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-rw-r--r--system/xen/xsa/xsa373-4.15-3.patch163
1 files changed, 0 insertions, 163 deletions
diff --git a/system/xen/xsa/xsa373-4.15-3.patch b/system/xen/xsa/xsa373-4.15-3.patch
deleted file mode 100644
index c7ddf5d6441ce..0000000000000
--- a/system/xen/xsa/xsa373-4.15-3.patch
+++ /dev/null
@@ -1,163 +0,0 @@
-From: Jan Beulich <jbeulich@suse.com>
-Subject: VT-d: eliminate flush related timeouts
-
-Leaving an in-progress operation pending when it appears to take too
-long is problematic: If e.g. a QI command completed later, the write to
-the "poll slot" may instead be understood to signal a subsequently
-started command's completion. Also our accounting of the timeout period
-was actually wrong: We included the time it took for the command to
-actually make it to the front of the queue, which could be heavily
-affected by guests other than the one for which the flush is being
-performed.
-
-Do away with all timeout detection on all flush related code paths.
-Log excessively long processing times (with a progressive threshold) to
-have some indication of problems in this area.
-
-Additionally log (once) if qinval_next_index() didn't immediately find
-an available slot. Together with the earlier change sizing the queue(s)
-dynamically, we should now have a guarantee that with our fully
-synchronous model any demand for slots can actually be satisfied.
-
-This is part of XSA-373 / CVE-2021-28692.
-
-Signed-off-by: Jan Beulich <jbeulich@suse.com>
-Reviewed-by: Paul Durrant <paul@xen.org>
-
---- a/xen/drivers/passthrough/vtd/dmar.h
-+++ b/xen/drivers/passthrough/vtd/dmar.h
-@@ -127,6 +127,34 @@ do {
- } \
- } while (0)
-
-+#define IOMMU_FLUSH_WAIT(what, iommu, offset, op, cond, sts) \
-+do { \
-+ static unsigned int __read_mostly threshold = 1; \
-+ s_time_t start = NOW(); \
-+ s_time_t timeout = start + DMAR_OPERATION_TIMEOUT * threshold; \
-+ \
-+ for ( ; ; ) \
-+ { \
-+ sts = op(iommu->reg, offset); \
-+ if ( cond ) \
-+ break; \
-+ if ( timeout && NOW() > timeout ) \
-+ { \
-+ threshold |= threshold << 1; \
-+ printk(XENLOG_WARNING VTDPREFIX \
-+ " IOMMU#%u: %s flush taking too long\n", \
-+ iommu->index, what); \
-+ timeout = 0; \
-+ } \
-+ cpu_relax(); \
-+ } \
-+ \
-+ if ( !timeout ) \
-+ printk(XENLOG_WARNING VTDPREFIX \
-+ " IOMMU#%u: %s flush took %lums\n", \
-+ iommu->index, what, (NOW() - start) / 10000000); \
-+} while ( false )
-+
- int vtd_hw_check(void);
- void disable_pmr(struct vtd_iommu *iommu);
- int is_igd_drhd(struct acpi_drhd_unit *drhd);
---- a/xen/drivers/passthrough/vtd/iommu.c
-+++ b/xen/drivers/passthrough/vtd/iommu.c
-@@ -373,8 +373,8 @@ static void iommu_flush_write_buffer(str
- dmar_writel(iommu->reg, DMAR_GCMD_REG, val | DMA_GCMD_WBF);
-
- /* Make sure hardware complete it */
-- IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, dmar_readl,
-- !(val & DMA_GSTS_WBFS), val);
-+ IOMMU_FLUSH_WAIT("write buffer", iommu, DMAR_GSTS_REG, dmar_readl,
-+ !(val & DMA_GSTS_WBFS), val);
-
- spin_unlock_irqrestore(&iommu->register_lock, flags);
- }
-@@ -423,8 +423,8 @@ int vtd_flush_context_reg(struct vtd_iom
- dmar_writeq(iommu->reg, DMAR_CCMD_REG, val);
-
- /* Make sure hardware complete it */
-- IOMMU_WAIT_OP(iommu, DMAR_CCMD_REG, dmar_readq,
-- !(val & DMA_CCMD_ICC), val);
-+ IOMMU_FLUSH_WAIT("context", iommu, DMAR_CCMD_REG, dmar_readq,
-+ !(val & DMA_CCMD_ICC), val);
-
- spin_unlock_irqrestore(&iommu->register_lock, flags);
- /* flush context entry will implicitly flush write buffer */
-@@ -501,8 +501,8 @@ int vtd_flush_iotlb_reg(struct vtd_iommu
- dmar_writeq(iommu->reg, tlb_offset + 8, val);
-
- /* Make sure hardware complete it */
-- IOMMU_WAIT_OP(iommu, (tlb_offset + 8), dmar_readq,
-- !(val & DMA_TLB_IVT), val);
-+ IOMMU_FLUSH_WAIT("iotlb", iommu, (tlb_offset + 8), dmar_readq,
-+ !(val & DMA_TLB_IVT), val);
- spin_unlock_irqrestore(&iommu->register_lock, flags);
-
- /* check IOTLB invalidation granularity */
---- a/xen/drivers/passthrough/vtd/qinval.c
-+++ b/xen/drivers/passthrough/vtd/qinval.c
-@@ -29,8 +29,6 @@
- #include "extern.h"
- #include "../ats.h"
-
--#define VTD_QI_TIMEOUT 1
--
- static unsigned int __read_mostly qi_pg_order;
- static unsigned int __read_mostly qi_entry_nr;
-
-@@ -60,7 +58,11 @@ static unsigned int qinval_next_index(st
- /* (tail+1 == head) indicates a full queue, wait for HW */
- while ( ((tail + 1) & (qi_entry_nr - 1)) ==
- ( dmar_readq(iommu->reg, DMAR_IQH_REG) >> QINVAL_INDEX_SHIFT ) )
-+ {
-+ printk_once(XENLOG_ERR VTDPREFIX " IOMMU#%u: no QI slot available\n",
-+ iommu->index);
- cpu_relax();
-+ }
-
- return tail;
- }
-@@ -180,23 +182,32 @@ static int __must_check queue_invalidate
- /* Now we don't support interrupt method */
- if ( sw )
- {
-- s_time_t timeout;
--
-- /* In case all wait descriptor writes to same addr with same data */
-- timeout = NOW() + MILLISECS(flush_dev_iotlb ?
-- iommu_dev_iotlb_timeout : VTD_QI_TIMEOUT);
-+ static unsigned int __read_mostly threshold = 1;
-+ s_time_t start = NOW();
-+ s_time_t timeout = start + (flush_dev_iotlb
-+ ? iommu_dev_iotlb_timeout
-+ : 100) * MILLISECS(threshold);
-
- while ( ACCESS_ONCE(*this_poll_slot) != QINVAL_STAT_DONE )
- {
-- if ( NOW() > timeout )
-+ if ( timeout && NOW() > timeout )
- {
-- print_qi_regs(iommu);
-+ threshold |= threshold << 1;
- printk(XENLOG_WARNING VTDPREFIX
-- " Queue invalidate wait descriptor timed out\n");
-- return -ETIMEDOUT;
-+ " IOMMU#%u: QI%s wait descriptor taking too long\n",
-+ iommu->index, flush_dev_iotlb ? " dev" : "");
-+ print_qi_regs(iommu);
-+ timeout = 0;
- }
- cpu_relax();
- }
-+
-+ if ( !timeout )
-+ printk(XENLOG_WARNING VTDPREFIX
-+ " IOMMU#%u: QI%s wait descriptor took %lums\n",
-+ iommu->index, flush_dev_iotlb ? " dev" : "",
-+ (NOW() - start) / 10000000);
-+
- return 0;
- }
-
generated by cgit v1.2.3 (git 2.26.2) at 2025-02-08 17:47:30 +0000