On 08/05/2026 6:45 am, Jie Gan wrote:
> When coresight_path_assign_trace_id() fails to allocate a valid trace
> ID, the code jumps to err_path without setting ret to an error value.
> This causes coresight_enable_sysfs() to return 0 (success) to the
> caller even though no trace session was started.
>
> Set ret = -EINVAL before the goto so that callers receive a proper
> error code.
>
> Fixes: d87d76d823d1 ("Coresight: Allocate trace ID after building the path")
> Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com>
> ---
> drivers/hwtracing/coresight/coresight-sysfs.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c b/drivers/hwtracing/coresight/coresight-sysfs.c
> index d2a6ed8bcc74..c9338c783540 100644
> --- a/drivers/hwtracing/coresight/coresight-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-sysfs.c
> @@ -195,42 +195,44 @@ int coresight_enable_sysfs(struct coresight_device *csdev)
> */
> if (subtype == CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE)
> csdev->refcnt++;
> goto out;
> }
>
> sink = coresight_find_activated_sysfs_sink(csdev);
> if (!sink) {
> ret = -EINVAL;
> goto out;
> }
>
> path = coresight_build_path(csdev, sink);
> if (IS_ERR(path)) {
> pr_err("building path(s) failed\n");
> ret = PTR_ERR(path);
> goto out;
> }
>
> coresight_path_assign_trace_id(path, CS_MODE_SYSFS);
> - if (!IS_VALID_CS_TRACE_ID(path->trace_id))
> + if (!IS_VALID_CS_TRACE_ID(path->trace_id)) {
> + ret = -EINVAL;
> goto err_path;
> + }
>
> ret = coresight_enable_path(path, CS_MODE_SYSFS);
> if (ret)
> goto err_path;
>
> ret = coresight_enable_source_sysfs(csdev, CS_MODE_SYSFS, path);
> if (ret)
> goto err_source;
>
> switch (subtype) {
> case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
> /*
> * When working from sysFS it is important to keep track
> * of the paths that were created so that they can be
> * undone in 'coresight_disable()'. Since there can only
> * be a single session per tracer (when working from sysFS)
> * a per-cpu variable will do just fine.
> */
> cpu = source_ops(csdev)->cpu_id(csdev);
> per_cpu(tracer_path, cpu) = path;
>
> ---
> base-commit: 17c7841d09ee7d33557fd075562d9289b6018c90
> change-id: 20260508-fix-trace-id-error-dbfdd4d8f2d1
>
> Best regards,
Reviewed-by: James Clark <james.clark(a)linaro.org>
On Mon, May 11, 2026 at 05:28:37PM +0800, Jie Gan wrote:
> Hi Leo,
>
> On 5/11/2026 5:24 PM, Leo Yan wrote:
> > On Mon, May 11, 2026 at 05:04:44PM +0800, Jie Gan wrote:
> > > In coresight_enable_sysfs(), for non-CPU sources (SOFTWARE, TPDM,
> > > OTHERS), the source device is enabled via coresight_enable_source_sysfs()
> > > before idr_alloc_u32() maps the path. If idr_alloc_u32() fails, the
> > > original code jumped directly to err_source, which only calls
> > > coresight_disable_path() and coresight_release_path(). The source device
> > > was left enabled with an incremented refcnt but no path tracked for it,
> > > leaving the device in an inconsistent state.
> > >
> > > Disable the source before jumping to err_source so the enable and path
> > > operations are fully unwound.
> > >
> > > Fixes: 1f5149c7751c ("coresight: Move all sysfs code to sysfs file")
> > > Signed-off-by: Jie Gan <quic_jiegan(a)quicinc.com>
> >
> > Actually I have noticed this. Since my PM series will remove IDR things,
> > and I don't think anyone really hit idr alloc error, this is why I
> > didn't send fix for this.
> >
> > Anyway, this is a reasonable fix. I will send out my PM series later
> > in today, I will pick this patch into my series and rebase on it, hope
> > this is easier for all of us.
>
> Well noted. Please feel free to pick it into your series.
Thanks! Just note, I updated the Fixes tag as:
Fixes: 5c0016d7b343 ("coresight: core: Use IDR for non-cpu bound sources' paths.")
Which is the original patch for the issue.
Thanks,
Leo
On Mon, May 11, 2026 at 05:04:44PM +0800, Jie Gan wrote:
> In coresight_enable_sysfs(), for non-CPU sources (SOFTWARE, TPDM,
> OTHERS), the source device is enabled via coresight_enable_source_sysfs()
> before idr_alloc_u32() maps the path. If idr_alloc_u32() fails, the
> original code jumped directly to err_source, which only calls
> coresight_disable_path() and coresight_release_path(). The source device
> was left enabled with an incremented refcnt but no path tracked for it,
> leaving the device in an inconsistent state.
>
> Disable the source before jumping to err_source so the enable and path
> operations are fully unwound.
>
> Fixes: 1f5149c7751c ("coresight: Move all sysfs code to sysfs file")
> Signed-off-by: Jie Gan <quic_jiegan(a)quicinc.com>
Actually I have noticed this. Since my PM series will remove IDR things,
and I don't think anyone really hit idr alloc error, this is why I
didn't send fix for this.
Anyway, this is a reasonable fix. I will send out my PM series later
in today, I will pick this patch into my series and rebase on it, hope
this is easier for all of us.
Thanks,
Leo
On Fri, May 08, 2026 at 01:45:35PM +0800, Jie Gan wrote:
[...]
> coresight_path_assign_trace_id(path, CS_MODE_SYSFS);
> - if (!IS_VALID_CS_TRACE_ID(path->trace_id))
> + if (!IS_VALID_CS_TRACE_ID(path->trace_id)) {
> + ret = -EINVAL;
> goto err_path;
> + }
On the top of this patch, could we do a further improvement?
Move IS_VALID_CS_TRACE_ID() into coresight_path_assign_trace_id() and
return 0 for success and < 0 for failures. As result, callers only
need to check the returned value.
For this patch:
Reviewed-by: Leo Yan <leo.yan(a)arm.com>
On Thu, May 07, 2026 at 03:55:26PM +0100, James Clark wrote:
[...]
> Hi Leo,
>
> Testing on the Orion O6 board was all good, and so was stress testing
> concurrent sysfs mode and hotplug on Juno.
Thanks a lot for test!
> However, I was trying to stress test sysfs mode and rmmod on Juno and
> ran into an issue, although a similar issue is present without your
> patchset.
I don't think CPU PM introduces additional complexity for the above cases.
The reason is that CPU PM notifiers _only_ apply to active sessions, and
once a device is enabled, the module cannot be removed.
If the race conditions between enabling/disabling sessions and module
load/unload are properly handled, CPU PM should be safe. If we have bug
in these race conditions, the high frequency data access in CPU PM may
expose the issues - I don't expect CPU PM is the culprit.
> If you run an rmmod on all the coresight devices at the same time as an
> enable_source / disable loop you always get this:
>
> WARNING: possible circular locking dependency detected
> 7.0.0-rc1+ #713 Tainted: G N
> ------------------------------------------------------
> rmmod/1361 is trying to acquire lock:
> ffff0008042f69a8 (kn->active#144){++++}-{0:0}, at:
> __kernfs_remove+0x1b8/0x2c8
kn->active is not a lock but an active reference of sysfs node, but it
use lockdep annotation to detect lock dependency.
> Possible unsafe locking scenario:
> CPU0 CPU1
> ---- ----
> lock(coresight_mutex);
> lock(cpu_hotplug_lock);
> lock(coresight_mutex);
> lock(kn->active#144);
> *** DEADLOCK ***
The potential deadlock sequence could be:
kernfs_fop_write_iter()
`> kernfs_get_active_of() => acquire kn->active
`> coresight_enable_sysfs() => acquire coresight_mutex
coresight_unregister() => acquire coresight_mutex
`> device_unregister()
`> __kernfs_remove()
`> kernfs_drain() => acquire kn->active
> I think the issue can be fixed by releasing the coresight_mutex before
> device_unregister():
>
> diff --git a/drivers/hwtracing/coresight/coresight-core.c
> b/drivers/hwtracing/coresight/coresight-core.c
> index 015363da12fa..620560880f12 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -1639,8 +1639,8 @@ void coresight_unregister(struct coresight_device
> *csdev)
> coresight_remove_conns(csdev);
> coresight_clear_default_sink(csdev);
> coresight_release_platform_data(csdev->dev.parent, csdev->pdata);
> - device_unregister(&csdev->dev);
> mutex_unlock(&coresight_mutex);
> + device_unregister(&csdev->dev);
> }
> EXPORT_SYMBOL_GPL(coresight_unregister);
If so, we also need to move device_register() out of the mutex scope.
That said, I still think we should dive a bit if can use smaller locking
granluarity (combining with bus management provided by device model).
> Although I didn't think too hard about the implications, but it might be ok
> because once all the connections are removed the device can't be used so
> releasing the coresight_mutex isn't an issue.
>
> But then testing that I ran into some kind of refleak where I couldn't
> unload modules anymore, even though I'd disabled everything. But that could
> be a different issue:
>
> rmmod: ERROR: Module coresight_funnel is in use
> rmmod: ERROR: Module coresight_replicator is in use
> rmmod: ERROR: Module coresight_etm4x is in use
> rmmod: ERROR: Module coresight_tmc is in use
> rmmod: ERROR: Module coresight_cti is in use
> rmmod: ERROR: Module coresight is in use by: coresight_tmc coresight_cti
> coresight_etm4x coresight_replicator coresight_funnel
I suspect this is due to module references are not properly released, or
the entire CS path is not properly disabled.
After the issue occurs, can the ETM sysfs knob still be accessed? I am
curious whether this is caused by the sysfs knob disappearing so no way
to disable the path or the sysfs knob still exists but the driver
internally misses to disable the path.
> Anyway I don't think your patches make this worse, so we can probably ignore
> it, but it would be good to be able to stress test the new modifications
> around the same area.
As no regression in test, I agree that we should not defer this series.
We can fix the race with module load/unload as a separate task:
- sysfs mode + module load/unload
- perf mode + module load/unload
Then we can combine stress test with CPU idle/hotplug.
Thanks,
Leo
On 09/05/2026 1:58 am, Jie Gan wrote:
> When coresight_path_assign_trace_id() cannot assign a valid trace ID,
> coresight_enable_sysfs() takes the err_path goto with ret still 0,
> returning success to the caller despite no trace session being started.
>
> Fix this by changing coresight_path_assign_trace_id() to return int.
> Move the IS_VALID_CS_TRACE_ID() check inside the function so it returns
> -EINVAL on failure and 0 on success. Update coresight_enable_sysfs() to
> check the return value directly instead of inspecting path->trace_id
> after the call.
>
> The other caller in coresight-etm-perf.c discards the return value and
> continues to check path->trace_id via IS_VALID_CS_TRACE_ID() directly.
> This is unaffected: on failure path->trace_id is no longer written, so
> it remains 0, which IS_VALID_CS_TRACE_ID() rejects the same as before.
>
> Fixes: d87d76d823d1 ("Coresight: Allocate trace ID after building the path")
> Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com>
> ---
> Changes in v2:
> - Refactor the coresight_path_assign_trace_id function.
> - Link to v1: https://lore.kernel.org/r/20260508-fix-trace-id-error-v1-1-5f11a5456fdf@oss…
> ---
> drivers/hwtracing/coresight/coresight-core.c | 14 ++++++++++----
> drivers/hwtracing/coresight/coresight-priv.h | 2 +-
> drivers/hwtracing/coresight/coresight-sysfs.c | 4 ++--
> 3 files changed, 13 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index 46f247f73cf6..cabdc0c72f38 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -739,12 +739,12 @@ static int coresight_get_trace_id(struct coresight_device *csdev,
> * Call this after creating the path and before enabling it. This leaves
> * the trace ID set on the path, or it remains 0 if it couldn't be assigned.
> */
> -void coresight_path_assign_trace_id(struct coresight_path *path,
> +int coresight_path_assign_trace_id(struct coresight_path *path,
> enum cs_mode mode)
> {
> struct coresight_device *sink = coresight_get_sink(path);
> struct coresight_node *nd;
> - int trace_id;
> + int trace_id, ret = -EINVAL;
>
> list_for_each_entry(nd, &path->path_list, link) {
> /* Assign a trace ID to the path for the first device that wants to do it */
> @@ -755,10 +755,16 @@ void coresight_path_assign_trace_id(struct coresight_path *path,
> * Non 0 is either success or fail.
> */
> if (trace_id != 0) {
> - path->trace_id = trace_id;
> - return;
> + if (IS_VALID_CS_TRACE_ID(trace_id)) {
> + path->trace_id = trace_id;
> + ret = 0;
Reviewed-by: James Clark <james.clark(a)linaro.org>
Minor nit, but just "return 0" here is a bit simpler.
> + }
> +
> + return ret;
And then "return -EINVAL" for these ones.
> }
> }
> +
> + return ret; > }
>
> /**
> diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
> index 1ea882dffd70..34c7e792adbd 100644
> --- a/drivers/hwtracing/coresight/coresight-priv.h
> +++ b/drivers/hwtracing/coresight/coresight-priv.h
> @@ -153,7 +153,7 @@ int coresight_make_links(struct coresight_device *orig,
> void coresight_remove_links(struct coresight_device *orig,
> struct coresight_connection *conn);
> u32 coresight_get_sink_id(struct coresight_device *csdev);
> -void coresight_path_assign_trace_id(struct coresight_path *path,
> +int coresight_path_assign_trace_id(struct coresight_path *path,
> enum cs_mode mode);
>
> #if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM3X)
> diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c b/drivers/hwtracing/coresight/coresight-sysfs.c
> index d2a6ed8bcc74..b6a870399e83 100644
> --- a/drivers/hwtracing/coresight/coresight-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-sysfs.c
> @@ -211,8 +211,8 @@ int coresight_enable_sysfs(struct coresight_device *csdev)
> goto out;
> }
>
> - coresight_path_assign_trace_id(path, CS_MODE_SYSFS);
> - if (!IS_VALID_CS_TRACE_ID(path->trace_id))
> + ret = coresight_path_assign_trace_id(path, CS_MODE_SYSFS);
> + if (ret)
> goto err_path;
>
> ret = coresight_enable_path(path, CS_MODE_SYSFS);
>
> ---
> base-commit: 17c7841d09ee7d33557fd075562d9289b6018c90
> change-id: 20260508-fix-trace-id-error-dbfdd4d8f2d1
>
> Best regards,
On Wed, Apr 22, 2026 at 02:21:54PM +0100, Yeoreum Yun wrote:
[...]
> @@ -573,11 +573,9 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
> etm4x_relaxed_write32(csa, config->res_ctrl[i], TRCRSCTLRn(i));
>
> for (i = 0; i < caps->nr_ss_cmp; i++) {
> - /* always clear status bit on restart if using single-shot */
> - if (config->ss_ctrl[i] || config->ss_pe_cmp[i])
> - config->ss_status[i] &= ~TRCSSCSRn_STATUS;
> etm4x_relaxed_write32(csa, config->ss_ctrl[i], TRCSSCCRn(i));
> - etm4x_relaxed_write32(csa, config->ss_status[i], TRCSSCSRn(i));
> + /* always clear status and pending bits on restart if using single-shot */
> + etm4x_relaxed_write32(csa, 0x0, TRCSSCSRn(i));
After confirmed with hardware team, we should preserve status bits
(including STATUS and PENDING bits) during a session. So here we should
set drvdata->ss_status to TRCSSCSRn.
> @@ -1503,8 +1501,9 @@ static void etm4_init_arch_data(void *info)
> */
> caps->nr_ss_cmp = FIELD_GET(TRCIDR4_NUMSSCC_MASK, etmidr4);
> for (i = 0; i < caps->nr_ss_cmp; i++) {
> - drvdata->config.ss_status[i] =
> - etm4x_relaxed_read32(csa, TRCSSCSRn(i));
> + drvdata->ss_status[i] = etm4x_relaxed_read32(csa, TRCSSCSRn(i));
> + drvdata->ss_status[i] &= (TRCSSCSRn_PC | TRCSSCSRn_DV |
> + TRCSSCSRn_DA | TRCSSCSRn_INST);
It is fine for read these capacity bits when probe, but we need to clear
status when a session is starting to avoid the stale value left from
previous session:
drvdata->ss_status[idx] &= ~(TRCSSCSRn_STATUS | TRCSSCSRn_PENDING);
We can do this in etm4_parse_event_config() for perf mode, and might
create a new function (say etm4_parse_sysfs_config()) for preparing
config for sysfs mode?
The rest looks good to me.
Thanks,
Leo
System register ETMs and ETE are unlikely to be preserved on CPU power
down. The ETE DT binding also never documented
"arm,coresight-loses-context-with-cpu" so nobody would have legitimately
been able to use that binding to fix it and ACPI has no such binding at
all.
Fix it by hard coding the setting for sysreg ETMs (ETE is always sysreg)
or ACPI boots. Use a local variable when setting up save_state so that
it's immune to concurrent probing when devices have different
configurations which is an issue with modifying the global.
This fixes the following error when using Coresight with ACPI on the FVP
which supports CPU PM:
coresight ete0: External agent took claim tag
WARNING: drivers/hwtracing/coresight/coresight-core.c:248 at coresight_disclaim_device_unlocked+0xe0/0xe8, CPU#0: perf/117
Fixes: 35e1c9163e02 ("coresight: ete: Add support for ETE tracing")
Signed-off-by: James Clark <james.clark(a)linaro.org>
---
Fix PM save on ETE, which is an issue that showed up on the FVP when
booted with ACPI and the newly enabled idle states.
---
Changes in v3:
- Setup using a local variable and then check drvdata->save_state
at runtime so it's immune to concurrent probing with different
configs.
- Link to v2: https://lore.kernel.org/r/20260505-james-cs-ete-pm_save_enable-v2-1-d39c1f1…
Changes in v2:
- Expand rule to also save for ACPI and sysreg ETMs. Now module param is
only read for MMIO ETMs and DT.
- Drop change to save the result in drvdata as the single global is
simpler.
- Link to v1: https://lore.kernel.org/r/20260428-james-cs-ete-pm_save_enable-v1-0-c7a90ca…
---
drivers/hwtracing/coresight/coresight-etm4x-core.c | 48 +++++++++++++++-------
1 file changed, 34 insertions(+), 14 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index d565a73f0042..591dfe0bc635 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -56,10 +56,14 @@ MODULE_PARM_DESC(boot_enable, "Enable tracing on boot");
#define PARAM_PM_SAVE_NEVER 1 /* never save any state */
#define PARAM_PM_SAVE_SELF_HOSTED 2 /* save self-hosted state only */
+/*
+ * Save option for ETM4. ETE, sysreg ETM4s and ACPI boots ignore this option and
+ * will always save.
+ */
static int pm_save_enable = PARAM_PM_SAVE_FIRMWARE;
module_param(pm_save_enable, int, 0444);
MODULE_PARM_DESC(pm_save_enable,
- "Save/restore state on power down: 1 = never, 2 = self-hosted");
+ "Save/restore state on power down: 1 = never, 2 = self-hosted. MMIO and DT only.");
static struct etmv4_drvdata *etmdrvdata[NR_CPUS];
static void etm4_set_default_config(struct etmv4_config *config);
@@ -2012,7 +2016,7 @@ static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
{
int ret = 0;
- if (pm_save_enable != PARAM_PM_SAVE_SELF_HOSTED)
+ if (!drvdata->save_state)
return 0;
/*
@@ -2127,7 +2131,7 @@ static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata)
static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
{
- if (pm_save_enable != PARAM_PM_SAVE_SELF_HOSTED)
+ if (!drvdata->save_state)
return;
if (coresight_get_mode(drvdata->csdev))
@@ -2212,6 +2216,17 @@ static void etm4_pm_clear(void)
}
}
+static bool etm4x_always_pm_save(struct device *dev, struct csdev_access *csa)
+{
+ /*
+ * Only IO mem ETM devices will benefit from skipping PM save and only
+ * DT has the option to control it, not ACPI. Otherwise system register
+ * based ETMs and ETEs will always lose context on CPU power down, so
+ * always save.
+ */
+ return !csa->io_mem || is_acpi_device_node(dev_fwnode(dev));
+}
+
static int etm4_add_coresight_dev(struct etm4_init_arg *init_arg)
{
int ret;
@@ -2221,6 +2236,7 @@ static int etm4_add_coresight_dev(struct etm4_init_arg *init_arg)
struct coresight_desc desc = { 0 };
u8 major, minor;
char *type_name;
+ bool pm_save;
if (!drvdata)
return -EINVAL;
@@ -2248,6 +2264,21 @@ static int etm4_add_coresight_dev(struct etm4_init_arg *init_arg)
etm4_set_default(&drvdata->config);
+ if (etm4x_always_pm_save(dev, init_arg->csa))
+ pm_save = true;
+ else if (pm_save_enable == PARAM_PM_SAVE_FIRMWARE)
+ pm_save = coresight_loses_context_with_cpu(dev);
+ else
+ pm_save = pm_save_enable != PARAM_PM_SAVE_NEVER;
+
+ if (pm_save) {
+ drvdata->save_state = devm_kmalloc(dev,
+ sizeof(struct etmv4_save_state),
+ GFP_KERNEL);
+ if (!drvdata->save_state)
+ return -ENOMEM;
+ }
+
pdata = coresight_get_platform_data(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
@@ -2305,17 +2336,6 @@ static int etm4_probe(struct device *dev)
if (ret)
return ret;
- if (pm_save_enable == PARAM_PM_SAVE_FIRMWARE)
- pm_save_enable = coresight_loses_context_with_cpu(dev) ?
- PARAM_PM_SAVE_SELF_HOSTED : PARAM_PM_SAVE_NEVER;
-
- if (pm_save_enable != PARAM_PM_SAVE_NEVER) {
- drvdata->save_state = devm_kmalloc(dev,
- sizeof(struct etmv4_save_state), GFP_KERNEL);
- if (!drvdata->save_state)
- return -ENOMEM;
- }
-
raw_spin_lock_init(&drvdata->spinlock);
drvdata->cpu = coresight_get_cpu(dev);
---
base-commit: 971f3474f8898ae8bbab19a9b547819a5e6fbcf1
change-id: 20260420-james-cs-ete-pm_save_enable-4e994e35cdac
Best regards,
--
James Clark <james.clark(a)linaro.org>
When specifying a 2GB AUX buffer, the ETR driver ends up allocating only
a 1MB buffer instead:
# echo 'file coresight-tmc-etr.c +p' > \
/sys/kernel/debug/dynamic_debug/control
# perf record -e cs_etm/@tmc_etr0,timestamp=0/u -C 0 -m ,2G -- test
coresight tmc_etr0: allocated buffer of size 1024KB in mode 0
The page index is an 'int' type, and shifting it by PAGE_SHIFT overflows
when the resulting value exceeds 2GB. This produces a negative value,
causing the driver to fall back to the minimum buffer size (1MB).
Cast the page index to a wider type to accommodate large buffer sizes.
Also fix a similar issue in the buffer offset calculation.
Reported-by: Michiel van Tol <michiel.vantol(a)arm.com>
Fixes: 99443ea19e8b ("coresight: Add generic TMC sg table framework")
Fixes: eebe8dbd8630 ("coresight: tmc: Decouple the perf buffer allocation from sysfs mode")
Signed-off-by: Leo Yan <leo.yan(a)arm.com>
---
drivers/hwtracing/coresight/coresight-tmc-etr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index cee82e52c4ea96b035f1db71b2d9a006bfc1c51e..990bbb721e1d712d7b93f1e36087fdaf9d3baa3b 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -154,7 +154,7 @@ tmc_pages_get_offset(struct tmc_pages *tmc_pages, dma_addr_t addr)
for (i = 0; i < tmc_pages->nr_pages; i++) {
page_start = tmc_pages->daddrs[i];
if (addr >= page_start && addr < (page_start + PAGE_SIZE))
- return i * PAGE_SIZE + (addr - page_start);
+ return (long)i * PAGE_SIZE + (addr - page_start);
}
return -EINVAL;
@@ -1381,7 +1381,7 @@ alloc_etr_buf(struct tmc_drvdata *drvdata, struct perf_event *event,
node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu);
/* Use the minimum limit if the required size is smaller */
- size = nr_pages << PAGE_SHIFT;
+ size = (ssize_t)nr_pages << PAGE_SHIFT;
size = max_t(ssize_t, size, TMC_ETR_PERF_MIN_BUF_SIZE);
/*
---
base-commit: eebe8dbd8630f51cf70b1f68a440cd3d7f7a914d
change-id: 20260217-arm_coresight_fix_big_buffer_size-a8a41298369d
Best regards,
--
Leo Yan <leo.yan(a)arm.com>
