From: Lu Baolu <baolu.lu@linux.intel.com>
To: John Garry <john.garry@huawei.com>,
joro@8bytes.org, will@kernel.org, dwmw2@infradead.org,
robin.murphy@arm.com, corbet@lwn.net
Cc: baolu.lu@linux.intel.com, linux-kernel@vger.kernel.org,
iommu@lists.linux-foundation.org, linuxarm@huawei.com,
thunder.leizhen@huawei.com, chenxiang66@hisilicon.com,
linux-doc@vger.kernel.org
Subject: Re: [PATCH v13 6/6] iommu: Remove mode argument from iommu_set_dma_strict()
Date: Thu, 17 Jun 2021 15:36:52 +0800 [thread overview]
Message-ID: <de6a2874-3d6d-ed2a-78f5-fb1fb0195228@linux.intel.com> (raw)
In-Reply-To: <1623841437-211832-7-git-send-email-john.garry@huawei.com>
On 6/16/21 7:03 PM, John Garry wrote:
> We only ever now set strict mode enabled in iommu_set_dma_strict(), so
> just remove the argument.
>
> Signed-off-by: John Garry <john.garry@huawei.com>
> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
> ---
> drivers/iommu/amd/init.c | 2 +-
> drivers/iommu/intel/iommu.c | 6 +++---
> drivers/iommu/iommu.c | 5 ++---
> include/linux/iommu.h | 2 +-
> 4 files changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
> index fb3618af643b..7bc460052678 100644
> --- a/drivers/iommu/amd/init.c
> +++ b/drivers/iommu/amd/init.c
> @@ -3099,7 +3099,7 @@ static int __init parse_amd_iommu_options(char *str)
> for (; *str; ++str) {
> if (strncmp(str, "fullflush", 9) == 0) {
> pr_warn("amd_iommu=fullflush deprecated; use iommu.strict instead\n");
> - iommu_set_dma_strict(true);
> + iommu_set_dma_strict();
> }
> if (strncmp(str, "force_enable", 12) == 0)
> amd_iommu_force_enable = true;
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index d586990fa751..0618c35cfb51 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -454,7 +454,7 @@ static int __init intel_iommu_setup(char *str)
> iommu_dma_forcedac = true;
> } else if (!strncmp(str, "strict", 6)) {
> pr_warn("intel_iommu=strict deprecated; use iommu.strict instead\n");
> - iommu_set_dma_strict(true);
> + iommu_set_dma_strict();
> } else if (!strncmp(str, "sp_off", 6)) {
> pr_info("Disable supported super page\n");
> intel_iommu_superpage = 0;
> @@ -4382,7 +4382,7 @@ int __init intel_iommu_init(void)
> */
> if (cap_caching_mode(iommu->cap)) {
> pr_warn("IOMMU batching disallowed due to virtualization\n");
> - iommu_set_dma_strict(true);
> + iommu_set_dma_strict();
> }
> iommu_device_sysfs_add(&iommu->iommu, NULL,
> intel_iommu_groups,
> @@ -5699,7 +5699,7 @@ static void quirk_calpella_no_shadow_gtt(struct pci_dev *dev)
> } else if (dmar_map_gfx) {
> /* we have to ensure the gfx device is idle before we flush */
> pci_info(dev, "Disabling batched IOTLB flush on Ironlake\n");
> - iommu_set_dma_strict(true);
> + iommu_set_dma_strict();
> }
> }
> DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0040, quirk_calpella_no_shadow_gtt);
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 60b1ec42e73b..ff221d3ddcbc 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -349,10 +349,9 @@ static int __init iommu_dma_setup(char *str)
> }
> early_param("iommu.strict", iommu_dma_setup);
>
> -void iommu_set_dma_strict(bool strict)
> +void iommu_set_dma_strict(void)
> {
> - if (strict || !(iommu_cmd_line & IOMMU_CMD_LINE_STRICT))
> - iommu_dma_strict = strict;
> + iommu_dma_strict = true;
Sorry, I still can't get how iommu.strict kernel option works.
static int __init iommu_dma_setup(char *str)
{
int ret = kstrtobool(str, &iommu_dma_strict);
if (!ret)
iommu_cmd_line |= IOMMU_CMD_LINE_STRICT;
return ret;
}
early_param("iommu.strict", iommu_dma_setup);
The bit IOMMU_CMD_LINE_STRICT is only set, but not used anywhere. Hence,
I am wondering how could it work? A bug or I missed anything?
Best regards,
baolu
> }
>
> bool iommu_get_dma_strict(struct iommu_domain *domain)
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 32d448050bf7..754f67d6dd90 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -476,7 +476,7 @@ int iommu_enable_nesting(struct iommu_domain *domain);
> int iommu_set_pgtable_quirks(struct iommu_domain *domain,
> unsigned long quirks);
>
> -void iommu_set_dma_strict(bool val);
> +void iommu_set_dma_strict(void);
> bool iommu_get_dma_strict(struct iommu_domain *domain);
>
> extern int report_iommu_fault(struct iommu_domain *domain, struct device *dev,
>
next prev parent reply other threads:[~2021-06-17 7:38 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-16 11:03 [PATCH v13 0/6] iommu: Enhance IOMMU default DMA mode build options John Garry
2021-06-16 11:03 ` [PATCH v13 1/6] iommu: Deprecate Intel and AMD cmdline methods to enable strict mode John Garry
2021-06-17 19:01 ` Robin Murphy
2021-06-18 7:43 ` John Garry
2021-06-16 11:03 ` [PATCH v13 2/6] iommu: Print strict or lazy mode at init time John Garry
2021-06-16 11:03 ` [PATCH v13 3/6] iommu: Enhance IOMMU default DMA mode build options John Garry
2021-06-16 11:03 ` [PATCH v13 4/6] iommu/vt-d: Add support for " John Garry
2021-06-17 7:32 ` Lu Baolu
2021-06-17 8:00 ` John Garry
2021-06-17 19:03 ` Robin Murphy
2021-06-18 1:46 ` Lu Baolu
2021-06-18 7:31 ` John Garry
2021-06-16 11:03 ` [PATCH v13 5/6] iommu/amd: " John Garry
2021-06-16 11:03 ` [PATCH v13 6/6] iommu: Remove mode argument from iommu_set_dma_strict() John Garry
2021-06-17 7:36 ` Lu Baolu [this message]
2021-06-17 7:41 ` John Garry
2021-06-18 1:52 ` Lu Baolu
2021-06-17 18:56 ` Robin Murphy
2021-06-18 1:51 ` Lu Baolu
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=de6a2874-3d6d-ed2a-78f5-fb1fb0195228@linux.intel.com \
--to=baolu.lu@linux.intel.com \
--cc=chenxiang66@hisilicon.com \
--cc=corbet@lwn.net \
--cc=dwmw2@infradead.org \
--cc=iommu@lists.linux-foundation.org \
--cc=john.garry@huawei.com \
--cc=joro@8bytes.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxarm@huawei.com \
--cc=robin.murphy@arm.com \
--cc=thunder.leizhen@huawei.com \
--cc=will@kernel.org \
/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).