diff options
| author | Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> | 2020-11-05 14:58:32 +0000 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2020-11-23 12:52:04 +0000 |
| commit | 6d39bdee238f9799718653a9d4d61ebf2922e23d (patch) | |
| tree | b0e3ab5e5730bbde6358dc42f37f418cfeb8de5e /drivers/iommu | |
| parent | 91c2c28d8de34815ea9bb4d16e9db7308ad33d3e (diff) | |
iommu/amd: Enforce 4k mapping for certain IOMMU data structures
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: c69d89aff393 ("iommu/amd: Use 4K page for completion wait write-back semaphore")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Link: https://lore.kernel.org/r/20201105145832.3065-1-suravee.suthikulpanit@amd.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/amd/init.c | 27 |
1 files 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; } |