Commit c3aa64ab authored by Tom Lendacky's avatar Tom Lendacky Committed by Borislav Petkov (AMD)
Browse files

crypto/ccp: Update HV_FIXED page states to allow freeing of memory 



After SNP is disabled, any pages allocated as HV_FIXED can now be freed.
Update the page state of these pages and the snp_leak_hv_fixed_pages()
function to free pages on SNP_SHUTDOWN.

Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarTycho Andersen (AMD) <tycho@kernel.org>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Acked-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Link: https://patch.msgid.link/20260324161301.1353976-8-tycho@kernel.org
parent f995fc37

drivers/crypto/ccp/sev-dev.c

+10 −3
Original line number Diff line number Diff line
@@ -1219,7 +1219,7 @@ static void snp_add_hv_fixed_pages(struct sev_device *sev, struct sev_data_range 


static void snp_leak_hv_fixed_pages(void)

{

	struct snp_hv_fixed_pages_entry *entry;

	struct snp_hv_fixed_pages_entry *entry, *nentry;



	/* List is protected by sev_cmd_mutex */

	lockdep_assert_held(&sev_cmd_mutex);
@@ -1227,10 +1227,16 @@ static void snp_leak_hv_fixed_pages(void) 
	if (list_empty(&snp_hv_fixed_pages))

		return;



	list_for_each_entry(entry, &snp_hv_fixed_pages, list)

		if (entry->page_state == HV_FIXED)

	list_for_each_entry_safe(entry, nentry, &snp_hv_fixed_pages, list) {

		if (entry->free && entry->page_state != HV_FIXED)

			__free_pages(entry->page, entry->order);

		else

			__snp_leak_pages(page_to_pfn(entry->page),

					 1 << entry->order, false);



		list_del(&entry->list);

		kfree(entry);

	}

}



bool sev_is_snp_ciphertext_hiding_supported(void)
@@ -2077,6 +2083,7 @@ static int __sev_snp_shutdown_locked(int *error, bool panic) 
	if (data.x86_snp_shutdown) {

		if (!panic)

			snp_shutdown();

		snp_hv_fixed_pages_state_update(sev, ALLOCATED);

	} else {

		/*

		 * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP