The following commit has been merged into the timers/vdso branch of tip:
Commit-ID: feffe3a9d4b0d1672db4c16457f029f1c22b35da
Gitweb: https://git.kernel.org/tip/feffe3a9d4b0d1672db4c16457f029f1c22b35da
Author: Ian Rogers <irogers@google.com>
AuthorDate: Thu, 16 Oct 2025 13:51:23 -07:00
Committer: Thomas Gleixner <tglx@kernel.org>
CommitterDate: Tue, 13 Jan 2026 14:46:00 +01:00
parisc: Inline a type punning version of get_unaligned_le32()
Reading the byte/char output_len with get_unaligned_le32() can trigger
compiler warnings due to the size read. Avoid these warnings by using
type punning. This avoids issues when switching get_unaligned_t() to
__builtin_memcpy().
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20251016205126.2882625-2-irogers@google.com
---
arch/parisc/boot/compressed/misc.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/arch/parisc/boot/compressed/misc.c b/arch/parisc/boot/compressed/misc.c
index 9c83bd0..111f267 100644
--- a/arch/parisc/boot/compressed/misc.c
+++ b/arch/parisc/boot/compressed/misc.c
@@ -278,6 +278,19 @@ static void parse_elf(void *output)
free(phdrs);
}
+/*
+ * The regular get_unaligned_le32 uses __builtin_memcpy which can trigger
+ * warnings when reading a byte/char output_len as an integer, as the size of a
+ * char is less than that of an integer. Use type punning and the packed
+ * attribute, which requires -fno-strict-aliasing, to work around the problem.
+ */
+static u32 punned_get_unaligned_le32(const void *p)
+{
+ const struct { __le32 x; } __packed * __get_pptr = p;
+
+ return le32_to_cpu(__get_pptr->x);
+}
+
asmlinkage unsigned long __visible decompress_kernel(unsigned int started_wide,
unsigned int command_line,
const unsigned int rd_start,
@@ -309,7 +322,7 @@ asmlinkage unsigned long __visible decompress_kernel(unsigned int started_wide,
* leave 2 MB for the stack.
*/
vmlinux_addr = (unsigned long) &_ebss + 2*1024*1024;
- vmlinux_len = get_unaligned_le32(&output_len);
+ vmlinux_len = punned_get_unaligned_le32(&output_len);
output = (char *) vmlinux_addr;
/*