sink + # Enable source device + echo 1 > $src_dev/enable_source + + # Run app to be traced + run_app $cpu + + # Read back trace data + dd if=/dev/$sink_dev_name of=/tmp/tracedata + + # Verify if read is successful + err=$? + + # Disable source device + echo 0 > $src_dev/enable_source + + # Diskable sink device + echo 0 > $sink_dev/enable_sink + + arm_cs_report "CoreSight path testing (CPU$cpu -> $sink_dev_name)" $err +} + +try_sysfs_trace_resrv_buf() { + src_dev=$1 + sink_dev=$2 + cpu=$3 + + # Configure the resrved buffer mode if available + cfg_sink_buf_mode $sink_dev "resrv" + if [ $? -eq 0 ]; then + echo "Running sysfs trace with resrv buf mode" + sysfs_trace $src_dev $sink_dev $cpu + # Restore buffer mode + cfg_sink_buf_mode $sink_dev "auto" + if [ $? -eq 1 ]; then + echo "Failed to restore default buf mode" + fi + fi +} + +arm_cs_iterate_devices() { + src_dev=$1 + cpu=$3 + for cdev in $2/connections/out\:*; do + + # Skip testing if it's not a directory + ! [ -d $cdev ] && continue; + + # Read out its symbol link file name + sink_dev=`readlink -f $cdev` + + # Extract device name from path, e.g. + # sink_dev = '/sys/devices/platform/20010000.etf/tmc_etf0' + # `> sink_dev_name = 'tmc_etf0' + sink_dev_name=$(basename $sink_dev) + + if is_device_sink $sink_dev; then + # Run trace with resrv buf mode (if available) + try_sysfs_trace_resrv_buf $src_dev $sink_dev $cpu + + # Run the default mode + echo "Running sysfs trace with default settings" + sysfs_trace $src_dev $sink_dev $cpu + fi + + arm_cs_iterate_devices $src_dev $cdev $cpu + + done +} + +arm_cs_etm_traverse_path_test() { + # Iterate for every ETM device + for dev in /sys/bus/event_source/devices/cs_etm/cpu*; do + # Canonicalize the path + dev=`readlink -f $dev` + + # Find the ETM device belonging to which CPU + cpu=`cat $dev/cpu` + + # Use depth-first search (DFS) to iterate outputs + arm_cs_iterate_devices $dev $dev $cpu + done +} + +arm_cs_etm_traverse_path_test + +exit $glb_err -- 2.34.1

1 week, 1 day

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[PATCH v2 0/6] Enhance event delivery error handling

by Ivan Orlov

Currently, the situation when guest accesses MMIO during vectoring is handled differently on VMX and SVM: on VMX KVM returns internal error, when SVM goes into infinite loop trying to deliver an event again and again. This patch series eliminates this difference by returning a KVM internal error when guest performs MMIO during vectoring for both VMX and SVM. Also, introduce a selftest test case which covers the error handling mentioned above. V1 -> V2: - Make commit messages more brief, avoid using pronouns - Extract SVM error handling into a separate commit - Introduce a new X86EMUL_ return type and detect the unhandleable vectoring error in vendor-specific check_emulate_instruction instead of handling it in the common MMU code (which is specific for cached MMIO) Ivan Orlov (6): KVM: x86: Add function for vectoring error generation KVM: x86: Add emulation status for vectoring during MMIO KVM: VMX: Handle vectoring error in check_emulate_instruction KVM: SVM: Handle MMIO during vectroing error selftests: KVM: extract lidt into helper function selftests: KVM: Add test case for MMIO during vectoring arch/x86/include/asm/kvm_host.h | 12 ++++- arch/x86/kvm/kvm_emulate.h | 2 + arch/x86/kvm/svm/svm.c | 9 +++- arch/x86/kvm/vmx/vmx.c | 33 +++++------- arch/x86/kvm/x86.c | 27 ++++++++++ .../selftests/kvm/include/x86_64/processor.h | 7 +++ .../selftests/kvm/set_memory_region_test.c | 53 ++++++++++++++++++- .../selftests/kvm/x86_64/sev_smoke_test.c | 2 +- 8 files changed, 119 insertions(+), 26 deletions(-) -- 2.43.0

1 week, 3 days

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[PATCH V2 0/4] A few fixes for RISC-V

by Chunyan Zhang

These patches are all simple fixes with no strong dependency though, I hope that making them a patchset will be more convenient for merge. The patchset are based on v6.12-rc2. Chunyan Zhang (4): riscv: Remove unused GENERATING_ASM_OFFSETS riscv: Remove duplicated GET_RM selftest/mm: Fix typo in virtual_address_range selftests/mm: skip virtual_address_range tests on riscv arch/riscv/kernel/asm-offsets.c | 2 -- arch/riscv/kernel/traps_misaligned.c | 2 -- tools/testing/selftests/mm/Makefile | 2 ++ tools/testing/selftests/mm/run_vmtests.sh | 10 ++++++---- tools/testing/selftests/mm/virtual_address_range.c | 4 ++-- 5 files changed, 10 insertions(+), 10 deletions(-) -- 2.34.1

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Linux-kselftest-mirror November 2024