Message-ID: <eb073b008b547cf87722390cc94fe6e9d21c514e.1756151769.git.maciej.wieczor-retman@intel.com>
Date: Mon, 25 Aug 2025 22:24:39 +0200
From: Maciej Wieczor-Retman <maciej.wieczor-retman@...el.com>
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Subject: [PATCH v5 14/19] arm64: Unify software tag-based KASAN inline recovery path

To avoid having a copy of a long comment explaining the intricacies of
the inline KASAN recovery system and issues for every architecture that
uses the software tag-based mode, a unified kasan_inline_recover()
function was added.

Use kasan_inline_recover() in the kasan brk handler to cleanup the long
comment, that's kept in the non-arch KASAN code.

Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@...el.com>
---
Changelog v5:
- Split arm64 portion of patch 13/18 into this one. (Peter Zijlstra)

 arch/arm64/kernel/traps.c | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index f528b6041f6a..fe3c0104fe31 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -1068,22 +1068,7 @@ int kasan_brk_handler(struct pt_regs *regs, unsigned long esr)
 
 	kasan_report(addr, size, write, pc);
 
-	/*
-	 * The instrumentation allows to control whether we can proceed after
-	 * a crash was detected. This is done by passing the -recover flag to
-	 * the compiler. Disabling recovery allows to generate more compact
-	 * code.
-	 *
-	 * Unfortunately disabling recovery doesn't work for the kernel right
-	 * now. KASAN reporting is disabled in some contexts (for example when
-	 * the allocator accesses slab object metadata; this is controlled by
-	 * current->kasan_depth). All these accesses are detected by the tool,
-	 * even though the reports for them are not printed.
-	 *
-	 * This is something that might be fixed at some point in the future.
-	 */
-	if (!recover)
-		die("Oops - KASAN", regs, esr);
+	kasan_inline_recover(recover, "Oops - KASAN", regs, esr, die);
 
 	/* If thread survives, skip over the brk instruction and continue: */
 	arm64_skip_faulting_instruction(regs, AARCH64_INSN_SIZE);
-- 
2.50.1

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