summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-02-17 17:34:25 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-02-22 14:47:20 +0300
commite136657a7aa393eda7f78120e7eac5762ba08ec1 (patch)
tree68aa7c742a1218842cdba50a9492498440fbf59a
parent0b21edf4cc13516716848e0a4fdf726aa2a62cd9 (diff)
downloadlinux-e136657a7aa393eda7f78120e7eac5762ba08ec1.tar.xz
Revert "x86/fpu: Use _Alignof to avoid undefined behavior in TYPE_ALIGN"
This reverts commit a00d020f18dbe0666e221d929846f1b591b27c20 which is commit 55228db2697c09abddcb9487c3d9fa5854a932cd upstream. _Alignof is not in the gcc version that the 4.19.y kernel still supports (4.6), so this change needs to be reverted as it breaks the build on those older compiler versions. Reported-by: Michael Nies <michael.nies@netclusive.com> Link: https://lore.kernel.org/r/HE1PR0902MB188277E37DED663AE440510BE1D99@HE1PR0902MB1882.eurprd09.prod.outlook.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=217013 Cc: YingChi Long <me@inclyc.cn> Cc: Borislav Petkov <bp@suse.de> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/kernel/fpu/init.c7
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index a3a570df6be1..9692ccc583bb 100644
--- a/arch/x86/kernel/fpu/init.c
+++ b/arch/x86/kernel/fpu/init.c
@@ -138,6 +138,9 @@ static void __init fpu__init_system_generic(void)
unsigned int fpu_kernel_xstate_size;
EXPORT_SYMBOL_GPL(fpu_kernel_xstate_size);
+/* Get alignment of the TYPE. */
+#define TYPE_ALIGN(TYPE) offsetof(struct { char x; TYPE test; }, test)
+
/*
* Enforce that 'MEMBER' is the last field of 'TYPE'.
*
@@ -145,8 +148,8 @@ EXPORT_SYMBOL_GPL(fpu_kernel_xstate_size);
* because that's how C aligns structs.
*/
#define CHECK_MEMBER_AT_END_OF(TYPE, MEMBER) \
- BUILD_BUG_ON(sizeof(TYPE) != \
- ALIGN(offsetofend(TYPE, MEMBER), _Alignof(TYPE)))
+ BUILD_BUG_ON(sizeof(TYPE) != ALIGN(offsetofend(TYPE, MEMBER), \
+ TYPE_ALIGN(TYPE)))
/*
* We append the 'struct fpu' to the task_struct: