From patchwork Wed Sep 25 15:01:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 830537 Received: from mail-wm1-f73.google.com (mail-wm1-f73.google.com [209.85.128.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 110DB1917EB for ; Wed, 25 Sep 2024 15:02:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727276554; cv=none; b=rZ93EI341QSXcnua283Z2XY4p8/xkfQyVAVPaee21fWKL49y+9ZrYdMjSLK95YB+Ih2SUMqJbqWQMK/6P54fQwjiXmw0s4P5+m9A0+g+1l5ocshZnvn8soQUX9O//mRlQ0/w9mpJuIwdjyxPeK9mdE6kjTSp7dHhFieUyUbb7nE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727276554; c=relaxed/simple; bh=w/P+2/7/i0/j2dzTpIfGv0L554wt2D6+DkL221lAYlA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=hlde/89UvJ2hiV3qalgr7ILnWEzejlIFVrT0wgjx0vfpG3mjM43YGJS/lVE0PqOMfbpOFw6gszuPNGD1wmEj5gRfJheWCci0xIEEJX5jl17JNvLMseIHx4saDYBjUlo27FlxzPQnrm2qOqjuOKQbuuRMqdobkUu7ys/rzc4ALCc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=A6rF0mzg; arc=none smtp.client-ip=209.85.128.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="A6rF0mzg" Received: by mail-wm1-f73.google.com with SMTP id 5b1f17b1804b1-42cb374f0cdso5460505e9.0 for ; Wed, 25 Sep 2024 08:02:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1727276550; x=1727881350; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=vAC8l3Y8WvFUyajZb+pirsZCUpFvZ3r8+BwrpQuj/SE=; b=A6rF0mzgNO5k5xH80dgQj186dPnQGeeVqRHb+orNsMAT0mKVCvVjECgFsIle1N6xP2 ypjnsxssWW1e1kjkRgMWJak2mtDJty2lviQC2542ZJvNFLmZuTN+xmpbQhsO9uWHv1Ta +sZDu12TEmKoQRiRvIDyUWMuIGN0jpUGTprTdMQIO35g6lOi6uf4r34B3eiyp6Z8uZpz 0+mPvBXp+mo5wvs+AUIkM7xqZEmT7UfsE+ahovCiwiFefAM4l+bvzewa8OpTczEzKWTJ hQrVFsMw/dqKBz74Ih7+kqUMo30V7mIQzQOjeobfgXu+xeUrqiQbh2vm8j4jdZbHykud dGJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727276550; x=1727881350; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=vAC8l3Y8WvFUyajZb+pirsZCUpFvZ3r8+BwrpQuj/SE=; b=rktgIG2cXxmA6eMpAHMArj1qC+9VgdH12bEwWbYhjV2pk4PgJ7DUEKZLDzUmHE/lE+ Ytaaas+GmTw1yRd4GVTn05jhdTlsxkmILLbO6oHfFJl+8VhWUdtdbfB45UwQWc3ARu0u 6FKHMaKzQFq6NnzvaGKovUJHCtB6U1bIXpCcOlPg2sNhE4rw3j8JxI1s5ar9Dw27z+V3 vitlBYXOQiihiPFcQcNgP7Pl9XvIzoaRDsTcYJ162H18Zy57xX4xsNOcXPuJDnku5FD9 sDgshhnJNWp9sbva9/CaW1g6y+Pqvu2c5NxbEfGVUHzxJVF4+ZazIgUrJcbSRxHXp4Q5 wcfQ== X-Forwarded-Encrypted: i=1; AJvYcCWS2ZENuXfESDE+B3EryMN7IQpMMAA+/sDzlrbI/l9tJZTGO8qgWY/SziFYLPCzDgyV0BZizFNmpmI=@vger.kernel.org X-Gm-Message-State: AOJu0YwmFvqX3XbRbcfLxi/xNA3pNCi+XRChJ33cwZibPYm8lExlbXyr G0QQMgQPsgwRehJLh8icx/l8Sg8DFQaGhua7rvKr1hW3vAP2QHKf8vyY2I4MebF+jNLx1A== X-Google-Smtp-Source: AGHT+IGsHQZbBz7v7rjB2VogUNbzT3V2zpNGtAWZsXzYUPDihu4mWF0GF+yn2VIMs1ZNTkRqyJuf4PXN X-Received: from palermo.c.googlers.com ([fda3:e722:ac3:cc00:7b:198d:ac11:8138]) (user=ardb job=sendgmr) by 2002:a05:600c:4ca2:b0:42c:acd5:c641 with SMTP id 5b1f17b1804b1-42e96037975mr279665e9.2.1727276550412; Wed, 25 Sep 2024 08:02:30 -0700 (PDT) Date: Wed, 25 Sep 2024 17:01:16 +0200 In-Reply-To: <20240925150059.3955569-30-ardb+git@google.com> Precedence: bulk X-Mailing-List: linux-efi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240925150059.3955569-30-ardb+git@google.com> X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-Developer-Signature: v=1; a=openpgp-sha256; l=2723; i=ardb@kernel.org; h=from:subject; bh=tMElkct6gfSM6gp7MMWL/mRF1vGpc7RrYvn7ljZWXyE=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIe2L6iGZPaJMr8LDnd//b/RW8SszXOfdmXXq3NuftZV75 oQv+lfaUcrCIMbBICumyCIw+++7nacnStU6z5KFmcPKBDKEgYtTACZy4w/DHw7GS21Or9/PeKL6 7ZX8zCMs6WX7p7QFXu6zKz6oZDhn3S9GhnkFPcEfOSfJKv9IYrKOXfBu+/X/Xl4zqlnSnqz7v02 4kwsA X-Mailer: git-send-email 2.46.0.792.g87dc391469-goog Message-ID: <20240925150059.3955569-46-ardb+git@google.com> Subject: [RFC PATCH 16/28] x86/entry_64: Use RIP-relative addressing From: Ard Biesheuvel To: linux-kernel@vger.kernel.org Cc: Ard Biesheuvel , x86@kernel.org, "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Uros Bizjak , Dennis Zhou , Tejun Heo , Christoph Lameter , Mathieu Desnoyers , Paolo Bonzini , Vitaly Kuznetsov , Juergen Gross , Boris Ostrovsky , Greg Kroah-Hartman , Arnd Bergmann , Masahiro Yamada , Kees Cook , Nathan Chancellor , Keith Packard , Justin Stitt , Josh Poimboeuf , Arnaldo Carvalho de Melo , Namhyung Kim , Jiri Olsa , Ian Rogers , Adrian Hunter , Kan Liang , linux-doc@vger.kernel.org, linux-pm@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, linux-efi@vger.kernel.org, linux-arch@vger.kernel.org, linux-sparse@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-perf-users@vger.kernel.org, rust-for-linux@vger.kernel.org, llvm@lists.linux.dev From: Ard Biesheuvel Fix up a couple of occurrences in the x86_64 entry code where we take the absolute address of a symbol while we could use RIP-relative addressing just the same. This avoids relocation fixups at boot for these quantities. Signed-off-by: Ard Biesheuvel --- arch/x86/entry/calling.h | 9 +++++---- arch/x86/entry/entry_64.S | 12 +++++++----- 2 files changed, 12 insertions(+), 9 deletions(-) diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index ea81770629ee..099da5aaf929 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -375,8 +375,8 @@ For 32-bit we have the following conventions - kernel is built with .endm .macro SAVE_AND_SET_GSBASE scratch_reg:req save_reg:req + GET_PERCPU_BASE \scratch_reg \save_reg rdgsbase \save_reg - GET_PERCPU_BASE \scratch_reg wrgsbase \scratch_reg .endm @@ -412,15 +412,16 @@ For 32-bit we have the following conventions - kernel is built with * Thus the kernel would consume a guest's TSC_AUX if an NMI arrives * while running KVM's run loop. */ -.macro GET_PERCPU_BASE reg:req +.macro GET_PERCPU_BASE reg:req scratch:req LOAD_CPU_AND_NODE_SEG_LIMIT \reg andq $VDSO_CPUNODE_MASK, \reg - movq __per_cpu_offset(, \reg, 8), \reg + leaq __per_cpu_offset(%rip), \scratch + movq (\scratch, \reg, 8), \reg .endm #else -.macro GET_PERCPU_BASE reg:req +.macro GET_PERCPU_BASE reg:req scratch:req movq pcpu_unit_offsets(%rip), \reg .endm diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 1b5be07f8669..6509e12b6329 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1038,7 +1038,8 @@ SYM_CODE_START(error_entry) movl %ecx, %eax /* zero extend */ cmpq %rax, RIP+8(%rsp) je .Lbstep_iret - cmpq $.Lgs_change, RIP+8(%rsp) + leaq .Lgs_change(%rip), %rcx + cmpq %rcx, RIP+8(%rsp) jne .Lerror_entry_done_lfence /* @@ -1250,10 +1251,10 @@ SYM_CODE_START(asm_exc_nmi) * the outer NMI. */ - movq $repeat_nmi, %rdx + leaq repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja 1f - movq $end_repeat_nmi, %rdx + leaq end_repeat_nmi(%rip), %rdx cmpq 8(%rsp), %rdx ja nested_nmi_out 1: @@ -1307,7 +1308,8 @@ nested_nmi: pushq %rdx pushfq pushq $__KERNEL_CS - pushq $repeat_nmi + leaq repeat_nmi(%rip), %rdx + pushq %rdx /* Put stack back */ addq $(6*8), %rsp @@ -1346,7 +1348,7 @@ first_nmi: addq $8, (%rsp) /* Fix up RSP */ pushfq /* RFLAGS */ pushq $__KERNEL_CS /* CS */ - pushq $1f /* RIP */ + pushq 1f@GOTPCREL(%rip) /* RIP */ iretq /* continues at repeat_nmi below */ UNWIND_HINT_IRET_REGS 1: