linux-kernel - [tip: x86/mm] x86/mm: Change cpa_flush() to call flush_kernel

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Message-ID: <175588460052.1420.3714146338769865045.tip-bot2@tip-bot2>
Date: Fri, 22 Aug 2025 17:43:20 -0000
From: "tip-bot2 for Yu-cheng Yu" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: "Yu-cheng Yu" <yu-cheng.yu@...el.com>, Rik van Riel <riel@...riel.com>,
 Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: x86/mm] x86/mm: Change cpa_flush() to call flush_kernel_range()
 directly

The following commit has been merged into the x86/mm branch of tip:

Commit-ID:     86e6815b316ec0ea8c4bb3c16a033219a52b6060
Gitweb:        https://git.kernel.org/tip/86e6815b316ec0ea8c4bb3c16a033219a52b6060
Author:        Yu-cheng Yu <yu-cheng.yu@...el.com>
AuthorDate:    Fri, 06 Jun 2025 13:10:35 -04:00
Committer:     Dave Hansen <dave.hansen@...ux.intel.com>
CommitterDate: Fri, 22 Aug 2025 07:55:21 -07:00

x86/mm: Change cpa_flush() to call flush_kernel_range() directly

The function cpa_flush() calls __flush_tlb_one_kernel() and
flush_tlb_all().

Replacing that with a call to flush_tlb_kernel_range() allows
cpa_flush() to make use of INVLPGB or RAR without any additional
changes.

Initialize invlpgb_count_max to 1, since flush_tlb_kernel_range()
can now be called before invlpgb_count_max has been initialized
to the value read from CPUID.

[riel: remove now unused __cpa_flush_tlb]

Signed-off-by: Yu-cheng Yu <yu-cheng.yu@...el.com>
Signed-off-by: Rik van Riel <riel@...riel.com>
Signed-off-by: Dave Hansen <dave.hansen@...ux.intel.com>
Acked-by: Dave Hansen <dave.hansen@...ux.intel.com>
Link: https://lore.kernel.org/all/20250606171112.4013261-4-riel%40surriel.com
---
 arch/x86/mm/pat/set_memory.c | 20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 8834c76..d2d54b8 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -399,15 +399,6 @@ static void cpa_flush_all(unsigned long cache)
 	on_each_cpu(__cpa_flush_all, (void *) cache, 1);
 }
 
-static void __cpa_flush_tlb(void *data)
-{
-	struct cpa_data *cpa = data;
-	unsigned int i;
-
-	for (i = 0; i < cpa->numpages; i++)
-		flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
-}
-
 static int collapse_large_pages(unsigned long addr, struct list_head *pgtables);
 
 static void cpa_collapse_large_pages(struct cpa_data *cpa)
@@ -444,6 +435,7 @@ static void cpa_collapse_large_pages(struct cpa_data *cpa)
 
 static void cpa_flush(struct cpa_data *cpa, int cache)
 {
+	unsigned long start, end;
 	unsigned int i;
 
 	BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
@@ -453,10 +445,12 @@ static void cpa_flush(struct cpa_data *cpa, int cache)
 		goto collapse_large_pages;
 	}
 
-	if (cpa->force_flush_all || cpa->numpages > tlb_single_page_flush_ceiling)
-		flush_tlb_all();
-	else
-		on_each_cpu(__cpa_flush_tlb, cpa, 1);
+	start = fix_addr(__cpa_addr(cpa, 0));
+	end =   fix_addr(__cpa_addr(cpa, cpa->numpages));
+	if (cpa->force_flush_all)
+		end = TLB_FLUSH_ALL;
+
+	flush_tlb_kernel_range(start, end);
 
 	if (!cache)
 		goto collapse_large_pages;