linux-kernel - [PATCH v5 4/7] crypto: ccp: Register SNP panic notifier only if SNP is enabled

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <29e8c21eae96b2cbe0614d04cfa1014b424134b1.1740512583.git.ashish.kalra@amd.com>
Date: Tue, 25 Feb 2025 21:00:47 +0000
From: Ashish Kalra <Ashish.Kalra@....com>
To: <seanjc@...gle.com>, <pbonzini@...hat.com>, <tglx@...utronix.de>,
	<mingo@...hat.com>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>,
	<x86@...nel.org>, <hpa@...or.com>, <thomas.lendacky@....com>,
	<john.allen@....com>, <herbert@...dor.apana.org.au>
CC: <michael.roth@....com>, <dionnaglaze@...gle.com>, <nikunj@....com>,
	<ardb@...nel.org>, <kevinloughlin@...gle.com>, <Neeraj.Upadhyay@....com>,
	<aik@....com>, <kvm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-crypto@...r.kernel.org>, <linux-coco@...ts.linux.dev>
Subject: [PATCH v5 4/7] crypto: ccp: Register SNP panic notifier only if SNP is enabled

From: Ashish Kalra <ashish.kalra@....com>

Currently, the SNP panic notifier is registered on module initialization
regardless of whether SNP is being enabled or initialized.

Instead, register the SNP panic notifier only when SNP is actually
initialized and unregister the notifier when SNP is shutdown.

Reviewed-by: Dionna Glaze <dionnaglaze@...gle.com>
Reviewed-by: Alexey Kardashevskiy <aik@....com>
Signed-off-by: Ashish Kalra <ashish.kalra@....com>
---
 drivers/crypto/ccp/sev-dev.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index c784de6c77c3..b3479a2896d0 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -109,6 +109,13 @@ static void *sev_init_ex_buffer;
  */
 static struct sev_data_range_list *snp_range_list;
 
+static int snp_shutdown_on_panic(struct notifier_block *nb,
+				 unsigned long reason, void *arg);
+
+static struct notifier_block snp_panic_notifier = {
+	.notifier_call = snp_shutdown_on_panic,
+};
+
 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
 {
 	struct sev_device *sev = psp_master->sev_data;
@@ -1198,6 +1205,9 @@ static int __sev_snp_init_locked(int *error)
 	dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
 		 sev->api_minor, sev->build);
 
+	atomic_notifier_chain_register(&panic_notifier_list,
+				       &snp_panic_notifier);
+
 	sev_es_tmr_size = SNP_TMR_SIZE;
 
 	return 0;
@@ -1754,6 +1764,9 @@ static int __sev_snp_shutdown_locked(int *error, bool panic)
 	sev->snp_initialized = false;
 	dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
 
+	atomic_notifier_chain_unregister(&panic_notifier_list,
+					 &snp_panic_notifier);
+
 	/* Reset TMR size back to default */
 	sev_es_tmr_size = SEV_TMR_SIZE;
 
@@ -2481,10 +2494,6 @@ static int snp_shutdown_on_panic(struct notifier_block *nb,
 	return NOTIFY_DONE;
 }
 
-static struct notifier_block snp_panic_notifier = {
-	.notifier_call = snp_shutdown_on_panic,
-};
-
 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
 				void *data, int *error)
 {
@@ -2533,8 +2542,6 @@ void sev_pci_init(void)
 	dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ?
 		"-SNP" : "", sev->api_major, sev->api_minor, sev->build);
 
-	atomic_notifier_chain_register(&panic_notifier_list,
-				       &snp_panic_notifier);
 	return;
 
 err:
@@ -2551,7 +2558,4 @@ void sev_pci_exit(void)
 		return;
 
 	sev_firmware_shutdown(sev);
-
-	atomic_notifier_chain_unregister(&panic_notifier_list,
-					 &snp_panic_notifier);
 }
-- 
2.34.1