From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 89EBB72 for ; Wed, 21 Jul 2021 14:20:49 +0000 (UTC) Received: from cap.home.8bytes.org (p4ff2b1ea.dip0.t-ipconnect.de [79.242.177.234]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id B8D259C2; Wed, 21 Jul 2021 16:20:28 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org, Eric Biederman Cc: kexec@lists.infradead.org, Joerg Roedel , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , Arvind Sankar , Joerg Roedel , linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH 06/12] x86/sev: Cache AP Jump Table Address Date: Wed, 21 Jul 2021 16:20:09 +0200 Message-Id: <20210721142015.1401-7-joro@8bytes.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210721142015.1401-1-joro@8bytes.org> References: <20210721142015.1401-1-joro@8bytes.org> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Joerg Roedel Store the physical address of the AP Jump Table in kernel memory so that it does not need to be fetched from the Hypervisor again. Signed-off-by: Joerg Roedel --- arch/x86/kernel/sev.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 5d3422e8b25e..eedba56b6bac 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -42,6 +42,9 @@ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE); */ static struct ghcb __initdata *boot_ghcb; +/* Cached AP Jump Table Address */ +static phys_addr_t sev_es_jump_table_pa; + /* #VC handler runtime per-CPU data */ struct sev_es_runtime_data { struct ghcb ghcb_page; @@ -546,12 +549,14 @@ void noinstr __sev_es_nmi_complete(void) __sev_put_ghcb(&state); } -static u64 get_jump_table_addr(void) +static phys_addr_t get_jump_table_addr(void) { struct ghcb_state state; unsigned long flags; struct ghcb *ghcb; - u64 ret = 0; + + if (sev_es_jump_table_pa) + return sev_es_jump_table_pa; local_irq_save(flags); @@ -567,39 +572,36 @@ static u64 get_jump_table_addr(void) if (ghcb_sw_exit_info_1_is_valid(ghcb) && ghcb_sw_exit_info_2_is_valid(ghcb)) - ret = ghcb->save.sw_exit_info_2; + sev_es_jump_table_pa = (phys_addr_t)ghcb->save.sw_exit_info_2; __sev_put_ghcb(&state); local_irq_restore(flags); - return ret; + return sev_es_jump_table_pa; } int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { u16 startup_cs, startup_ip; - phys_addr_t jump_table_pa; - u64 jump_table_addr; u16 __iomem *jump_table; + phys_addr_t pa; - jump_table_addr = get_jump_table_addr(); + pa = get_jump_table_addr(); /* On UP guests there is no jump table so this is not a failure */ - if (!jump_table_addr) + if (!pa) return 0; /* Check if AP Jump Table is page-aligned */ - if (jump_table_addr & ~PAGE_MASK) + if (pa & ~PAGE_MASK) return -EINVAL; - jump_table_pa = jump_table_addr & PAGE_MASK; - startup_cs = (u16)(rmh->trampoline_start >> 4); startup_ip = (u16)(rmh->sev_es_trampoline_start - rmh->trampoline_start); - jump_table = ioremap_encrypted(jump_table_pa, PAGE_SIZE); + jump_table = ioremap_encrypted(pa, PAGE_SIZE); if (!jump_table) return -EIO; -- 2.31.1