From 8ea815399c3fcce1889bd951fec25b5b9a3979c1 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 14 Apr 2025 16:41:07 +0200 Subject: [PATCH 1/2] compiler: remove __ADDRESSABLE_ASM{_STR,}() again __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 Acked-by: Josh Poimboeuf Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross Message-ID: <609d2c74-de13-4fae-ab1a-1ec44afb948d@suse.com> --- arch/x86/include/asm/xen/hypercall.h | 5 +++-- include/linux/compiler.h | 8 -------- 2 files changed, 3 insertions(+), 10 deletions(-) diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h index 59a62c3780a2..a16d4631547c 100644 --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -94,12 +94,13 @@ 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) diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 6f04a1d8c720..64ff73c533e5 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -288,14 +288,6 @@ static inline void *offset_to_ptr(const int *off) #define __ADDRESSABLE(sym) \ ___ADDRESSABLE(sym, __section(".discard.addressable")) -#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)) - /* * This returns a constant expression while determining if an argument is * a constant expression, most importantly without evaluating the argument. From efdaa61d73a1deb066ccc3b4d56257cc63ab5be9 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 15 Aug 2025 09:40:52 +0200 Subject: [PATCH 2/2] drivers/xen/xenbus: remove quirk for Xen 3.x The kernel is not supported to run as a Xen guest on Xen versions older than 4.0. Remove xen_strict_xenbus_quirk() which is testing the Xen version to be at least 4.0. Acked-by: Stefano Stabellini Reviewed-by: Jason Andryuk Signed-off-by: Juergen Gross Message-ID: <20250815074052.13792-1-jgross@suse.com> --- drivers/xen/xenbus/xenbus_xs.c | 23 ----------------------- 1 file changed, 23 deletions(-) diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index 3c9da446b85d..528682bf0c7f 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -718,26 +718,6 @@ int xs_watch_msg(struct xs_watch_event *event) return 0; } -/* - * Certain older XenBus toolstack cannot handle reading values that are - * not populated. Some Xen 3.4 installation are incapable of doing this - * so if we are running on anything older than 4 do not attempt to read - * control/platform-feature-xs_reset_watches. - */ -static bool xen_strict_xenbus_quirk(void) -{ -#ifdef CONFIG_X86 - uint32_t eax, ebx, ecx, edx, base; - - base = xen_cpuid_base(); - cpuid(base + 1, &eax, &ebx, &ecx, &edx); - - if ((eax >> 16) < 4) - return true; -#endif - return false; - -} static void xs_reset_watches(void) { int err; @@ -745,9 +725,6 @@ static void xs_reset_watches(void) if (!xen_hvm_domain() || xen_initial_domain()) return; - if (xen_strict_xenbus_quirk()) - return; - if (!xenbus_read_unsigned("control", "platform-feature-xs_reset_watches", 0)) return;