[PATCH AUTOSEL 6.5 40/52] LoongArch: Use SYM_CODE_* to annotate exception handlers

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* [PATCH AUTOSEL 6.5 40/52] LoongArch: Use SYM_CODE_* to annotate exception handlers
       [not found] <20231029225441.789781-1-sashal@kernel.org>
@ 2023-10-29 22:53 ` Sasha Levin
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 41/52] LoongArch: Export symbol invalid_pud_table for modules building Sasha Levin
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2023-10-29 22:53 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Tiezhu Yang, Huacai Chen, Sasha Levin, chenhuacai, zhoubinbin,
	xry111, lihui, zhangqing, hejinyang, tangyouling, git, yijun,
	masahiroy, loongarch

From: Tiezhu Yang <yangtiezhu@loongson.cn>

[ Upstream commit 00c2ca84c680f64b79b5e10a482ca435fd7d98ce ]

As described in include/linux/linkage.h,

  FUNC -- C-like functions (proper stack frame etc.)
  CODE -- non-C code (e.g. irq handlers with different, special stack etc.)

  SYM_FUNC_{START, END} -- use for global functions
  SYM_CODE_{START, END} -- use for non-C (special) functions

So use SYM_CODE_* to annotate exception handlers.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/loongarch/include/asm/linkage.h |  8 +++++++
 arch/loongarch/kernel/entry.S        |  4 ++--
 arch/loongarch/kernel/genex.S        | 16 ++++++-------
 arch/loongarch/mm/tlbex.S            | 36 ++++++++++++++--------------
 4 files changed, 36 insertions(+), 28 deletions(-)

diff --git a/arch/loongarch/include/asm/linkage.h b/arch/loongarch/include/asm/linkage.h
index 81b0c4cfbf4f2..e2eca1a25b4ef 100644
--- a/arch/loongarch/include/asm/linkage.h
+++ b/arch/loongarch/include/asm/linkage.h
@@ -33,4 +33,12 @@
 	.cfi_endproc;					\
 	SYM_END(name, SYM_T_FUNC)
 
+#define SYM_CODE_START(name)				\
+	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
+	.cfi_startproc;
+
+#define SYM_CODE_END(name)				\
+	.cfi_endproc;					\
+	SYM_END(name, SYM_T_NONE)
+
 #endif
diff --git a/arch/loongarch/kernel/entry.S b/arch/loongarch/kernel/entry.S
index d737e3cf42d3f..1781c6a5befa2 100644
--- a/arch/loongarch/kernel/entry.S
+++ b/arch/loongarch/kernel/entry.S
@@ -18,7 +18,7 @@
 	.text
 	.cfi_sections	.debug_frame
 	.align	5
-SYM_FUNC_START(handle_syscall)
+SYM_CODE_START(handle_syscall)
 	csrrd		t0, PERCPU_BASE_KS
 	la.pcrel	t1, kernelsp
 	add.d		t1, t1, t0
@@ -66,7 +66,7 @@ SYM_FUNC_START(handle_syscall)
 	bl		do_syscall
 
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_syscall)
+SYM_CODE_END(handle_syscall)
 _ASM_NOKPROBE(handle_syscall)
 
 SYM_CODE_START(ret_from_fork)
diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S
index 78f0663846575..2bb3aa2dcfcb2 100644
--- a/arch/loongarch/kernel/genex.S
+++ b/arch/loongarch/kernel/genex.S
@@ -31,7 +31,7 @@ SYM_FUNC_START(__arch_cpu_idle)
 1:	jr	ra
 SYM_FUNC_END(__arch_cpu_idle)
 
-SYM_FUNC_START(handle_vint)
+SYM_CODE_START(handle_vint)
 	BACKUP_T0T1
 	SAVE_ALL
 	la_abs	t1, __arch_cpu_idle
@@ -46,11 +46,11 @@ SYM_FUNC_START(handle_vint)
 	la_abs	t0, do_vint
 	jirl	ra, t0, 0
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_vint)
+SYM_CODE_END(handle_vint)
 
-SYM_FUNC_START(except_vec_cex)
+SYM_CODE_START(except_vec_cex)
 	b	cache_parity_error
-SYM_FUNC_END(except_vec_cex)
+SYM_CODE_END(except_vec_cex)
 
 	.macro	build_prep_badv
 	csrrd	t0, LOONGARCH_CSR_BADV
@@ -66,7 +66,7 @@ SYM_FUNC_END(except_vec_cex)
 
 	.macro	BUILD_HANDLER exception handler prep
 	.align	5
-	SYM_FUNC_START(handle_\exception)
+	SYM_CODE_START(handle_\exception)
 	666:
 	BACKUP_T0T1
 	SAVE_ALL
@@ -76,7 +76,7 @@ SYM_FUNC_END(except_vec_cex)
 	jirl	ra, t0, 0
 	668:
 	RESTORE_ALL_AND_RET
-	SYM_FUNC_END(handle_\exception)
+	SYM_CODE_END(handle_\exception)
 	SYM_DATA(unwind_hint_\exception, .word 668b - 666b)
 	.endm
 
@@ -93,7 +93,7 @@ SYM_FUNC_END(except_vec_cex)
 	BUILD_HANDLER watch watch none
 	BUILD_HANDLER reserved reserved none	/* others */
 
-SYM_FUNC_START(handle_sys)
+SYM_CODE_START(handle_sys)
 	la_abs	t0, handle_syscall
 	jr	t0
-SYM_FUNC_END(handle_sys)
+SYM_CODE_END(handle_sys)
diff --git a/arch/loongarch/mm/tlbex.S b/arch/loongarch/mm/tlbex.S
index ca17dd3a19153..d5d682f3d29f3 100644
--- a/arch/loongarch/mm/tlbex.S
+++ b/arch/loongarch/mm/tlbex.S
@@ -17,7 +17,7 @@
 #define PTRS_PER_PTE_BITS	(PAGE_SHIFT - 3)
 
 	.macro tlb_do_page_fault, write
-	SYM_FUNC_START(tlb_do_page_fault_\write)
+	SYM_CODE_START(tlb_do_page_fault_\write)
 	SAVE_ALL
 	csrrd		a2, LOONGARCH_CSR_BADV
 	move		a0, sp
@@ -25,13 +25,13 @@
 	li.w		a1, \write
 	bl		do_page_fault
 	RESTORE_ALL_AND_RET
-	SYM_FUNC_END(tlb_do_page_fault_\write)
+	SYM_CODE_END(tlb_do_page_fault_\write)
 	.endm
 
 	tlb_do_page_fault 0
 	tlb_do_page_fault 1
 
-SYM_FUNC_START(handle_tlb_protect)
+SYM_CODE_START(handle_tlb_protect)
 	BACKUP_T0T1
 	SAVE_ALL
 	move		a0, sp
@@ -41,9 +41,9 @@ SYM_FUNC_START(handle_tlb_protect)
 	la_abs		t0, do_page_fault
 	jirl		ra, t0, 0
 	RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_tlb_protect)
+SYM_CODE_END(handle_tlb_protect)
 
-SYM_FUNC_START(handle_tlb_load)
+SYM_CODE_START(handle_tlb_load)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -187,16 +187,16 @@ nopage_tlb_load:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_0
 	jr		t0
-SYM_FUNC_END(handle_tlb_load)
+SYM_CODE_END(handle_tlb_load)
 
-SYM_FUNC_START(handle_tlb_load_ptw)
+SYM_CODE_START(handle_tlb_load_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_0
 	jr		t0
-SYM_FUNC_END(handle_tlb_load_ptw)
+SYM_CODE_END(handle_tlb_load_ptw)
 
-SYM_FUNC_START(handle_tlb_store)
+SYM_CODE_START(handle_tlb_store)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -343,16 +343,16 @@ nopage_tlb_store:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_store)
+SYM_CODE_END(handle_tlb_store)
 
-SYM_FUNC_START(handle_tlb_store_ptw)
+SYM_CODE_START(handle_tlb_store_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_store_ptw)
+SYM_CODE_END(handle_tlb_store_ptw)
 
-SYM_FUNC_START(handle_tlb_modify)
+SYM_CODE_START(handle_tlb_modify)
 	csrwr		t0, EXCEPTION_KS0
 	csrwr		t1, EXCEPTION_KS1
 	csrwr		ra, EXCEPTION_KS2
@@ -497,16 +497,16 @@ nopage_tlb_modify:
 	csrrd		ra, EXCEPTION_KS2
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_modify)
+SYM_CODE_END(handle_tlb_modify)
 
-SYM_FUNC_START(handle_tlb_modify_ptw)
+SYM_CODE_START(handle_tlb_modify_ptw)
 	csrwr		t0, LOONGARCH_CSR_KS0
 	csrwr		t1, LOONGARCH_CSR_KS1
 	la_abs		t0, tlb_do_page_fault_1
 	jr		t0
-SYM_FUNC_END(handle_tlb_modify_ptw)
+SYM_CODE_END(handle_tlb_modify_ptw)
 
-SYM_FUNC_START(handle_tlb_refill)
+SYM_CODE_START(handle_tlb_refill)
 	csrwr		t0, LOONGARCH_CSR_TLBRSAVE
 	csrrd		t0, LOONGARCH_CSR_PGD
 	lddir		t0, t0, 3
@@ -521,4 +521,4 @@ SYM_FUNC_START(handle_tlb_refill)
 	tlbfill
 	csrrd		t0, LOONGARCH_CSR_TLBRSAVE
 	ertn
-SYM_FUNC_END(handle_tlb_refill)
+SYM_CODE_END(handle_tlb_refill)
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH AUTOSEL 6.5 41/52] LoongArch: Export symbol invalid_pud_table for modules building
       [not found] <20231029225441.789781-1-sashal@kernel.org>
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 40/52] LoongArch: Use SYM_CODE_* to annotate exception handlers Sasha Levin
@ 2023-10-29 22:53 ` Sasha Levin
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 42/52] LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage() Sasha Levin
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 43/52] LoongArch: Disable WUC for pgprot_writecombine() like ioremap_wc() Sasha Levin
  3 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2023-10-29 22:53 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Huacai Chen, Randy Dunlap, Tianrui Zhao, Sasha Levin, chenhuacai,
	maobibo, akpm, chenfeiyang, arnd, loongarch

From: Huacai Chen <chenhuacai@loongson.cn>

[ Upstream commit 449c2756c2323c9e32b2a2fa9c8b59ce91b5819d ]

Export symbol invalid_pud_table for modules building (such as the KVM
module) if 4-level page tables enabled. Otherwise we get:

ERROR: modpost: "invalid_pud_table" [arch/loongarch/kvm/kvm.ko] undefined!

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/loongarch/mm/init.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c
index 3b7d8129570b8..51c9a6c90a169 100644
--- a/arch/loongarch/mm/init.c
+++ b/arch/loongarch/mm/init.c
@@ -267,6 +267,7 @@ pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
 pgd_t invalid_pg_dir[_PTRS_PER_PGD] __page_aligned_bss;
 #ifndef __PAGETABLE_PUD_FOLDED
 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
+EXPORT_SYMBOL(invalid_pud_table);
 #endif
 #ifndef __PAGETABLE_PMD_FOLDED
 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH AUTOSEL 6.5 42/52] LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage()
       [not found] <20231029225441.789781-1-sashal@kernel.org>
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 40/52] LoongArch: Use SYM_CODE_* to annotate exception handlers Sasha Levin
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 41/52] LoongArch: Export symbol invalid_pud_table for modules building Sasha Levin
@ 2023-10-29 22:53 ` Sasha Levin
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 43/52] LoongArch: Disable WUC for pgprot_writecombine() like ioremap_wc() Sasha Levin
  3 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2023-10-29 22:53 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Huacai Chen, Deepak R Varma, Sasha Levin, chenhuacai, maobibo,
	akpm, chenfeiyang, arnd, loongarch

From: Huacai Chen <chenhuacai@loongson.cn>

[ Upstream commit 477a0ebec101359f49d92796e3b609857d564b52 ]

Replace kmap_atomic()/kunmap_atomic() calls with kmap_local_page()/
kunmap_local() in copy_user_highpage() which can be invoked from both
preemptible and atomic context [1].

[1] https://lore.kernel.org/all/20201029222652.302358281@linutronix.de/

Suggested-by: Deepak R Varma <drv@mailo.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/loongarch/mm/init.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c
index 51c9a6c90a169..d967d881c3fef 100644
--- a/arch/loongarch/mm/init.c
+++ b/arch/loongarch/mm/init.c
@@ -68,11 +68,11 @@ void copy_user_highpage(struct page *to, struct page *from,
 {
 	void *vfrom, *vto;
 
-	vto = kmap_atomic(to);
-	vfrom = kmap_atomic(from);
+	vfrom = kmap_local_page(from);
+	vto = kmap_local_page(to);
 	copy_page(vto, vfrom);
-	kunmap_atomic(vfrom);
-	kunmap_atomic(vto);
+	kunmap_local(vfrom);
+	kunmap_local(vto);
 	/* Make sure this page is cleared on other CPU's too before using it */
 	smp_wmb();
 }
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH AUTOSEL 6.5 43/52] LoongArch: Disable WUC for pgprot_writecombine() like ioremap_wc()
       [not found] <20231029225441.789781-1-sashal@kernel.org>
                   ` (2 preceding siblings ...)
  2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 42/52] LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage() Sasha Levin
@ 2023-10-29 22:53 ` Sasha Levin
  3 siblings, 0 replies; 4+ messages in thread
From: Sasha Levin @ 2023-10-29 22:53 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Icenowy Zheng, Huacai Chen, Sasha Levin, chenhuacai, kernel, akpm,
	bhe, rppt, willy, zhanghongchen, david, zhoubinbin, donmor3000,
	yangtiezhu, tangyouling, tglx, loongarch

From: Icenowy Zheng <uwu@icenowy.me>

[ Upstream commit 278be83601dd1725d4732241f066d528e160a39d ]

Currently the code disables WUC only disables it for ioremap_wc(), which
is only used when mapping writecombine pages like ioremap() (mapped to
the kernel space). But for VRAM mapped in TTM/GEM, it is mapped with a
crafted pgprot by the pgprot_writecombine() function, in which case WUC
isn't disabled now.

Disable WUC for pgprot_writecombine() (fallback to SUC) if needed, like
ioremap_wc().

This improves the AMDGPU driver's stability (solves some misrendering)
on Loongson-3A5000/3A6000 machines.

Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/loongarch/include/asm/io.h           |  5 ++---
 arch/loongarch/include/asm/pgtable-bits.h |  4 +++-
 arch/loongarch/kernel/setup.c             | 10 +++++-----
 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/arch/loongarch/include/asm/io.h b/arch/loongarch/include/asm/io.h
index 1c94102200407..0355b64e90ed0 100644
--- a/arch/loongarch/include/asm/io.h
+++ b/arch/loongarch/include/asm/io.h
@@ -54,10 +54,9 @@ static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
  * @offset:    bus address of the memory
  * @size:      size of the resource to map
  */
-extern pgprot_t pgprot_wc;
-
 #define ioremap_wc(offset, size)	\
-	ioremap_prot((offset), (size), pgprot_val(pgprot_wc))
+	ioremap_prot((offset), (size),	\
+		pgprot_val(wc_enabled ? PAGE_KERNEL_WUC : PAGE_KERNEL_SUC))
 
 #define ioremap_cache(offset, size)	\
 	ioremap_prot((offset), (size), pgprot_val(PAGE_KERNEL))
diff --git a/arch/loongarch/include/asm/pgtable-bits.h b/arch/loongarch/include/asm/pgtable-bits.h
index de46a6b1e9f11..7b9ac012cd090 100644
--- a/arch/loongarch/include/asm/pgtable-bits.h
+++ b/arch/loongarch/include/asm/pgtable-bits.h
@@ -105,13 +105,15 @@ static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 	return __pgprot(prot);
 }
 
+extern bool wc_enabled;
+
 #define pgprot_writecombine pgprot_writecombine
 
 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
 {
 	unsigned long prot = pgprot_val(_prot);
 
-	prot = (prot & ~_CACHE_MASK) | _CACHE_WUC;
+	prot = (prot & ~_CACHE_MASK) | (wc_enabled ? _CACHE_WUC : _CACHE_SUC);
 
 	return __pgprot(prot);
 }
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index 9d830ab4e3025..1351614042d4e 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -161,19 +161,19 @@ static void __init smbios_parse(void)
 }
 
 #ifdef CONFIG_ARCH_WRITECOMBINE
-pgprot_t pgprot_wc = PAGE_KERNEL_WUC;
+bool wc_enabled = true;
 #else
-pgprot_t pgprot_wc = PAGE_KERNEL_SUC;
+bool wc_enabled = false;
 #endif
 
-EXPORT_SYMBOL(pgprot_wc);
+EXPORT_SYMBOL(wc_enabled);
 
 static int __init setup_writecombine(char *p)
 {
 	if (!strcmp(p, "on"))
-		pgprot_wc = PAGE_KERNEL_WUC;
+		wc_enabled = true;
 	else if (!strcmp(p, "off"))
-		pgprot_wc = PAGE_KERNEL_SUC;
+		wc_enabled = false;
 	else
 		pr_warn("Unknown writecombine setting \"%s\".\n", p);
 
-- 
2.42.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

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Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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     [not found] <20231029225441.789781-1-sashal@kernel.org>
2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 40/52] LoongArch: Use SYM_CODE_* to annotate exception handlers Sasha Levin
2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 41/52] LoongArch: Export symbol invalid_pud_table for modules building Sasha Levin
2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 42/52] LoongArch: Replace kmap_atomic() with kmap_local_page() in copy_user_highpage() Sasha Levin
2023-10-29 22:53 ` [PATCH AUTOSEL 6.5 43/52] LoongArch: Disable WUC for pgprot_writecombine() like ioremap_wc() Sasha Levin

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