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[46.102.197.194]) by smtp.gmail.com with ESMTPSA id ll9-20020a170907190900b00a42e4b5ab00sm2379645ejc.41.2024.02.26.04.55.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 26 Feb 2024 04:55:04 -0800 (PST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 430a8b83-d4a6-11ee-98f5-efadbce2ee36 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1708952104; x=1709556904; darn=lists.xenproject.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iwdL6fju3yL7qCFHqrnxqIG6VGZd2rsCO2B5E1ELuco=; b=FPXCLop5y5Fmug6EbeIqryKW/Hwk+uVDYAeSGE2Z5XAEsg6ni+Jdq3zMAHUv2UXqDf 5g7rJ+j8PvxD+io7l2r32Y6bG0Q+GD0sks2HXvEbPaWK8ccT0yTnuEw4S3XoOnYocv0n FiKSZxDDtPMBL38gR3P+ebg5TBygJ4R80yVFg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1708952104; x=1709556904; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iwdL6fju3yL7qCFHqrnxqIG6VGZd2rsCO2B5E1ELuco=; b=OuEzg6hUpp8eDrSfnltJcr6oy5cq3GDWCgIO5dn+Kfw8KCFjIMAnOK6AGzgC6/hmDH DXvmhuzt62Js1lvwTIsoXiP0zPYKdAL8Sxt6qfHcHMzl5xt7Z5b905hpOYJ9PKqQEJcH 29DDOx1UtU7WndN1Q12YoaEhiwuSl7OK0TAcisy82S77iKUvn+0KYu2MPDY/q/hU52mp a1dYLFdKrZnKBWqAefxdtW5sBqhluNX8m0phkr1OF+P2Iobh4uRuzGbfjH0jJ/kp0n5i 7KNiP0+XlOO74JDqijV3NnKTrMC2R7Coget9XqEBT537C0nurPA9T0NHGJe/kiySMO+D lsjQ== X-Gm-Message-State: AOJu0Ywohu4KyGCYDFFkiLYCj3Ce6E87uYPkJbj/0nnNewhKaHQUtFs6 21dSPKTETW1MkG96a49MN6/gwjJnt1iT56TuWkUUMk9tcvzWmhLaFYtN4WYyEJE1DLzhcMNmBG3 S X-Google-Smtp-Source: AGHT+IEiO4/3u92iuWSWX1XLK6tyUrg8vJ3vqcOHRIZXVtosNyOvF+7YKfdvK7IrnDxa4yULQuLlIg== X-Received: by 2002:a17:906:57d3:b0:a43:239c:3d0d with SMTP id u19-20020a17090657d300b00a43239c3d0dmr2556694ejr.37.1708952104635; Mon, 26 Feb 2024 04:55:04 -0800 (PST) From: Andrew Cooper To: Xen-devel Cc: Andrew Cooper , Jan Beulich , =?utf-8?q?Roger_Pau_Monn=C3=A9?= , Wei Liu Subject: [PATCH 3/3] x86/entry: Introduce EFRAME_* constants Date: Mon, 26 Feb 2024 12:55:01 +0000 Message-Id: <20240226125501.1233599-4-andrew.cooper3@citrix.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20240226125501.1233599-1-andrew.cooper3@citrix.com> References: <20240226125501.1233599-1-andrew.cooper3@citrix.com> MIME-Version: 1.0 restore_all_guest() does a lot of manipulation of the stack after popping the GPRs, and uses raw %rsp displacements to do so. Also, almost all entrypaths use raw %rsp displacements prior to pushing GPRs. Provide better mnemonics, to aid readability and reduce the chance of errors when editing. No functional change. The resulting binary is identical. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich --- CC: Jan Beulich CC: Roger Pau Monné CC: Wei Liu --- xen/arch/x86/x86_64/asm-offsets.c | 17 ++++++++ xen/arch/x86/x86_64/compat/entry.S | 2 +- xen/arch/x86/x86_64/entry.S | 68 +++++++++++++++--------------- 3 files changed, 52 insertions(+), 35 deletions(-) diff --git a/xen/arch/x86/x86_64/asm-offsets.c b/xen/arch/x86/x86_64/asm-offsets.c index fee0edc61abb..4cc23cd032c1 100644 --- a/xen/arch/x86/x86_64/asm-offsets.c +++ b/xen/arch/x86/x86_64/asm-offsets.c @@ -51,6 +51,23 @@ void __dummy__(void) OFFSET(UREGS_kernel_sizeof, struct cpu_user_regs, es); BLANK(); + /* + * EFRAME_* is for the entry/exit logic where %rsp is pointing at + * UREGS_error_code and GPRs are still guest values. + */ +#define OFFSET_EF(sym, mem) \ + DEFINE(sym, offsetof(struct cpu_user_regs, mem) - \ + offsetof(struct cpu_user_regs, error_code)) + + OFFSET_EF(EFRAME_entry_vector, entry_vector); + OFFSET_EF(EFRAME_rip, rip); + OFFSET_EF(EFRAME_cs, cs); + OFFSET_EF(EFRAME_eflags, eflags); + OFFSET_EF(EFRAME_rsp, rsp); + BLANK(); + +#undef OFFSET_EF + OFFSET(VCPU_processor, struct vcpu, processor); OFFSET(VCPU_domain, struct vcpu, domain); OFFSET(VCPU_vcpu_info, struct vcpu, vcpu_info_area.map); diff --git a/xen/arch/x86/x86_64/compat/entry.S b/xen/arch/x86/x86_64/compat/entry.S index 727ab65290de..2f8fe5ebfbe4 100644 --- a/xen/arch/x86/x86_64/compat/entry.S +++ b/xen/arch/x86/x86_64/compat/entry.S @@ -15,7 +15,7 @@ FUNC(entry_int82) ENDBR64 ALTERNATIVE "", clac, X86_FEATURE_XEN_SMAP pushq $0 - movb $HYPERCALL_VECTOR, 4(%rsp) + movb $HYPERCALL_VECTOR, EFRAME_entry_vector(%rsp) SAVE_ALL compat=1 /* DPL1 gate, restricted to 32bit PV guests only. */ SPEC_CTRL_ENTRY_FROM_PV /* Req: %rsp=regs/cpuinfo, %rdx=0, Clob: acd */ diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S index f8938b0b42fd..1b846f3aaff0 100644 --- a/xen/arch/x86/x86_64/entry.S +++ b/xen/arch/x86/x86_64/entry.S @@ -188,15 +188,15 @@ FUNC_LOCAL(restore_all_guest) RESTORE_ALL BUILD_BUG_ON(TRAP_syscall & 0xff) - testb $TRAP_syscall >> 8, 4+1(%rsp) + testb $TRAP_syscall >> 8, EFRAME_entry_vector + 1(%rsp) jz iret_exit_to_guest - movq 24(%rsp),%r11 # RFLAGS + mov EFRAME_eflags(%rsp), %r11 andq $~(X86_EFLAGS_IOPL | X86_EFLAGS_VM), %r11 orq $X86_EFLAGS_IF,%r11 /* Don't use SYSRET path if the return address is not canonical. */ - movq 8(%rsp),%rcx + mov EFRAME_rip(%rsp), %rcx sarq $47,%rcx incl %ecx cmpl $1,%ecx @@ -211,19 +211,19 @@ FUNC_LOCAL(restore_all_guest) ALTERNATIVE "", rag_clrssbsy, X86_FEATURE_XEN_SHSTK #endif - movq 8(%rsp), %rcx # RIP - cmpw $FLAT_USER_CS32,16(%rsp)# CS - movq 32(%rsp),%rsp # RSP + mov EFRAME_rip(%rsp), %rcx + cmpw $FLAT_USER_CS32, EFRAME_cs(%rsp) + mov EFRAME_rsp(%rsp), %rsp je 1f sysretq 1: sysretl LABEL_LOCAL(.Lrestore_rcx_iret_exit_to_guest) - movq 8(%rsp), %rcx # RIP + mov EFRAME_rip(%rsp), %rcx /* No special register assumptions. */ iret_exit_to_guest: - andl $~(X86_EFLAGS_IOPL | X86_EFLAGS_VM), 24(%rsp) - orl $X86_EFLAGS_IF,24(%rsp) + andl $~(X86_EFLAGS_IOPL | X86_EFLAGS_VM), EFRAME_eflags(%rsp) + orl $X86_EFLAGS_IF, EFRAME_eflags(%rsp) addq $8,%rsp .Lft0: iretq _ASM_PRE_EXTABLE(.Lft0, handle_exception) @@ -256,7 +256,7 @@ FUNC(lstar_enter) pushq %rcx pushq $0 BUILD_BUG_ON(TRAP_syscall & 0xff) - movb $TRAP_syscall >> 8, 4+1(%rsp) + movb $TRAP_syscall >> 8, EFRAME_entry_vector + 1(%rsp) SAVE_ALL SPEC_CTRL_ENTRY_FROM_PV /* Req: %rsp=regs/cpuinfo, %rdx=0, Clob: acd */ @@ -295,7 +295,7 @@ FUNC(cstar_enter) pushq %rcx pushq $0 BUILD_BUG_ON(TRAP_syscall & 0xff) - movb $TRAP_syscall >> 8, 4+1(%rsp) + movb $TRAP_syscall >> 8, EFRAME_entry_vector + 1(%rsp) SAVE_ALL SPEC_CTRL_ENTRY_FROM_PV /* Req: %rsp=regs/cpuinfo, %rdx=0, Clob: acd */ @@ -338,7 +338,7 @@ LABEL(sysenter_eflags_saved, 0) pushq $0 /* null rip */ pushq $0 BUILD_BUG_ON(TRAP_syscall & 0xff) - movb $TRAP_syscall >> 8, 4+1(%rsp) + movb $TRAP_syscall >> 8, EFRAME_entry_vector + 1(%rsp) SAVE_ALL SPEC_CTRL_ENTRY_FROM_PV /* Req: %rsp=regs/cpuinfo, %rdx=0, Clob: acd */ @@ -393,7 +393,7 @@ FUNC(entry_int80) ENDBR64 ALTERNATIVE "", clac, X86_FEATURE_XEN_SMAP pushq $0 - movb $0x80, 4(%rsp) + movb $0x80, EFRAME_entry_vector(%rsp) SAVE_ALL SPEC_CTRL_ENTRY_FROM_PV /* Req: %rsp=regs/cpuinfo, %rdx=0, Clob: acd */ @@ -658,7 +658,7 @@ END(ret_from_intr) .section .init.text, "ax", @progbits FUNC(early_page_fault) ENDBR64 - movb $X86_EXC_PF, 4(%rsp) + movb $X86_EXC_PF, EFRAME_entry_vector(%rsp) SAVE_ALL movq %rsp, %rdi call do_early_page_fault @@ -727,7 +727,7 @@ END(common_interrupt) FUNC(entry_PF) ENDBR64 - movb $X86_EXC_PF, 4(%rsp) + movb $X86_EXC_PF, EFRAME_entry_vector(%rsp) END(entry_PF) /* No special register assumptions. */ FUNC(handle_exception, 0) @@ -911,98 +911,98 @@ END(entry_DE) FUNC(entry_MF) ENDBR64 pushq $0 - movb $X86_EXC_MF, 4(%rsp) + movb $X86_EXC_MF, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_MF) FUNC(entry_XM) ENDBR64 pushq $0 - movb $X86_EXC_XM, 4(%rsp) + movb $X86_EXC_XM, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_XM) FUNC(entry_NM) ENDBR64 pushq $0 - movb $X86_EXC_NM, 4(%rsp) + movb $X86_EXC_NM, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_NM) FUNC(entry_DB) ENDBR64 pushq $0 - movb $X86_EXC_DB, 4(%rsp) + movb $X86_EXC_DB, EFRAME_entry_vector(%rsp) jmp handle_ist_exception END(entry_DB) FUNC(entry_BP) ENDBR64 pushq $0 - movb $X86_EXC_BP, 4(%rsp) + movb $X86_EXC_BP, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_BP) FUNC(entry_OF) ENDBR64 pushq $0 - movb $X86_EXC_OF, 4(%rsp) + movb $X86_EXC_OF, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_OF) FUNC(entry_BR) ENDBR64 pushq $0 - movb $X86_EXC_BR, 4(%rsp) + movb $X86_EXC_BR, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_BR) FUNC(entry_UD) ENDBR64 pushq $0 - movb $X86_EXC_UD, 4(%rsp) + movb $X86_EXC_UD, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_UD) FUNC(entry_TS) ENDBR64 - movb $X86_EXC_TS, 4(%rsp) + movb $X86_EXC_TS, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_TS) FUNC(entry_NP) ENDBR64 - movb $X86_EXC_NP, 4(%rsp) + movb $X86_EXC_NP, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_NP) FUNC(entry_SS) ENDBR64 - movb $X86_EXC_SS, 4(%rsp) + movb $X86_EXC_SS, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_SS) FUNC(entry_GP) ENDBR64 - movb $X86_EXC_GP, 4(%rsp) + movb $X86_EXC_GP, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_GP) FUNC(entry_AC) ENDBR64 - movb $X86_EXC_AC, 4(%rsp) + movb $X86_EXC_AC, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_AC) FUNC(entry_CP) ENDBR64 - movb $X86_EXC_CP, 4(%rsp) + movb $X86_EXC_CP, EFRAME_entry_vector(%rsp) jmp handle_exception END(entry_CP) FUNC(entry_DF) ENDBR64 - movb $X86_EXC_DF, 4(%rsp) + movb $X86_EXC_DF, EFRAME_entry_vector(%rsp) /* Set AC to reduce chance of further SMAP faults */ ALTERNATIVE "", stac, X86_FEATURE_XEN_SMAP SAVE_ALL @@ -1028,7 +1028,7 @@ END(entry_DF) FUNC(entry_NMI) ENDBR64 pushq $0 - movb $X86_EXC_NMI, 4(%rsp) + movb $X86_EXC_NMI, EFRAME_entry_vector(%rsp) END(entry_NMI) FUNC(handle_ist_exception) @@ -1164,7 +1164,7 @@ END(handle_ist_exception) FUNC(entry_MC) ENDBR64 pushq $0 - movb $X86_EXC_MC, 4(%rsp) + movb $X86_EXC_MC, EFRAME_entry_vector(%rsp) jmp handle_ist_exception END(entry_MC) @@ -1203,7 +1203,7 @@ FUNC_LOCAL(autogen_stubs, 0) /* Automatically generated stubs. */ 1: ENDBR64 pushq $0 - movb $vec,4(%rsp) + movb $vec, EFRAME_entry_vector(%rsp) jmp common_interrupt entrypoint 1b @@ -1217,7 +1217,7 @@ FUNC_LOCAL(autogen_stubs, 0) /* Automatically generated stubs. */ test $8,%spl /* 64bit exception frames are 16 byte aligned, but the word */ jz 2f /* size is 8 bytes. Check whether the processor gave us an */ pushq $0 /* error code, and insert an empty one if not. */ -2: movb $vec,4(%rsp) +2: movb $vec, EFRAME_entry_vector(%rsp) jmp handle_exception entrypoint 1b