From: Joerg Roedel <joro@8bytes.org>
To: x86@kernel.org
Cc: hpa@zytor.com, Andy Lutomirski <luto@kernel.org>,
Dave Hansen <dave.hansen@linux.intel.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Hellstrom <thellstrom@vmware.com>,
Jiri Slaby <jslaby@suse.cz>,
Dan Williams <dan.j.williams@intel.com>,
Tom Lendacky <thomas.lendacky@amd.com>,
Juergen Gross <jgross@suse.com>,
Kees Cook <keescook@chromium.org>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
virtualization@lists.linux-foundation.org,
Joerg Roedel <joro@8bytes.org>, Joerg Roedel <jroedel@suse.de>
Subject: [PATCH 38/70] x86/sev-es: Setup early #VC handler
Date: Thu, 19 Mar 2020 10:13:35 +0100 [thread overview]
Message-ID: <20200319091407.1481-39-joro@8bytes.org> (raw)
In-Reply-To: <20200319091407.1481-1-joro@8bytes.org>
From: Joerg Roedel <jroedel@suse.de>
Setup an early handler for #VC exceptions. There is no GHCB mapped
yet, so just re-use the vc_no_ghcb_handler. It can only handle CPUID
exit-codes, but that should be enough to get the kernel through
verify_cpu() and __startup_64() until it runs on virtual addresses.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/include/asm/desc.h | 1 +
arch/x86/include/asm/processor.h | 1 +
arch/x86/include/asm/sev-es.h | 2 ++
arch/x86/kernel/head64.c | 17 +++++++++++++++
arch/x86/kernel/head_64.S | 36 ++++++++++++++++++++++++++++++++
arch/x86/kernel/idt.c | 10 +++++++++
6 files changed, 67 insertions(+)
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index 80bf63c08007..30e2a0e863b6 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -388,6 +388,7 @@ static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit)
void update_intr_gate(unsigned int n, const void *addr);
void alloc_intr_gate(unsigned int n, const void *addr);
+void set_early_idt_handler(gate_desc *idt, int n, void *handler);
static inline void init_idt_data(struct idt_data *data, unsigned int n,
const void *addr)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 09705ccc393c..4622427d01d4 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -768,6 +768,7 @@ extern int sysenter_setup(void);
/* Defined in head.S */
extern struct desc_ptr early_gdt_descr;
+extern struct desc_ptr early_idt_descr;
extern void switch_to_new_gdt(int);
extern void load_direct_gdt(int);
diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h
index 512d3ccb9832..caa29f75ce41 100644
--- a/arch/x86/include/asm/sev-es.h
+++ b/arch/x86/include/asm/sev-es.h
@@ -75,4 +75,6 @@ static inline u64 copy_lower_bits(u64 out, u64 in, unsigned int bits)
return out;
}
+extern void early_vc_handler(void);
+
#endif
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 8ccca109750d..b8613fc0a364 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -38,6 +38,7 @@
#include <asm/fixmap.h>
#include <asm/extable.h>
#include <asm/trap_defs.h>
+#include <asm/sev-es.h>
/*
* Manage page tables very early on.
@@ -515,3 +516,19 @@ void __head early_idt_setup_early_handler(unsigned long physaddr)
native_write_idt_entry(idt, i, &desc);
}
}
+
+void __head early_idt_setup(unsigned long physbase)
+{
+ gate_desc *idt = fixup_pointer(idt_table, physbase);
+ void __maybe_unused *handler;
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+ /* VMM Communication Exception */
+ handler = fixup_pointer(early_vc_handler, physbase);
+ set_early_idt_handler(idt, X86_TRAP_VC, handler);
+#endif
+
+ /* Initialize IDT descriptor and load IDT */
+ early_idt_descr.address = (unsigned long)idt;
+ native_load_idt(&early_idt_descr);
+}
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index bc0622a72d6d..b3acecdabd34 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -92,6 +92,12 @@ SYM_CODE_START_NOALIGN(startup_64)
.Lon_kernel_cs:
UNWIND_HINT_EMPTY
+ /* Setup IDT - Needed for SEV-ES */
+ leaq _text(%rip), %rdi
+ pushq %rsi
+ call early_idt_setup
+ popq %rsi
+
/* Sanitize CPU configuration */
call verify_cpu
@@ -370,6 +376,33 @@ SYM_CODE_START_LOCAL(early_idt_handler_common)
jmp restore_regs_and_return_to_kernel
SYM_CODE_END(early_idt_handler_common)
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+/*
+ * VC Exception handler used during very early boot. The
+ * early_idt_handler_array can't be used because it returns via the
+ * paravirtualized INTERRUPT_RETURN and pv-ops don't work that early.
+ */
+SYM_CODE_START_NOALIGN(early_vc_handler)
+ UNWIND_HINT_IRET_REGS offset=8
+
+ /* Build pt_regs */
+ PUSH_AND_CLEAR_REGS
+
+ /* Call C handler */
+ movq %rsp, %rdi
+ movq ORIG_RAX(%rsp), %rsi
+ call vc_no_ghcb_handler
+
+ /* Unwind pt_regs */
+ POP_REGS
+
+ /* Remove Error Code */
+ addq $8, %rsp
+
+ /* Pure iret required here - don't use INTERRUPT_RETURN */
+ iretq
+SYM_CODE_END(early_vc_handler)
+#endif
#define SYM_DATA_START_PAGE_ALIGNED(name) \
SYM_START(name, SYM_L_GLOBAL, .balign PAGE_SIZE)
@@ -511,6 +544,9 @@ SYM_DATA_END(level1_fixmap_pgt)
SYM_DATA(early_gdt_descr, .word GDT_ENTRIES*8-1)
SYM_DATA_LOCAL(early_gdt_descr_base, .quad INIT_PER_CPU_VAR(gdt_page))
+SYM_DATA(early_idt_descr, .word NUM_EXCEPTION_VECTORS * 16)
+SYM_DATA_LOCAL(early_idt_descr_base, .quad 0)
+
.align 16
/* This must match the first entry in level2_kernel_pgt */
SYM_DATA(phys_base, .quad 0x0)
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 4a2c7791c697..135d208a2d38 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -341,3 +341,13 @@ void alloc_intr_gate(unsigned int n, const void *addr)
if (!test_and_set_bit(n, system_vectors))
set_intr_gate(n, addr);
}
+
+void set_early_idt_handler(gate_desc *idt, int n, void *handler)
+{
+ struct idt_data data;
+ gate_desc desc;
+
+ init_idt_data(&data, n, handler);
+ idt_init_desc(&desc, &data);
+ native_write_idt_entry(idt, n, &desc);
+}
--
2.17.1
next prev parent reply other threads:[~2020-03-19 9:17 UTC|newest]
Thread overview: 181+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-19 9:12 [RFC PATCH 00/70 v2] x86: SEV-ES Guest Support Joerg Roedel
2020-03-19 9:12 ` [PATCH 01/70] KVM: SVM: Add GHCB definitions Joerg Roedel
2020-03-23 13:23 ` [PATCH] KVM: SVM: Use __packed shorthard Borislav Petkov
2020-03-24 12:43 ` Joerg Roedel
2020-03-19 9:12 ` [PATCH 02/70] KVM: SVM: Add GHCB Accessor functions Joerg Roedel
2020-03-19 9:13 ` [PATCH 03/70] x86/cpufeatures: Add SEV-ES CPU feature Joerg Roedel
2020-03-19 9:13 ` [PATCH 04/70] x86/traps: Move some definitions to <asm/trap_defs.h> Joerg Roedel
2020-03-19 9:13 ` [PATCH 05/70] x86/insn: Make inat-tables.c suitable for pre-decompression code Joerg Roedel
2020-03-25 15:39 ` Borislav Petkov
2020-03-27 3:02 ` Masami Hiramatsu
2020-04-16 15:24 ` Joerg Roedel
2020-04-17 12:50 ` Masami Hiramatsu
2020-04-17 13:39 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 06/70] x86/umip: Factor out instruction fetch Joerg Roedel
2020-03-26 17:21 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 07/70] x86/umip: Factor out instruction decoding Joerg Roedel
2020-03-26 17:24 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 08/70] x86/insn: Add insn_get_modrm_reg_off() Joerg Roedel
2020-03-27 3:57 ` Masami Hiramatsu
2020-03-19 9:13 ` [PATCH 09/70] x86/insn: Add insn_rep_prefix() helper Joerg Roedel
2020-03-27 3:56 ` Masami Hiramatsu
2020-03-19 9:13 ` [PATCH 10/70] x86/boot/compressed: Fix debug_puthex() parameter type Joerg Roedel
2020-03-28 11:23 ` [tip: x86/boot] " tip-bot2 for Joerg Roedel
2020-03-19 9:13 ` [PATCH 11/70] x86/boot/compressed/64: Disable red-zone usage Joerg Roedel
2020-03-31 13:16 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 12/70] x86/boot/compressed/64: Add IDT Infrastructure Joerg Roedel
2020-04-07 2:21 ` Arvind Sankar
2020-04-16 13:30 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 13/70] x86/boot/compressed/64: Rename kaslr_64.c to ident_map_64.c Joerg Roedel
2020-03-19 9:13 ` [PATCH 14/70] x86/boot/compressed/64: Add page-fault handler Joerg Roedel
2020-04-02 11:49 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 15/70] x86/boot/compressed/64: Always switch to own page-table Joerg Roedel
2020-04-06 11:56 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 16/70] x86/boot/compressed/64: Don't pre-map memory in KASLR code Joerg Roedel
2020-03-19 9:13 ` [PATCH 17/70] x86/boot/compressed/64: Change add_identity_map() to take start and end Joerg Roedel
2020-03-19 9:13 ` [PATCH 18/70] x86/boot/compressed/64: Add stage1 #VC handler Joerg Roedel
2020-03-20 21:16 ` David Rientjes
2020-03-20 22:19 ` Joerg Roedel
2020-04-06 12:41 ` Borislav Petkov
2020-03-19 9:13 ` [PATCH 19/70] x86/boot/compressed/64: Call set_sev_encryption_mask earlier Joerg Roedel
2020-03-19 9:13 ` [PATCH 20/70] x86/boot/compressed/64: Check return value of kernel_ident_mapping_init() Joerg Roedel
2020-03-19 9:13 ` [PATCH 21/70] x86/boot/compressed/64: Add function to map a page unencrypted Joerg Roedel
2020-03-20 20:53 ` David Rientjes
2020-03-20 21:02 ` Dave Hansen
2020-03-20 22:12 ` Joerg Roedel
2020-03-20 22:26 ` Dave Hansen
2020-03-21 15:40 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 22/70] x86/boot/compressed/64: Setup GHCB Based VC Exception handler Joerg Roedel
2020-03-19 9:13 ` [PATCH 23/70] x86/sev-es: Add support for handling IOIO exceptions Joerg Roedel
2020-03-20 21:03 ` David Rientjes
2020-03-20 22:24 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 24/70] x86/fpu: Move xgetbv()/xsetbv() into separate header Joerg Roedel
2020-03-19 9:13 ` [PATCH 25/70] x86/sev-es: Add CPUID handling to #VC handler Joerg Roedel
2020-03-19 9:13 ` [PATCH 26/70] x86/idt: Move IDT to data segment Joerg Roedel
2020-03-19 9:13 ` [PATCH 27/70] x86/idt: Split idt_data setup out of set_intr_gate() Joerg Roedel
2020-03-19 9:13 ` [PATCH 28/70] x86/idt: Move two function from k/idt.c to i/a/desc.h Joerg Roedel
2020-03-19 9:13 ` [PATCH 29/70] x86/head/64: Install boot GDT Joerg Roedel
2020-03-19 9:13 ` [PATCH 30/70] x86/head/64: Reload GDT after switch to virtual addresses Joerg Roedel
2020-03-19 9:13 ` [PATCH 31/70] x86/head/64: Load segment registers earlier Joerg Roedel
2020-03-19 9:13 ` [PATCH 32/70] x86/head/64: Switch to initial stack earlier Joerg Roedel
2020-03-19 9:13 ` [PATCH 33/70] x86/head/64: Build k/head64.c with -fno-stack-protector Joerg Roedel
2020-03-19 9:13 ` [PATCH 34/70] x86/head/64: Load IDT earlier Joerg Roedel
2020-03-19 9:13 ` [PATCH 35/70] x86/head/64: Move early exception dispatch to C code Joerg Roedel
2020-03-19 9:13 ` [PATCH 36/70] x86/sev-es: Add SEV-ES Feature Detection Joerg Roedel
2020-03-19 9:13 ` [PATCH 37/70] x86/sev-es: Compile early handler code into kernel image Joerg Roedel
2020-03-19 9:13 ` Joerg Roedel [this message]
2020-03-19 9:13 ` [PATCH 39/70] x86/sev-es: Setup GHCB based boot #VC handler Joerg Roedel
2020-03-19 9:13 ` [PATCH 40/70] x86/sev-es: Setup per-cpu GHCBs for the runtime handler Joerg Roedel
2020-04-14 19:03 ` Mike Stunes
2020-04-14 20:04 ` Tom Lendacky
2020-04-14 20:12 ` Dave Hansen
2020-04-14 20:16 ` Tom Lendacky
2020-04-14 20:18 ` Tom Lendacky
2020-04-15 15:54 ` Joerg Roedel
2020-04-15 15:53 ` Joerg Roedel
2020-04-23 1:33 ` Bo Gan
2020-04-23 11:30 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 41/70] x86/sev-es: Add Runtime #VC Exception Handler Joerg Roedel
2020-03-19 15:44 ` Andy Lutomirski
2020-03-19 16:24 ` Joerg Roedel
2020-03-19 18:43 ` Andy Lutomirski
2020-03-19 19:38 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 42/70] x86/sev-es: Support nested #VC exceptions Joerg Roedel
2020-03-19 15:46 ` Andy Lutomirski
2020-03-19 16:12 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 43/70] x86/sev-es: Wire up existing #VC exit-code handlers Joerg Roedel
2020-03-19 9:13 ` [PATCH 44/70] x86/sev-es: Handle instruction fetches from user-space Joerg Roedel
2020-03-19 9:13 ` [PATCH 45/70] x86/sev-es: Harden runtime #VC handler for exceptions " Joerg Roedel
2020-03-19 9:13 ` [PATCH 46/70] x86/sev-es: Filter exceptions not supported " Joerg Roedel
2020-03-19 9:13 ` [PATCH 47/70] x86/sev-es: Handle MMIO events Joerg Roedel
2020-03-19 9:13 ` [PATCH 48/70] x86/sev-es: Handle MMIO String Instructions Joerg Roedel
2020-03-19 9:13 ` [PATCH 49/70] x86/sev-es: Handle MSR events Joerg Roedel
2020-03-19 9:13 ` [PATCH 50/70] x86/sev-es: Handle DR7 read/write events Joerg Roedel
2020-03-19 9:13 ` [PATCH 51/70] x86/sev-es: Handle WBINVD Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 52/70] x86/sev-es: Handle RDTSC Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 53/70] x86/sev-es: Handle RDPMC Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 54/70] x86/sev-es: Handle INVD Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 55/70] x86/sev-es: Handle RDTSCP Events Joerg Roedel
2020-04-24 21:03 ` [PATCH] Allow RDTSC and RDTSCP from userspace Mike Stunes
2020-04-24 21:24 ` Dave Hansen
2020-04-24 21:27 ` Tom Lendacky
2020-04-24 22:53 ` Dave Hansen
2020-04-25 12:49 ` Joerg Roedel
2020-04-25 18:15 ` Andy Lutomirski
2020-04-25 19:10 ` Joerg Roedel
2020-04-25 19:47 ` Andy Lutomirski
2020-04-25 20:23 ` Joerg Roedel
2020-04-25 22:10 ` Andy Lutomirski
2020-04-27 17:37 ` Should SEV-ES #VC use IST? (Re: [PATCH] Allow RDTSC and RDTSCP from userspace) Andy Lutomirski
2020-04-27 18:15 ` Andrew Cooper
2020-04-27 18:43 ` Tom Lendacky
2020-04-28 7:55 ` Joerg Roedel
2020-04-28 16:34 ` Andrew Cooper
2020-06-23 11:07 ` Peter Zijlstra
2020-06-23 11:30 ` Joerg Roedel
2020-06-23 11:48 ` Peter Zijlstra
2020-06-23 12:04 ` Joerg Roedel
2020-06-23 12:52 ` Peter Zijlstra
2020-06-23 13:40 ` Joerg Roedel
2020-06-23 13:59 ` Peter Zijlstra
2020-06-23 14:53 ` Peter Zijlstra
2020-06-23 14:59 ` Joerg Roedel
2020-06-23 15:23 ` Peter Zijlstra
2020-06-23 15:38 ` Peter Zijlstra
2020-06-23 15:38 ` Joerg Roedel
2020-06-23 16:02 ` Peter Zijlstra
2020-06-23 15:39 ` Andrew Cooper
2020-06-23 15:52 ` Peter Zijlstra
2020-06-23 16:03 ` Dave Hansen
2020-06-23 16:13 ` Peter Zijlstra
2020-06-23 16:13 ` Borislav Petkov
2020-06-23 11:51 ` Andrew Cooper
2020-06-23 12:47 ` Peter Zijlstra
2020-06-23 13:57 ` Andrew Cooper
2020-06-23 15:51 ` Borislav Petkov
2020-06-23 9:45 ` Joerg Roedel
2020-06-23 10:45 ` Peter Zijlstra
2020-06-23 11:11 ` Joerg Roedel
2020-06-23 11:14 ` Peter Zijlstra
2020-06-23 11:43 ` Joerg Roedel
2020-06-23 11:50 ` Peter Zijlstra
2020-06-23 12:12 ` Joerg Roedel
2020-06-23 13:03 ` Peter Zijlstra
2020-06-23 14:49 ` Joerg Roedel
2020-06-23 15:16 ` Peter Zijlstra
2020-06-23 15:32 ` Andrew Cooper
2020-06-23 16:10 ` Borislav Petkov
2020-06-23 15:22 ` Andrew Cooper
2020-06-23 18:26 ` Andy Lutomirski
2020-06-23 18:56 ` Andrew Cooper
2020-04-27 18:47 ` [PATCH] Allow RDTSC and RDTSCP from userspace Dave Hansen
2020-04-25 12:28 ` Joerg Roedel
2020-03-19 9:13 ` [PATCH 56/70] x86/sev-es: Handle MONITOR/MONITORX Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 57/70] x86/sev-es: Handle MWAIT/MWAITX Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 58/70] x86/sev-es: Handle VMMCALL Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 59/70] x86/sev-es: Handle #AC Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 60/70] x86/sev-es: Handle #DB Events Joerg Roedel
2020-03-19 9:13 ` [PATCH 61/70] x86/paravirt: Allow hypervisor specific VMMCALL handling under SEV-ES Joerg Roedel
2020-03-19 9:13 ` [PATCH 62/70] x86/kvm: Add KVM " Joerg Roedel
2020-03-20 21:23 ` David Rientjes
2020-03-20 22:21 ` Joerg Roedel
2020-03-19 9:14 ` [PATCH 63/70] x86/vmware: Add VMware specific handling for VMMCALL " Joerg Roedel
2020-03-19 10:18 ` Thomas Hellstrom
2020-03-19 9:14 ` [PATCH 64/70] x86/realmode: Add SEV-ES specific trampoline entry point Joerg Roedel
2020-03-19 9:14 ` [PATCH 65/70] x86/realmode: Setup AP jump table Joerg Roedel
2020-03-19 9:14 ` [PATCH 66/70] x86/head/64: Don't call verify_cpu() on starting APs Joerg Roedel
2020-03-19 9:14 ` [PATCH 67/70] x86/head/64: Rename start_cpu0 Joerg Roedel
2020-03-19 9:14 ` [PATCH 68/70] x86/sev-es: Support CPU offline/online Joerg Roedel
2020-03-19 9:14 ` [PATCH 69/70] x86/cpufeature: Add SEV_ES_GUEST CPU Feature Joerg Roedel
2020-03-19 9:14 ` [PATCH 70/70] x86/sev-es: Add NMI state tracking Joerg Roedel
2020-03-19 15:35 ` Andy Lutomirski
2020-03-19 16:07 ` Joerg Roedel
2020-03-19 18:40 ` Andy Lutomirski
2020-03-19 19:26 ` Joerg Roedel
2020-03-19 21:27 ` Andy Lutomirski
2020-03-20 19:48 ` Joerg Roedel
2020-03-20 13:17 ` [RFC PATCH v2.1] x86/sev-es: Handle NMI State Joerg Roedel
2020-03-20 14:42 ` Dave Hansen
2020-03-20 19:42 ` Joerg Roedel
2020-03-19 16:53 ` [PATCH 70/70] x86/sev-es: Add NMI state tracking Mika Penttilä
2020-03-19 19:41 ` Joerg Roedel
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