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From: Christophe Leroy <christophe.leroy@csgroup.eu>
To: Benjamin Gray <bgray@linux.ibm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: [PATCH v1 2/6] powerpc/code-patching: Remove #ifdef CONFIG_STRICT_KERNEL_RWX
Date: Tue, 27 Sep 2022 16:33:04 +0200	[thread overview]
Message-ID: <6afd19a3f6499dca52f1eb89940e7dcb3660b66c.1664289176.git.christophe.leroy@csgroup.eu> (raw)
In-Reply-To: <b0aac2127d30c32e5742e978045c5793667bb7ce.1664289176.git.christophe.leroy@csgroup.eu>

No need to have one implementation of patch_instruction() for
CONFIG_STRICT_KERNEL_RWX and one for !CONFIG_STRICT_KERNEL_RWX.

In patch_instruction(), call raw_patch_instruction() when
!CONFIG_STRICT_KERNEL_RWX.

In poking_init(), bail out immediately, it will be equivalent
to the weak default implementation.

Everything else is declared static and will be discarded by
GCC when !CONFIG_STRICT_KERNEL_RWX.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/lib/code-patching.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 0f3acb0534b6..647a0bb35848 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -41,7 +41,6 @@ int raw_patch_instruction(u32 *addr, ppc_inst_t instr)
 	return __patch_instruction(addr, instr, addr);
 }
 
-#ifdef CONFIG_STRICT_KERNEL_RWX
 static DEFINE_PER_CPU(struct vm_struct *, text_poke_area);
 
 static int map_patch_area(void *addr, unsigned long text_poke_addr);
@@ -88,6 +87,9 @@ static __ro_after_init DEFINE_STATIC_KEY_FALSE(poking_init_done);
  */
 void __init poking_init(void)
 {
+	if (!IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
+		return;
+
 	BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
 		"powerpc/text_poke:online", text_area_cpu_up,
 		text_area_cpu_down));
@@ -182,7 +184,8 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
 	 * when text_poke_area is not ready, but we still need
 	 * to allow patching. We just do the plain old patching
 	 */
-	if (!static_branch_likely(&poking_init_done))
+	if (!IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) ||
+	    !static_branch_likely(&poking_init_done))
 		return raw_patch_instruction(addr, instr);
 
 	local_irq_save(flags);
@@ -191,14 +194,6 @@ static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
 
 	return err;
 }
-#else /* !CONFIG_STRICT_KERNEL_RWX */
-
-static int do_patch_instruction(u32 *addr, ppc_inst_t instr)
-{
-	return raw_patch_instruction(addr, instr);
-}
-
-#endif /* CONFIG_STRICT_KERNEL_RWX */
 
 __ro_after_init DEFINE_STATIC_KEY_FALSE(init_mem_is_free);
 
-- 
2.37.1


  reply	other threads:[~2022-09-27 14:35 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-03-22 15:40 [PATCH v1 0/4] Kill the time spent in patch_instruction() Christophe Leroy
2022-03-22 15:40 ` [PATCH v1 1/4] powerpc/code-patching: Don't call is_vmalloc_or_module_addr() without CONFIG_MODULES Christophe Leroy
2022-09-27 14:33   ` Christophe Leroy
2022-03-22 15:40 ` [PATCH v1 2/4] powerpc/code-patching: Speed up page mapping/unmapping Christophe Leroy
2022-09-27 14:33   ` Christophe Leroy
2022-03-22 15:40 ` [PATCH v1 3/4] powerpc/code-patching: Use jump_label for testing freed initmem Christophe Leroy
2022-05-19  2:17   ` Guenter Roeck
2022-05-19  6:27     ` Christophe Leroy
2022-05-19  6:53       ` Christophe Leroy
2022-05-19 17:27         ` Christophe Leroy
2022-09-27 14:33   ` Christophe Leroy
2022-03-22 15:40 ` [PATCH v1 4/4] powerpc/code-patching: Use jump_label to check if poking_init() is done Christophe Leroy
2022-09-27 14:33   ` Christophe Leroy
2022-05-15 10:28 ` [PATCH v1 0/4] Kill the time spent in patch_instruction() Michael Ellerman
2022-05-17  6:44   ` Christophe Leroy
2022-05-17 12:37     ` Michael Ellerman
2022-05-31  6:24       ` Christophe Leroy
2022-06-24  7:06         ` Christophe Leroy
2022-09-27 14:33 ` Christophe Leroy
2022-09-27 14:33 ` [PATCH v1 1/6] powerpc/code-patching: Use pte_offset_kernel() instead of virt_to_kpte() Christophe Leroy
2022-09-27 14:33   ` Christophe Leroy [this message]
2022-09-27 14:33   ` [PATCH v1 3/6] powerpc/feature-fixups: Refactor entry fixups patching Christophe Leroy
2022-09-27 14:33   ` [PATCH v1 4/6] powerpc/feature-fixups: Refactor other " Christophe Leroy
2022-09-27 14:33   ` [PATCH v1 5/6] powerpc/feature-fixups: Do not patch init section after init Christophe Leroy
2022-09-27 14:33   ` [PATCH v1 6/6] powerpc/code-patching: Remove protection against patching init addresses " Christophe Leroy
2022-09-27 14:38 ` [PATCH v1 0/4] Kill the time spent in patch_instruction() Christophe Leroy

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