linux-doc.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Anup Patel <anup.patel@wdc.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>,
	Palmer Dabbelt <palmerdabbelt@google.com>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Alexander Graf <graf@amazon.com>,
	Atish Patra <atish.patra@wdc.com>,
	Alistair Francis <Alistair.Francis@wdc.com>,
	Damien Le Moal <damien.lemoal@wdc.com>,
	Anup Patel <anup@brainfault.org>,
	kvm@vger.kernel.org, kvm-riscv@lists.infradead.org,
	linux-riscv@lists.infradead.org, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev
Subject: Re: [PATCH v18 14/18] RISC-V: KVM: Implement ONE REG interface for FP registers
Date: Thu, 20 May 2021 09:09:24 +0300	[thread overview]
Message-ID: <20210520060924.GD1955@kadam> (raw)
In-Reply-To: <20210519033553.1110536-15-anup.patel@wdc.com>

On Wed, May 19, 2021 at 09:05:49AM +0530, Anup Patel wrote:
> +static int kvm_riscv_vcpu_set_reg_fp(struct kvm_vcpu *vcpu,
> +				     const struct kvm_one_reg *reg,
> +				     unsigned long rtype)
> +{
> +	struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
> +	unsigned long isa = vcpu->arch.isa;
> +	unsigned long __user *uaddr =
> +			(unsigned long __user *)(unsigned long)reg->addr;
> +	unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK |
> +					    KVM_REG_SIZE_MASK |
> +					    rtype);
> +	void *reg_val;
> +
> +	if ((rtype == KVM_REG_RISCV_FP_F) &&
> +	    riscv_isa_extension_available(&isa, f)) {
> +		if (KVM_REG_SIZE(reg->id) != sizeof(u32))
> +			return -EINVAL;
> +		if (reg_num == KVM_REG_RISCV_FP_F_REG(fcsr))
> +			reg_val = &cntx->fp.f.fcsr;
> +		else if ((KVM_REG_RISCV_FP_F_REG(f[0]) <= reg_num) &&
> +			  reg_num <= KVM_REG_RISCV_FP_F_REG(f[31]))
> +			reg_val = &cntx->fp.f.f[reg_num];
> +		else
> +			return -EINVAL;
> +	} else if ((rtype == KVM_REG_RISCV_FP_D) &&
> +		   riscv_isa_extension_available(&isa, d)) {
> +		if (reg_num == KVM_REG_RISCV_FP_D_REG(fcsr)) {
> +			if (KVM_REG_SIZE(reg->id) != sizeof(u32))
> +				return -EINVAL;
> +			reg_val = &cntx->fp.d.fcsr;
> +		} else if ((KVM_REG_RISCV_FP_D_REG(f[0]) <= reg_num) &&
> +			   reg_num <= KVM_REG_RISCV_FP_D_REG(f[31])) {
> +			if (KVM_REG_SIZE(reg->id) != sizeof(u64))
> +				return -EINVAL;
> +			reg_val = &cntx->fp.d.f[reg_num];
> +		} else
> +			return -EINVAL;
> +	} else
> +		return -EINVAL;
> +
> +	if (copy_from_user(reg_val, uaddr, KVM_REG_SIZE(reg->id)))
                           ^^^^^^^
It sort of bothers me that if this copy fails then we have no idea
what garbage is in reg_val.  It would be nicer to copy it to a temporary
buffer and then memcpy it when we know it's going succeed.

> +		return -EFAULT;
> +
> +	return 0;
> +}

regards,
dan carpenter

  parent reply	other threads:[~2021-05-20  6:10 UTC|newest]

Thread overview: 47+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-19  3:35 [PATCH v18 00/18] KVM RISC-V Support Anup Patel
2021-05-19  3:35 ` [PATCH v18 01/18] RISC-V: Add hypervisor extension related CSR defines Anup Patel
2021-05-19  3:35 ` [PATCH v18 02/18] RISC-V: Add initial skeletal KVM support Anup Patel
2021-05-19  9:24   ` Dan Carpenter
2021-05-19 10:17   ` Dan Carpenter
2021-05-19  3:35 ` [PATCH v18 03/18] RISC-V: KVM: Implement VCPU create, init and destroy functions Anup Patel
2021-05-19  3:35 ` [PATCH v18 04/18] RISC-V: KVM: Implement VCPU interrupts and requests handling Anup Patel
2021-05-19  3:35 ` [PATCH v18 05/18] RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls Anup Patel
2021-05-19  3:35 ` [PATCH v18 06/18] RISC-V: KVM: Implement VCPU world-switch Anup Patel
2021-05-19  3:35 ` [PATCH v18 07/18] RISC-V: KVM: Handle MMIO exits for VCPU Anup Patel
2021-05-19  3:35 ` [PATCH v18 08/18] RISC-V: KVM: Handle WFI " Anup Patel
2021-05-19  3:35 ` [PATCH v18 09/18] RISC-V: KVM: Implement VMID allocator Anup Patel
2021-05-19  3:35 ` [PATCH v18 10/18] RISC-V: KVM: Implement stage2 page table programming Anup Patel
2021-05-19  3:35 ` [PATCH v18 11/18] RISC-V: KVM: Implement MMU notifiers Anup Patel
2021-05-19 10:09   ` Dan Carpenter
2021-05-19  3:35 ` [PATCH v18 12/18] RISC-V: KVM: Add timer functionality Anup Patel
2021-05-19  3:35 ` [PATCH v18 13/18] RISC-V: KVM: FP lazy save/restore Anup Patel
2021-05-19  3:35 ` [PATCH v18 14/18] RISC-V: KVM: Implement ONE REG interface for FP registers Anup Patel
2021-05-19 10:11   ` Dan Carpenter
2021-05-20  6:09   ` Dan Carpenter [this message]
2021-05-19  3:35 ` [PATCH v18 15/18] RISC-V: KVM: Add SBI v0.1 support Anup Patel
2021-05-19  3:35 ` [PATCH v18 16/18] RISC-V: KVM: Document RISC-V specific parts of KVM API Anup Patel
2021-05-19  3:35 ` [PATCH v18 17/18] RISC-V: KVM: Move sources to drivers/staging directory Anup Patel
2021-05-19  3:35 ` [PATCH v18 18/18] RISC-V: KVM: Add MAINTAINERS entry Anup Patel
2021-05-19  4:58 ` [PATCH v18 00/18] KVM RISC-V Support Greg Kroah-Hartman
2021-05-19  5:10   ` Anup Patel
2021-05-19  5:21     ` Greg Kroah-Hartman
2021-05-19 10:47       ` Greg Kroah-Hartman
2021-05-19 11:18         ` Paolo Bonzini
2021-05-19 12:23           ` Greg Kroah-Hartman
2021-05-19 13:29             ` Paolo Bonzini
2021-05-19 13:58               ` Greg Kroah-Hartman
2021-05-19 15:08                 ` Dan Carpenter
2021-05-19 15:26                   ` Paolo Bonzini
2021-05-21 17:13                 ` Palmer Dabbelt
2021-05-21 17:21                   ` Paolo Bonzini
2021-05-21 17:47                     ` Greg KH
2021-05-21 18:08                       ` Palmer Dabbelt
2021-05-21 18:25                         ` Greg KH
2021-05-21 20:25                       ` Paolo Bonzini
2021-05-24  7:09 ` Guo Ren
2021-05-24 22:57   ` Palmer Dabbelt
2021-05-24 23:08     ` Damien Le Moal
2021-05-25  7:37       ` Greg KH
2021-05-25  8:01         ` Damien Le Moal
2021-05-25  8:11           ` Greg KH
2021-05-25  8:24             ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210520060924.GD1955@kadam \
    --to=dan.carpenter@oracle.com \
    --cc=Alistair.Francis@wdc.com \
    --cc=anup.patel@wdc.com \
    --cc=anup@brainfault.org \
    --cc=aou@eecs.berkeley.edu \
    --cc=atish.patra@wdc.com \
    --cc=corbet@lwn.net \
    --cc=damien.lemoal@wdc.com \
    --cc=graf@amazon.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=kvm-riscv@lists.infradead.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-staging@lists.linux.dev \
    --cc=palmer@dabbelt.com \
    --cc=palmerdabbelt@google.com \
    --cc=paul.walmsley@sifive.com \
    --cc=pbonzini@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).