compiler: remove __ADDRESSABLE_ASM{_STR,}() again

[ Upstream commit 8ea815399c3fcce1889bd951fec25b5b9a3979c1 ]

__ADDRESSABLE_ASM_STR() is where the necessary stringification happens.
As long as "sym" doesn't contain any odd characters, no quoting is
required for its use with .quad / .long. In fact the quotation gets in
the way with gas 2.25; it's only from 2.26 onwards that quoted symbols
are half-way properly supported.

However, assembly being different from C anyway, drop
__ADDRESSABLE_ASM_STR() and its helper macro altogether. A simple
.global directive will suffice to get the symbol "declared", i.e. into
the symbol table. While there also stop open-coding STATIC_CALL_TRAMP()
and STATIC_CALL_KEY().

Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <609d2c74-de13-4fae-ab1a-1ec44afb948d@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jan Beulich
2025-08-24 14:30:52 -04:00
committed by Greg Kroah-Hartman
parent c010b7a9e1
commit 27b32b2c7b
2 changed files with 4 additions and 10 deletions

View File

@@ -37,6 +37,7 @@
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/stringify.h>
#include <linux/types.h>
#include <linux/pgtable.h>
#include <linux/instrumentation.h>
@@ -94,12 +95,13 @@ DECLARE_STATIC_CALL(xen_hypercall, xen_hypercall_func);
#ifdef MODULE
#define __ADDRESSABLE_xen_hypercall
#else
#define __ADDRESSABLE_xen_hypercall __ADDRESSABLE_ASM_STR(__SCK__xen_hypercall)
#define __ADDRESSABLE_xen_hypercall \
__stringify(.global STATIC_CALL_KEY(xen_hypercall);)
#endif
#define __HYPERCALL \
__ADDRESSABLE_xen_hypercall \
"call __SCT__xen_hypercall"
__stringify(call STATIC_CALL_TRAMP(xen_hypercall))
#define __HYPERCALL_ENTRY(x) "a" (x)

View File

@@ -242,14 +242,6 @@ static inline void *offset_to_ptr(const int *off)
static void * __section(".discard.addressable") __used \
__UNIQUE_ID(__PASTE(__addressable_,sym)) = (void *)&sym;
#define __ADDRESSABLE_ASM(sym) \
.pushsection .discard.addressable,"aw"; \
.align ARCH_SEL(8,4); \
ARCH_SEL(.quad, .long) __stringify(sym); \
.popsection;
#define __ADDRESSABLE_ASM_STR(sym) __stringify(__ADDRESSABLE_ASM(sym))
/* &a[0] degrades to a pointer: a different type from an array */
#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))