From: Thorsten Blum <thorsten.blum@linux.dev>
To: Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Thorsten Blum <thorsten.blum@linux.dev>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] x86/kaslr: Remove redundant if checks from address selection
Date: Fri, 26 Jun 2026 12:14:12 +0200 [thread overview]
Message-ID: <20260626101412.2929-2-thorsten.blum@linux.dev> (raw)
The loop in slots_fetch_random() either returns the slot address or
exits with i == slot_area_index, making the if check redundant.
The if check in choose_random_location() is also unnecessary since
commit 8570978ea030 ("x86/boot/compressed/64: Don't pre-map memory in
KASLR code").
Remove both if checks.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
arch/x86/boot/compressed/kaslr.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 71265a0733f7..371a00aba170 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -544,8 +544,7 @@ static u64 slots_fetch_random(void)
return slot_areas[i].addr + ((u64)slot * CONFIG_PHYSICAL_ALIGN);
}
- if (i == slot_area_index)
- debug_putstr("slots_fetch_random() failed!?\n");
+ debug_putstr("slots_fetch_random() failed!?\n");
return 0;
}
@@ -893,14 +892,10 @@ void choose_random_location(unsigned long input,
/* Walk available memory entries to find a random address. */
random_addr = find_random_phys_addr(min_addr, output_size);
- if (!random_addr) {
+ if (!random_addr)
warn("Physical KASLR disabled: no suitable memory region!");
- } else {
- /* Update the new physical address location. */
- if (*output != random_addr)
- *output = random_addr;
- }
-
+ else
+ *output = random_addr;
/* Pick random virtual address starting from LOAD_PHYSICAL_ADDR. */
if (IS_ENABLED(CONFIG_X86_64))
reply other threads:[~2026-06-26 10:15 UTC|newest]
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