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Subject[PATCH 01/10] x86/mm/cpa: Fix cpa_flush_array() TLB invalidation
In commit:

a7295fd53c39 ("x86/mm/cpa: Use flush_tlb_kernel_range()")

I misread the cpa array code and incorrectly used
tlb_flush_kernel_range(), resulting in missing TLB flushes and
consequent failures.

Instead do a full invalidate in this case -- for now.

Fixes: a7295fd53c39 ("x86/mm/cpa: Use flush_tlb_kernel_range()")
Reported-by: "StDenis, Tom" <Tom.StDenis@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/mm/pageattr.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index bac35001d896..61bc7d1800d7 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -285,20 +285,16 @@ static void cpa_flush_all(unsigned long cache)
on_each_cpu(__cpa_flush_all, (void *) cache, 1);
}

-static bool __cpa_flush_range(unsigned long start, int numpages, int cache)
+static bool __inv_flush_all(int cache)
{
BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);

- WARN_ON(PAGE_ALIGN(start) != start);
-
if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
cpa_flush_all(cache);
return true;
}

- flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages);
-
- return !cache;
+ return false;
}

static void cpa_flush_range(unsigned long start, int numpages, int cache)
@@ -306,7 +302,14 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache)
unsigned int i, level;
unsigned long addr;

- if (__cpa_flush_range(start, numpages, cache))
+ WARN_ON(PAGE_ALIGN(start) != start);
+
+ if (__inv_flush_all(cache))
+ return;
+
+ flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages);
+
+ if (!cache)
return;

/*
@@ -332,7 +335,12 @@ static void cpa_flush_array(unsigned long baddr, unsigned long *start,
{
unsigned int i, level;

- if (__cpa_flush_range(baddr, numpages, cache))
+ if (__inv_flush_all(cache))
+ return;
+
+ flush_tlb_all();
+
+ if (!cache)
return;

/*

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