From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [Part2 PATCH v5.1 12.4/31] crypto: ccp: Implement SEV_PLATFORM_STATUS ioctl command Date: Wed, 11 Oct 2017 19:02:05 +0200 Message-ID: <20171011170205.qpu677qiqe4ludwm@pd.tnic> References: <20171004131412.13038-13-brijesh.singh@amd.com> <20171007010607.78088-1-brijesh.singh@amd.com> <20171007010607.78088-4-brijesh.singh@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Herbert Xu , Gary Hook , Tom Lendacky , linux-crypto@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: Brijesh Singh Return-path: Content-Disposition: inline In-Reply-To: <20171007010607.78088-4-brijesh.singh@amd.com> Sender: kvm-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org On Fri, Oct 06, 2017 at 08:06:02PM -0500, Brijesh Singh wrote: > The SEV_PLATFORM_STATUS command can be used by the platform owner to > get the current status of the platform. The command is defined in > SEV spec section 5.5. > > Cc: Paolo Bonzini > Cc: "Radim Krčmář" > Cc: Borislav Petkov > Cc: Herbert Xu > Cc: Gary Hook > Cc: Tom Lendacky > Cc: linux-crypto@vger.kernel.org > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Brijesh Singh > --- > drivers/crypto/ccp/psp-dev.c | 34 ++++++++++++++++++++++++++++++++++ > 1 file changed, 34 insertions(+) ... > @@ -198,6 +228,10 @@ static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) > ret = sev_handle_cmd(SEV_CMD_FACTORY_RESET, 0, &input.error); > break; > } > + case SEV_PLATFORM_STATUS: { > + ret = sev_ioctl_platform_status(&input); > + break; > + } What's with the curly brackets around the case: statements? Anyway, here are some more improvements: * you can get rid of the struct copying into out and the bitfields by doing something like this: ret = sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, &argp->error); if (ret) goto e_free; /* Clear out reserved fields: */ data->owner &= BIT(0); data->config &= BIT(0); I'm not sure those are the ones you need to clear but you get the idea - you simply poke holes in the reserved fields before copying to userspace. If you need a more sophisticated mask, use GENMASK/GENMASK_ULL. And then you don't need struct sev_user_data_status and simply remove the bitfields too. * Also, a function should have a verb in the name, thus sev_ioctl_do_platform_status(). --- diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index d668045956cb..1479db533da0 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -176,9 +176,8 @@ static int sev_do_cmd(int cmd, void *data, int *psp_ret) return ret; } -static int sev_ioctl_platform_status(struct sev_issue_cmd *argp) +static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) { - struct sev_user_data_status out; struct sev_data_status *data; int ret; @@ -186,19 +185,15 @@ static int sev_ioctl_platform_status(struct sev_issue_cmd *argp) if (!data) return -ENOMEM; - ret = sev_handle_cmd(SEV_CMD_PLATFORM_STATUS, data, &argp->error); + ret = sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, &argp->error); if (ret) goto e_free; - out.api_major = data->api_major; - out.api_minor = data->api_minor; - out.state = data->state; - out.owner = data->owner; - out.config = data->config; - out.build = data->build; - out.guest_count = data->guest_count; - if (copy_to_user((void __user *)(uintptr_t) argp->data, - &out, sizeof(struct sev_user_data_status))) + /* Clear out reserved fields: */ + data->owner &= BIT(0); + data->config &= BIT(0); + + if (copy_to_user((void __user *)argp->data, data, sizeof(*data))) ret = -EFAULT; e_free: @@ -226,10 +221,10 @@ static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) ret = sev_do_cmd(SEV_CMD_FACTORY_RESET, 0, &input.error); break; - case SEV_PLATFORM_STATUS: { - ret = sev_ioctl_platform_status(&input); + case SEV_PLATFORM_STATUS: + ret = sev_ioctl_do_platform_status(&input); break; - } + default: ret = -EINVAL; goto out; diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h index 10b843cce75f..223942ba3e7e 100644 --- a/include/linux/psp-sev.h +++ b/include/linux/psp-sev.h @@ -144,11 +144,9 @@ struct sev_data_status { u8 api_major; /* Out */ u8 api_minor; /* Out */ u8 state; /* Out */ - u8 owner : 1; /* Out */ - u8 reserved1 : 7; - u32 config : 1; /* Out */ - u32 reserved2 : 23; - u32 build : 8; /* Out */ + u8 owner; /* Out */ + u32 config; /* Out */ + u32 build; /* Out */ u32 guest_count; /* Out */ } __packed; -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --