From: Joerg Roedel <joro@8bytes.org>
To: x86@kernel.org
Cc: Joerg Roedel <joro@8bytes.org>, Joerg Roedel <jroedel@suse.de>,
hpa@zytor.com, Andy Lutomirski <luto@kernel.org>,
Dave Hansen <dave.hansen@linux.intel.com>,
Peter Zijlstra <peterz@infradead.org>,
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>,
David Rientjes <rientjes@google.com>,
Cfir Cohen <cfir@google.com>, Erdem Aktas <erdemaktas@google.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Mike Stunes <mstunes@vmware.com>,
Sean Christopherson <sean.j.christopherson@intel.com>,
Martin Radev <martin.b.radev@gmail.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
virtualization@lists.linux-foundation.org
Subject: [PATCH v5 08/75] x86/umip: Factor out instruction decoding
Date: Fri, 24 Jul 2020 18:02:29 +0200 [thread overview]
Message-ID: <20200724160336.5435-9-joro@8bytes.org> (raw)
In-Reply-To: <20200724160336.5435-1-joro@8bytes.org>
From: Joerg Roedel <jroedel@suse.de>
Factor out the code used to decode an instruction with the correct
address and operand sizes to a helper function.
No functional changes.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/include/asm/insn-eval.h | 2 ++
arch/x86/kernel/umip.c | 23 +---------------
arch/x86/lib/insn-eval.c | 45 ++++++++++++++++++++++++++++++++
3 files changed, 48 insertions(+), 22 deletions(-)
diff --git a/arch/x86/include/asm/insn-eval.h b/arch/x86/include/asm/insn-eval.h
index b8b9ef1bbd06..392b4fe377f9 100644
--- a/arch/x86/include/asm/insn-eval.h
+++ b/arch/x86/include/asm/insn-eval.h
@@ -21,5 +21,7 @@ unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx);
int insn_get_code_seg_params(struct pt_regs *regs);
int insn_fetch_from_user(struct pt_regs *regs,
unsigned char buf[MAX_INSN_SIZE]);
+bool insn_decode(struct insn *insn, struct pt_regs *regs,
+ unsigned char buf[MAX_INSN_SIZE], int buf_size);
#endif /* _ASM_X86_INSN_EVAL_H */
diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c
index c9e5345da793..4d9044340e78 100644
--- a/arch/x86/kernel/umip.c
+++ b/arch/x86/kernel/umip.c
@@ -324,7 +324,6 @@ bool fixup_umip_exception(struct pt_regs *regs)
unsigned long *reg_addr;
void __user *uaddr;
struct insn insn;
- int seg_defs;
if (!regs)
return false;
@@ -339,27 +338,7 @@ bool fixup_umip_exception(struct pt_regs *regs)
if (!nr_copied)
return false;
- insn_init(&insn, buf, nr_copied, user_64bit_mode(regs));
-
- /*
- * Override the default operand and address sizes with what is specified
- * in the code segment descriptor. The instruction decoder only sets
- * the address size it to either 4 or 8 address bytes and does nothing
- * for the operand bytes. This OK for most of the cases, but we could
- * have special cases where, for instance, a 16-bit code segment
- * descriptor is used.
- * If there is an address override prefix, the instruction decoder
- * correctly updates these values, even for 16-bit defaults.
- */
- seg_defs = insn_get_code_seg_params(regs);
- if (seg_defs == -EINVAL)
- return false;
-
- insn.addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs);
- insn.opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs);
-
- insn_get_length(&insn);
- if (nr_copied < insn.length)
+ if (!insn_decode(&insn, regs, buf, nr_copied))
return false;
umip_inst = identify_insn(&insn);
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c
index 0c4f7ebc261b..f52046f90dd3 100644
--- a/arch/x86/lib/insn-eval.c
+++ b/arch/x86/lib/insn-eval.c
@@ -1407,3 +1407,48 @@ int insn_fetch_from_user(struct pt_regs *regs, unsigned char buf[MAX_INSN_SIZE])
return MAX_INSN_SIZE - not_copied;
}
+
+/**
+ * insn_decode() - Decode an instruction
+ * @insn: Structure to store decoded instruction
+ * @regs: Structure with register values as seen when entering kernel mode
+ * @buf: Buffer containing the instruction bytes
+ * @buf_size: Number of instruction bytes available in buf
+ *
+ * Decodes the instruction provided in buf and stores the decoding results in
+ * insn. Also determines the correct address and operand sizes.
+ *
+ * Returns:
+ *
+ * True if instruction was decoded, False otherwise.
+ */
+bool insn_decode(struct insn *insn, struct pt_regs *regs,
+ unsigned char buf[MAX_INSN_SIZE], int buf_size)
+{
+ int seg_defs;
+
+ insn_init(insn, buf, buf_size, user_64bit_mode(regs));
+
+ /*
+ * Override the default operand and address sizes with what is specified
+ * in the code segment descriptor. The instruction decoder only sets
+ * the address size it to either 4 or 8 address bytes and does nothing
+ * for the operand bytes. This OK for most of the cases, but we could
+ * have special cases where, for instance, a 16-bit code segment
+ * descriptor is used.
+ * If there is an address override prefix, the instruction decoder
+ * correctly updates these values, even for 16-bit defaults.
+ */
+ seg_defs = insn_get_code_seg_params(regs);
+ if (seg_defs == -EINVAL)
+ return false;
+
+ insn->addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs);
+ insn->opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs);
+
+ insn_get_length(insn);
+ if (buf_size < insn->length)
+ return false;
+
+ return true;
+}
--
2.27.0
next prev parent reply other threads:[~2020-07-24 16:11 UTC|newest]
Thread overview: 97+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-24 16:02 [PATCH v5 00/75] x86: SEV-ES Guest Support Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 01/75] KVM: SVM: Add GHCB definitions Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 02/75] KVM: SVM: Add GHCB Accessor functions Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 03/75] KVM: SVM: Use __packed shorthand Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 04/75] x86/cpufeatures: Add SEV-ES CPU feature Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 05/75] x86/traps: Move pf error codes to <asm/trap_pf.h> Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 06/75] x86/insn: Make inat-tables.c suitable for pre-decompression code Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 07/75] x86/umip: Factor out instruction fetch Joerg Roedel
2020-07-24 16:02 ` Joerg Roedel [this message]
2020-07-24 16:02 ` [PATCH v5 09/75] x86/insn: Add insn_get_modrm_reg_off() Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 10/75] x86/insn: Add insn_has_rep_prefix() helper Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 11/75] x86/boot/compressed/64: Disable red-zone usage Joerg Roedel
2020-07-24 17:43 ` Kees Cook
2020-07-24 17:58 ` Arvind Sankar
2020-07-24 16:02 ` [PATCH v5 12/75] x86/boot/compressed/64: Add IDT Infrastructure Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 13/75] x86/boot/compressed/64: Rename kaslr_64.c to ident_map_64.c Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 14/75] x86/boot/compressed/64: Add page-fault handler Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 15/75] x86/boot/compressed/64: Always switch to own page-table Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 16/75] x86/boot/compressed/64: Don't pre-map memory in KASLR code Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 17/75] x86/boot/compressed/64: Change add_identity_map() to take start and end Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 18/75] x86/boot/compressed/64: Add stage1 #VC handler Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 19/75] x86/boot/compressed/64: Call set_sev_encryption_mask earlier Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 20/75] x86/boot/compressed/64: Check return value of kernel_ident_mapping_init() Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 21/75] x86/boot/compressed/64: Add set_page_en/decrypted() helpers Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 22/75] x86/boot/compressed/64: Setup GHCB Based VC Exception handler Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 23/75] x86/boot/compressed/64: Unmap GHCB page before booting the kernel Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 24/75] x86/sev-es: Add support for handling IOIO exceptions Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 25/75] x86/fpu: Move xgetbv()/xsetbv() into separate header Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 26/75] x86/sev-es: Add CPUID handling to #VC handler Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 27/75] x86/idt: Move IDT to data segment Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 28/75] x86/idt: Split idt_data setup out of set_intr_gate() Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 29/75] x86/head/64: Install startup GDT Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 30/75] x86/head/64: Setup MSR_GS_BASE before calling into C code Joerg Roedel
2020-07-24 17:42 ` Kees Cook
2020-07-24 16:02 ` [PATCH v5 31/75] x86/head/64: Load GDT after switch to virtual addresses Joerg Roedel
2020-07-24 17:40 ` Kees Cook
2020-07-24 16:02 ` [PATCH v5 32/75] x86/head/64: Load segment registers earlier Joerg Roedel
2020-07-24 17:42 ` Kees Cook
2020-07-24 16:02 ` [PATCH v5 33/75] x86/head/64: Switch to initial stack earlier Joerg Roedel
2020-07-24 17:43 ` Kees Cook
2020-07-24 16:02 ` [PATCH v5 34/75] x86/head/64: Make fixup_pointer() static inline Joerg Roedel
2020-07-24 17:52 ` Kees Cook
2020-07-24 16:02 ` [PATCH v5 35/75] x86/head/64: Load IDT earlier Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 36/75] x86/head/64: Move early exception dispatch to C code Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 37/75] x86/head/64: Set CR4.FSGSBASE early Joerg Roedel
2020-07-24 16:02 ` [PATCH v5 38/75] x86/sev-es: Add SEV-ES Feature Detection Joerg Roedel
2020-07-24 17:54 ` Kees Cook
2020-07-24 16:03 ` [PATCH v5 39/75] x86/sev-es: Print SEV-ES info into kernel log Joerg Roedel
2020-07-24 17:54 ` Kees Cook
2020-07-24 16:03 ` [PATCH v5 40/75] x86/sev-es: Compile early handler code into kernel image Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 41/75] x86/sev-es: Setup early #VC handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 42/75] x86/sev-es: Setup GHCB based boot " Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 43/75] x86/sev-es: Setup per-cpu GHCBs for the runtime handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 44/75] x86/sev-es: Allocate and Map IST stack for #VC handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 45/75] x86/sev-es: Adjust #VC IST Stack on entering NMI handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 46/75] x86/dumpstack/64: Add noinstr version of get_stack_info() Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 47/75] x86/entry/64: Add entry code for #VC handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 48/75] x86/sev-es: Add Runtime #VC Exception Handler Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 49/75] x86/sev-es: Wire up existing #VC exit-code handlers Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 50/75] x86/sev-es: Handle instruction fetches from user-space Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 51/75] x86/sev-es: Handle MMIO events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 52/75] x86/sev-es: Handle MMIO String Instructions Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 53/75] x86/sev-es: Handle MSR events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 54/75] x86/sev-es: Handle DR7 read/write events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 55/75] x86/sev-es: Handle WBINVD Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 56/75] x86/sev-es: Handle RDTSC(P) Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 57/75] x86/sev-es: Handle RDPMC Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 58/75] x86/sev-es: Handle INVD Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 59/75] x86/sev-es: Handle MONITOR/MONITORX Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 60/75] x86/sev-es: Handle MWAIT/MWAITX Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 61/75] x86/sev-es: Handle VMMCALL Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 62/75] x86/sev-es: Handle #AC Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 63/75] x86/sev-es: Handle #DB Events Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 64/75] x86/paravirt: Allow hypervisor specific VMMCALL handling under SEV-ES Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 65/75] x86/kvm: Add KVM " Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 66/75] x86/vmware: Add VMware specific handling for VMMCALL " Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 67/75] x86/realmode: Add SEV-ES specific trampoline entry point Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 68/75] x86/realmode: Setup AP jump table Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 69/75] x86/smpboot: Setup TSS for starting AP Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 70/75] x86/head/64: Don't call verify_cpu() on starting APs Joerg Roedel
2020-07-24 17:57 ` Kees Cook
2020-07-24 16:03 ` [PATCH v5 71/75] x86/head/64: Rename start_cpu0 Joerg Roedel
2020-07-24 17:56 ` Kees Cook
2020-07-24 16:03 ` [PATCH v5 72/75] x86/sev-es: Support CPU offline/online Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 73/75] x86/sev-es: Handle NMI State Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 74/75] x86/efi: Add GHCB mappings when SEV-ES is active Joerg Roedel
2020-07-24 16:03 ` [PATCH v5 75/75] x86/sev-es: Check required CPU features for SEV-ES Joerg Roedel
2020-07-24 17:55 ` Kees Cook
2020-07-30 1:27 ` [PATCH v5 00/75] x86: SEV-ES Guest Support Mike Stunes
2020-07-30 12:26 ` Joerg Roedel
2020-07-30 23:23 ` Mike Stunes
2020-08-18 15:07 ` Joerg Roedel
2020-08-20 0:58 ` Mike Stunes
2020-08-20 12:10 ` Joerg Roedel
2020-08-21 8:05 ` Joerg Roedel
2020-08-21 17:42 ` Mike Stunes
2020-08-22 16:30 ` Joerg Roedel
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