| 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
| ||
|
Message-ID: <20231016132819.1002933-18-michael.roth@amd.com>
Date: Mon, 16 Oct 2023 08:27:46 -0500
From: Michael Roth <michael.roth@....com>
To: <kvm@...r.kernel.org>
CC: <linux-coco@...ts.linux.dev>, <linux-mm@...ck.org>,
<linux-crypto@...r.kernel.org>, <x86@...nel.org>,
<linux-kernel@...r.kernel.org>, <tglx@...utronix.de>,
<mingo@...hat.com>, <jroedel@...e.de>, <thomas.lendacky@....com>,
<hpa@...or.com>, <ardb@...nel.org>, <pbonzini@...hat.com>,
<seanjc@...gle.com>, <vkuznets@...hat.com>, <jmattson@...gle.com>,
<luto@...nel.org>, <dave.hansen@...ux.intel.com>, <slp@...hat.com>,
<pgonda@...gle.com>, <peterz@...radead.org>,
<srinivas.pandruvada@...ux.intel.com>, <rientjes@...gle.com>,
<dovmurik@...ux.ibm.com>, <tobin@....com>, <bp@...en8.de>,
<vbabka@...e.cz>, <kirill@...temov.name>, <ak@...ux.intel.com>,
<tony.luck@...el.com>, <marcorr@...gle.com>,
<sathyanarayanan.kuppuswamy@...ux.intel.com>,
<alpergun@...gle.com>, <jarkko@...nel.org>, <ashish.kalra@....com>,
<nikunj.dadhania@....com>, <pankaj.gupta@....com>,
<liam.merwick@...cle.com>, <zhi.a.wang@...el.com>,
Brijesh Singh <brijesh.singh@....com>
Subject: [PATCH v10 17/50] crypto: ccp: Handle the legacy TMR allocation when SNP is enabled
From: Brijesh Singh <brijesh.singh@....com>
The behavior and requirement for the SEV-legacy command is altered when
the SNP firmware is in the INIT state. See SEV-SNP firmware specification
for more details.
Allocate the Trusted Memory Region (TMR) as a 2mb sized/aligned region
when SNP is enabled to satisfy new requirements for the SNP. Continue
allocating a 1mb region for !SNP configuration.
While at it, provide API that can be used by others to allocate a page
that can be used by the firmware. The immediate user for this API will
be the KVM driver. The KVM driver to need to allocate a firmware context
page during the guest creation. The context page need to be updated
by the firmware. See the SEV-SNP specification for further details.
Co-developed-by: Ashish Kalra <ashish.kalra@....com>
Signed-off-by: Ashish Kalra <ashish.kalra@....com>
Signed-off-by: Brijesh Singh <brijesh.singh@....com>
[mdr: use struct sev_data_snp_page_reclaim instead of passing paddr
directly to SEV_CMD_SNP_PAGE_RECLAIM]
Signed-off-by: Michael Roth <michael.roth@....com>
---
drivers/crypto/ccp/sev-dev.c | 151 ++++++++++++++++++++++++++++++++---
include/linux/psp-sev.h | 9 +++
2 files changed, 151 insertions(+), 9 deletions(-)
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 613b25f81498..ea21307a2b34 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -30,6 +30,7 @@
#include <asm/smp.h>
#include <asm/cacheflush.h>
#include <asm/e820/types.h>
+#include <asm/sev-host.h>
#include "psp-dev.h"
#include "sev-dev.h"
@@ -93,6 +94,13 @@ static void *sev_init_ex_buffer;
struct sev_data_range_list *snp_range_list;
static int __sev_snp_init_locked(int *error);
+/* When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB size. */
+#define SEV_SNP_ES_TMR_SIZE (2 * 1024 * 1024)
+
+static size_t sev_es_tmr_size = SEV_ES_TMR_SIZE;
+
+static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret);
+
static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
{
struct sev_device *sev = psp_master->sev_data;
@@ -193,11 +201,131 @@ static int sev_cmd_buffer_len(int cmd)
return 0;
}
+static int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked)
+{
+ /* Cbit maybe set in the paddr */
+ unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
+ int ret, err, i, n = 0;
+
+ for (i = 0; i < npages; i++, pfn++, n++) {
+ struct sev_data_snp_page_reclaim data = {0};
+
+ data.paddr = pfn << PAGE_SHIFT;
+
+ if (locked)
+ ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
+ else
+ ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err);
+
+ if (ret)
+ goto cleanup;
+
+ ret = rmp_make_shared(pfn, PG_LEVEL_4K);
+ if (ret)
+ goto cleanup;
+ }
+
+ return 0;
+
+cleanup:
+ /*
+ * If failed to reclaim the page then page is no longer safe to
+ * be release back to the system, leak it.
+ */
+ snp_leak_pages(pfn, npages - n);
+ return ret;
+}
+
+static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked)
+{
+ /* Cbit maybe set in the paddr */
+ unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT;
+ int rc, n = 0, i;
+
+ for (i = 0; i < npages; i++, n++, pfn++) {
+ rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true);
+ if (rc)
+ goto cleanup;
+ }
+
+ return 0;
+
+cleanup:
+ /*
+ * Try unrolling the firmware state changes by
+ * reclaiming the pages which were already changed to the
+ * firmware state.
+ */
+ snp_reclaim_pages(paddr, n, locked);
+
+ return rc;
+}
+
+static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked)
+{
+ unsigned long npages = 1ul << order, paddr;
+ struct sev_device *sev;
+ struct page *page;
+
+ if (!psp_master || !psp_master->sev_data)
+ return NULL;
+
+ page = alloc_pages(gfp_mask, order);
+ if (!page)
+ return NULL;
+
+ /* If SEV-SNP is initialized then add the page in RMP table. */
+ sev = psp_master->sev_data;
+ if (!sev->snp_initialized)
+ return page;
+
+ paddr = __pa((unsigned long)page_address(page));
+ if (rmp_mark_pages_firmware(paddr, npages, locked))
+ return NULL;
+
+ return page;
+}
+
+void *snp_alloc_firmware_page(gfp_t gfp_mask)
+{
+ struct page *page;
+
+ page = __snp_alloc_firmware_pages(gfp_mask, 0, false);
+
+ return page ? page_address(page) : NULL;
+}
+EXPORT_SYMBOL_GPL(snp_alloc_firmware_page);
+
+static void __snp_free_firmware_pages(struct page *page, int order, bool locked)
+{
+ struct sev_device *sev = psp_master->sev_data;
+ unsigned long paddr, npages = 1ul << order;
+
+ if (!page)
+ return;
+
+ paddr = __pa((unsigned long)page_address(page));
+ if (sev->snp_initialized &&
+ snp_reclaim_pages(paddr, npages, locked))
+ return;
+
+ __free_pages(page, order);
+}
+
+void snp_free_firmware_page(void *addr)
+{
+ if (!addr)
+ return;
+
+ __snp_free_firmware_pages(virt_to_page(addr), 0, false);
+}
+EXPORT_SYMBOL_GPL(snp_free_firmware_page);
+
static void *sev_fw_alloc(unsigned long len)
{
struct page *page;
- page = alloc_pages(GFP_KERNEL, get_order(len));
+ page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len), false);
if (!page)
return NULL;
@@ -443,7 +571,7 @@ static int __sev_init_locked(int *error)
data.tmr_address = __pa(sev_es_tmr);
data.flags |= SEV_INIT_FLAGS_SEV_ES;
- data.tmr_len = SEV_ES_TMR_SIZE;
+ data.tmr_len = sev_es_tmr_size;
}
return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
@@ -466,7 +594,7 @@ static int __sev_init_ex_locked(int *error)
data.tmr_address = __pa(sev_es_tmr);
data.flags |= SEV_INIT_FLAGS_SEV_ES;
- data.tmr_len = SEV_ES_TMR_SIZE;
+ data.tmr_len = sev_es_tmr_size;
}
return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
@@ -513,14 +641,16 @@ static int ___sev_platform_init_locked(int *error, bool probe)
if (!sev_es_tmr) {
/* Obtain the TMR memory area for SEV-ES use */
- sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
- if (sev_es_tmr)
+ sev_es_tmr = sev_fw_alloc(sev_es_tmr_size);
+ if (sev_es_tmr) {
/* Must flush the cache before giving it to the firmware */
- clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE);
- else
+ if (!sev->snp_initialized)
+ clflush_cache_range(sev_es_tmr, sev_es_tmr_size);
+ } else {
dev_warn(sev->dev,
"SEV: TMR allocation failed, SEV-ES support unavailable\n");
}
+ }
if (sev_init_ex_buffer) {
rc = sev_read_init_ex_file();
@@ -1030,6 +1160,8 @@ static int __sev_snp_init_locked(int *error)
sev->snp_initialized = true;
dev_dbg(sev->dev, "SEV-SNP firmware initialized\n");
+ sev_es_tmr_size = SEV_SNP_ES_TMR_SIZE;
+
return rc;
}
@@ -1536,8 +1668,9 @@ static void sev_firmware_shutdown(struct sev_device *sev)
/* The TMR area was encrypted, flush it from the cache */
wbinvd_on_all_cpus();
- free_pages((unsigned long)sev_es_tmr,
- get_order(SEV_ES_TMR_SIZE));
+ __snp_free_firmware_pages(virt_to_page(sev_es_tmr),
+ get_order(sev_es_tmr_size),
+ false);
sev_es_tmr = NULL;
}
diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index 61bb5849ebf2..9342cee1a1e6 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -898,6 +898,8 @@ int sev_guest_decommission(struct sev_data_decommission *data, int *error);
int sev_do_cmd(int cmd, void *data, int *psp_ret);
void *psp_copy_user_blob(u64 uaddr, u32 len);
+void *snp_alloc_firmware_page(gfp_t mask);
+void snp_free_firmware_page(void *addr);
#else /* !CONFIG_CRYPTO_DEV_SP_PSP */
@@ -925,6 +927,13 @@ sev_issue_cmd_external_user(struct file *filep, unsigned int id, void *data, int
static inline void *psp_copy_user_blob(u64 __user uaddr, u32 len) { return ERR_PTR(-EINVAL); }
+static inline void *snp_alloc_firmware_page(gfp_t mask)
+{
+ return NULL;
+}
+
+static inline void snp_free_firmware_page(void *addr) { }
+
#endif /* CONFIG_CRYPTO_DEV_SP_PSP */
#endif /* __PSP_SEV_H__ */
--
2.25.1
Powered by blists - more mailing lists