From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> To: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: joro@8bytes.org, Jon.Grimm@amd.com, brijesh.singh@amd.com, Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Subject: [PATCH v2] iommu/amd: Enforce 4k mapping for certain IOMMU data structures Date: Thu, 5 Nov 2020 14:58:32 +0000 [thread overview] Message-ID: <20201105145832.3065-1-suravee.suthikulpanit@amd.com> (raw) AMD IOMMU requires 4k-aligned pages for the event log, the PPR log, and the completion wait write-back regions. However, when allocating the pages, they could be part of large mapping (e.g. 2M) page. This causes #PF due to the SNP RMP hardware enforces the check based on the page level for these data structures. So, fix by calling set_memory_4k() on the allocated pages. Fixes: commit c69d89aff393 ("iommu/amd: Use 4K page for completion wait write-back semaphore") Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> --- drivers/iommu/amd/init.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 82e4af8f09bb..23a790f8f550 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -29,6 +29,7 @@ #include <asm/iommu_table.h> #include <asm/io_apic.h> #include <asm/irq_remapping.h> +#include <asm/set_memory.h> #include <linux/crash_dump.h> @@ -672,11 +673,27 @@ static void __init free_command_buffer(struct amd_iommu *iommu) free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE)); } +static void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu, + gfp_t gfp, size_t size) +{ + int order = get_order(size); + void *buf = (void *)__get_free_pages(gfp, order); + + if (buf && + iommu_feature(iommu, FEATURE_SNP) && + set_memory_4k((unsigned long)buf, (1 << order))) { + free_pages((unsigned long)buf, order); + buf = NULL; + } + + return buf; +} + /* allocates the memory where the IOMMU will log its events to */ static int __init alloc_event_buffer(struct amd_iommu *iommu) { - iommu->evt_buf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - get_order(EVT_BUFFER_SIZE)); + iommu->evt_buf = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, + EVT_BUFFER_SIZE); return iommu->evt_buf ? 0 : -ENOMEM; } @@ -715,8 +732,8 @@ static void __init free_event_buffer(struct amd_iommu *iommu) /* allocates the memory where the IOMMU will log its events to */ static int __init alloc_ppr_log(struct amd_iommu *iommu) { - iommu->ppr_log = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - get_order(PPR_LOG_SIZE)); + iommu->ppr_log = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, + PPR_LOG_SIZE); return iommu->ppr_log ? 0 : -ENOMEM; } @@ -838,7 +855,7 @@ static int iommu_init_ga(struct amd_iommu *iommu) static int __init alloc_cwwb_sem(struct amd_iommu *iommu) { - iommu->cmd_sem = (void *)get_zeroed_page(GFP_KERNEL); + iommu->cmd_sem = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, 1); return iommu->cmd_sem ? 0 : -ENOMEM; } -- 2.17.1
WARNING: multiple messages have this Message-ID (diff)
From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> To: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: Jon.Grimm@amd.com, brijesh.singh@amd.com Subject: [PATCH v2] iommu/amd: Enforce 4k mapping for certain IOMMU data structures Date: Thu, 5 Nov 2020 14:58:32 +0000 [thread overview] Message-ID: <20201105145832.3065-1-suravee.suthikulpanit@amd.com> (raw) AMD IOMMU requires 4k-aligned pages for the event log, the PPR log, and the completion wait write-back regions. However, when allocating the pages, they could be part of large mapping (e.g. 2M) page. This causes #PF due to the SNP RMP hardware enforces the check based on the page level for these data structures. So, fix by calling set_memory_4k() on the allocated pages. Fixes: commit c69d89aff393 ("iommu/amd: Use 4K page for completion wait write-back semaphore") Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> --- drivers/iommu/amd/init.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 82e4af8f09bb..23a790f8f550 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -29,6 +29,7 @@ #include <asm/iommu_table.h> #include <asm/io_apic.h> #include <asm/irq_remapping.h> +#include <asm/set_memory.h> #include <linux/crash_dump.h> @@ -672,11 +673,27 @@ static void __init free_command_buffer(struct amd_iommu *iommu) free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE)); } +static void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu, + gfp_t gfp, size_t size) +{ + int order = get_order(size); + void *buf = (void *)__get_free_pages(gfp, order); + + if (buf && + iommu_feature(iommu, FEATURE_SNP) && + set_memory_4k((unsigned long)buf, (1 << order))) { + free_pages((unsigned long)buf, order); + buf = NULL; + } + + return buf; +} + /* allocates the memory where the IOMMU will log its events to */ static int __init alloc_event_buffer(struct amd_iommu *iommu) { - iommu->evt_buf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - get_order(EVT_BUFFER_SIZE)); + iommu->evt_buf = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, + EVT_BUFFER_SIZE); return iommu->evt_buf ? 0 : -ENOMEM; } @@ -715,8 +732,8 @@ static void __init free_event_buffer(struct amd_iommu *iommu) /* allocates the memory where the IOMMU will log its events to */ static int __init alloc_ppr_log(struct amd_iommu *iommu) { - iommu->ppr_log = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - get_order(PPR_LOG_SIZE)); + iommu->ppr_log = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, + PPR_LOG_SIZE); return iommu->ppr_log ? 0 : -ENOMEM; } @@ -838,7 +855,7 @@ static int iommu_init_ga(struct amd_iommu *iommu) static int __init alloc_cwwb_sem(struct amd_iommu *iommu) { - iommu->cmd_sem = (void *)get_zeroed_page(GFP_KERNEL); + iommu->cmd_sem = iommu_alloc_4k_pages(iommu, GFP_KERNEL | __GFP_ZERO, 1); return iommu->cmd_sem ? 0 : -ENOMEM; } -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
next reply other threads:[~2020-11-05 14:59 UTC|newest] Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-11-05 14:58 Suravee Suthikulpanit [this message] 2020-11-05 14:58 ` [PATCH v2] iommu/amd: Enforce 4k mapping for certain IOMMU data structures Suravee Suthikulpanit 2020-11-20 2:30 ` Suravee Suthikulpanit 2020-11-20 2:30 ` Suravee Suthikulpanit 2020-11-20 4:19 ` Brijesh Singh 2020-11-20 4:19 ` Brijesh Singh 2020-11-23 14:56 ` Will Deacon 2020-11-23 14:56 ` Will Deacon
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=20201105145832.3065-1-suravee.suthikulpanit@amd.com \ --to=suravee.suthikulpanit@amd.com \ --cc=Jon.Grimm@amd.com \ --cc=brijesh.singh@amd.com \ --cc=iommu@lists.linux-foundation.org \ --cc=joro@8bytes.org \ --cc=linux-kernel@vger.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: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.