Commit 00e07787 authored Sep 10, 2024 by Suzuki K Poulose Committed by Junhao He Sep 10, 2024

coresight: etm4x: Fix access to resource selector registers

mainline inclusion
from mainline-v6.10-rc1
commit d6fc00d0f640d6010b51054aa8b0fd191177dbc9
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAKVFA
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d6fc00d0f640d6010b51054aa8b0fd191177dbc9



--------------------------------

Resource selector pair 0 is always implemented and reserved. We must not
touch it, even during save/restore for CPU Idle. Rest of the driver is
well behaved. Fix the offending ones.

Reported-by: Yabin Cui <yabinc@google.com>
Fixes: f188b5e7 ("coresight: etm4x: Save/restore state across CPU low power states")
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Yabin Cui <yabinc@google.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20240412142702.2882478-5-suzuki.poulose@arm.com


Signed-off-by: Junhao He <hejunhao3@huawei.com>

parent 585bf074

drivers/hwtracing/coresight/coresight-etm4x-core.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -1671,7 +1671,8 @@ static int __etm4_cpu_save(struct etmv4_drvdata *drvdata)
		state->trccntvr[i] = etm4x_read32(csa, TRCCNTVRn(i));
		}

		for (i = 0; i < drvdata->nr_resource * 2; i++)
		/* Resource selector pair 0 is reserved */
		for (i = 2; i < drvdata->nr_resource * 2; i++)
		state->trcrsctlr[i] = etm4x_read32(csa, TRCRSCTLRn(i));

		for (i = 0; i < drvdata->nr_ss_cmp; i++) {
		@@ -1801,7 +1802,8 @@ static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata)
		etm4x_relaxed_write32(csa, state->trccntvr[i], TRCCNTVRn(i));
		}

		for (i = 0; i < drvdata->nr_resource * 2; i++)
		/* Resource selector pair 0 is reserved */
		for (i = 2; i < drvdata->nr_resource * 2; i++)
		etm4x_relaxed_write32(csa, state->trcrsctlr[i], TRCRSCTLRn(i));

		for (i = 0; i < drvdata->nr_ss_cmp; i++) {