From 6bd243d5abd91ee7d7fa58a9ed60381da49b4b0a Mon Sep 17 00:00:00 2001 From: Muralidhara M K Date: Thu, 23 Jul 2026 15:16:54 +0530 Subject: [PATCH] platform/x86/amd/hsmp: Clear mdev.this_device on deregister MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit misc_deregister() destroys the device but leaves miscdevice.this_device pointing at the freed struct device. Clear it so any later check of this_device, and a subsequent re-register, does not observe a stale pointer. An upcoming change uses this_device to track whether /dev/hsmp is registered across the shared ACPI sockets and relies on it being NULL after deregister. Signed-off-by: Muralidhara M K Link: https://patch.msgid.link/20260723094656.3806028-5-muralidhara.mk@amd.com Signed-off-by: Ilpo Järvinen --- drivers/platform/x86/amd/hsmp/hsmp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c b/drivers/platform/x86/amd/hsmp/hsmp.c index fd36c8f142c0..584fd9b1d31f 100644 --- a/drivers/platform/x86/amd/hsmp/hsmp.c +++ b/drivers/platform/x86/amd/hsmp/hsmp.c @@ -539,6 +539,7 @@ EXPORT_SYMBOL_NS_GPL(hsmp_misc_register, "AMD_HSMP"); void hsmp_misc_deregister(void) { misc_deregister(&hsmp_pdev.mdev); + hsmp_pdev.mdev.this_device = NULL; } EXPORT_SYMBOL_NS_GPL(hsmp_misc_deregister, "AMD_HSMP");