[PATCH 00/16] Generic infrastructure for unloading initramfs

[PATCH 00/16] Generic infrastructure for unloading initramfs

[Shea Levy]

This patch series extracts out code for unloading the initramfs that
was identical across 14 architectures, and moves those architectures
to the common code path. Additionally, RISC-V is newly moved to the
common code path.

In addition to reducing duplication, this allows us to bring future
improvements (such as generalizing existing "keep initrd" command line
options) to multiple architectures at once.

[PATCH 01/16] initrd: Add generic code path for common initrd unloading logic.

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 init/initramfs.c | 7 +++++++
 usr/Kconfig      | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/init/initramfs.c b/init/initramfs.c
index 7e99a0038942..de5ce873eb5a 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -526,6 +526,13 @@ extern unsigned long __initramfs_size;
 #include <linux/initrd.h>
 #include <linux/kexec.h>
 
+#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+       free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif
+
 static void __init free_initrd(void)
 {
 #ifdef CONFIG_KEXEC_CORE
diff --git a/usr/Kconfig b/usr/Kconfig
index 43658b8a975e..fd79d4d6fa26 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
 	default ".lzma" if RD_LZMA
 	default ".bz2"  if RD_BZIP2
 	default ""
+
+# Arches can select this for a generic initrd unloading codepath
+config INITRAMFS_GENERIC_UNLOAD
+	bool
-- 
2.16.2

Re: [PATCH 01/16] initrd: Add generic code path for common initrd unloading logic.

[LEROY Christophe]

Shea Levy <shea@shealevy.com> a =C3=A9crit=C2=A0:

> Signed-off-by: Shea Levy <shea@shealevy.com>
> ---
>  init/initramfs.c | 7 +++++++
>  usr/Kconfig      | 4 ++++
>  2 files changed, 11 insertions(+)
>
> diff --git a/init/initramfs.c b/init/initramfs.c
> index 7e99a0038942..de5ce873eb5a 100644
> --- a/init/initramfs.c
> +++ b/init/initramfs.c
> @@ -526,6 +526,13 @@ extern unsigned long __initramfs_size;
>  #include <linux/initrd.h>
>  #include <linux/kexec.h>
>
> +#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
> +void free_initrd_mem(unsigned long start, unsigned long end)
> +{
> +       free_reserved_area((void *)start, (void *)end, -1, "initrd");
> +}
> +#endif

In powerpc this was an __init function. Why not also put the generic=20=20
one=20in __init section ?

Christophe


> +
>  static void __init free_initrd(void)
>  {
>  #ifdef CONFIG_KEXEC_CORE
> diff --git a/usr/Kconfig b/usr/Kconfig
> index 43658b8a975e..fd79d4d6fa26 100644
> --- a/usr/Kconfig
> +++ b/usr/Kconfig
> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>  	default ".lzma" if RD_LZMA
>  	default ".bz2"  if RD_BZIP2
>  	default ""
> +
> +# Arches can select this for a generic initrd unloading codepath
> +config INITRAMFS_GENERIC_UNLOAD
> +	bool
> --
> 2.16.2

Re: [PATCH 01/16] initrd: Add generic code path for common initrd unloading logic.

[Shea Levy]

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Hi Christophe,

LEROY Christophe <christophe.leroy@c-s.fr> writes:

> Shea Levy <shea@shealevy.com> a écrit :
>
>> Signed-off-by: Shea Levy <shea@shealevy.com>
>> ---
>>  init/initramfs.c | 7 +++++++
>>  usr/Kconfig      | 4 ++++
>>  2 files changed, 11 insertions(+)
>>
>> diff --git a/init/initramfs.c b/init/initramfs.c
>> index 7e99a0038942..de5ce873eb5a 100644
>> --- a/init/initramfs.c
>> +++ b/init/initramfs.c
>> @@ -526,6 +526,13 @@ extern unsigned long __initramfs_size;
>>  #include <linux/initrd.h>
>>  #include <linux/kexec.h>
>>
>> +#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
>> +void free_initrd_mem(unsigned long start, unsigned long end)
>> +{
>> +       free_reserved_area((void *)start, (void *)end, -1, "initrd");
>> +}
>> +#endif
>
> In powerpc this was an __init function. Why not also put the generic  
> one in __init section ?
>

v2 series sent, thanks!

>
> Christophe
>
>
>> +
>>  static void __init free_initrd(void)
>>  {
>>  #ifdef CONFIG_KEXEC_CORE
>> diff --git a/usr/Kconfig b/usr/Kconfig
>> index 43658b8a975e..fd79d4d6fa26 100644
>> --- a/usr/Kconfig
>> +++ b/usr/Kconfig
>> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>>  	default ".lzma" if RD_LZMA
>>  	default ".bz2"  if RD_BZIP2
>>  	default ""
>> +
>> +# Arches can select this for a generic initrd unloading codepath
>> +config INITRAMFS_GENERIC_UNLOAD
>> +	bool
>> --
>> 2.16.2

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Re: [PATCH 01/16] initrd: Add generic code path for common initrd unloading logic.

[Christoph Hellwig]

> +#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
> +void free_initrd_mem(unsigned long start, unsigned long end)
> +{
> +       free_reserved_area((void *)start, (void *)end, -1, "initrd");
> +}
> +#endif

Given how trivial this is and how many architectures can use it I'd
reverse the polarity and add a CONFIG_HAVE_ARCH_FREE_INITRD_MEM
instead.

Re: [PATCH 01/16] initrd: Add generic code path for common initrd unloading logic.

[Geert Uytterhoeven]

On Wed, Mar 28, 2018 at 2:04 PM, Christoph Hellwig <hch@infradead.org> wrote:
>> +#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
>> +void free_initrd_mem(unsigned long start, unsigned long end)
>> +{
>> +       free_reserved_area((void *)start, (void *)end, -1, "initrd");
>> +}
>> +#endif
>
> Given how trivial this is and how many architectures can use it I'd
> reverse the polarity and add a CONFIG_HAVE_ARCH_FREE_INITRD_MEM
> instead.

And while adding "special" functionality to the generic version, more and more
users of CONFIG_HAVE_ARCH_FREE_INITRD_MEM will be removed.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH 02/16] riscv: Use INITRAMFS_GENERIC_UNLOAD.

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/riscv/Kconfig   | 1 +
 arch/riscv/mm/init.c | 6 ------
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c22ebe08e902..ab1b4cee84fc 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -37,6 +37,7 @@ config RISCV
 	select THREAD_INFO_IN_TASK
 	select RISCV_TIMER
 	select GENERIC_IRQ_MULTI_HANDLER
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	def_bool y
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c77df8142be2..36f83fe8a726 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -62,9 +62,3 @@ void free_initmem(void)
 {
 	free_initmem_default(0);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
-- 
2.16.2

[PATCH 03/16] alpha: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/alpha/Kconfig   | 1 +
 arch/alpha/mm/init.c | 8 --------
 2 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index e96adcbcab41..238d743ae8f2 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -27,6 +27,7 @@ config ALPHA
 	select ODD_RT_SIGACTION
 	select OLD_SIGSUSPEND
 	select CPU_NO_EFFICIENT_FFS if !ALPHA_EV67
+	select INITRAMFS_GENERIC_UNLOAD
 	help
 	  The Alpha is a 64-bit general-purpose processor designed and
 	  marketed by the Digital Equipment Corporation of blessed memory,
diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c
index 9d74520298ab..55f7c8efa962 100644
--- a/arch/alpha/mm/init.c
+++ b/arch/alpha/mm/init.c
@@ -291,11 +291,3 @@ free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void
-free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH 04/16] arc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/arc/Kconfig   | 1 +
 arch/arc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index d76bf4a83740..2844ce5b910c 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -44,6 +44,7 @@ config ARC
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZMA
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MIGHT_HAVE_PCI
 	bool
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index ba145065c579..7bcf23ab1756 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -229,10 +229,3 @@ void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH 05/16] c6x: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/c6x/Kconfig   | 1 +
 arch/c6x/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig
index c6b4dd1418b4..857f95f9a6a4 100644
--- a/arch/c6x/Kconfig
+++ b/arch/c6x/Kconfig
@@ -19,6 +19,7 @@ config C6X
 	select GENERIC_CLOCKEVENTS
 	select MODULES_USE_ELF_RELA
 	select ARCH_NO_COHERENT_DMA_MMAP
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	def_bool n
diff --git a/arch/c6x/mm/init.c b/arch/c6x/mm/init.c
index 4cc72b0d1c1d..a11cb657182a 100644
--- a/arch/c6x/mm/init.c
+++ b/arch/c6x/mm/init.c
@@ -66,13 +66,6 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __init free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH 06/16] frv: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/frv/Kconfig   |  1 +
 arch/frv/mm/init.c | 11 -----------
 2 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig
index af369b05fed5..5c104b800cb1 100644
--- a/arch/frv/Kconfig
+++ b/arch/frv/Kconfig
@@ -17,6 +17,7 @@ config FRV
 	select OLD_SIGACTION
 	select HAVE_DEBUG_STACKOVERFLOW
 	select ARCH_NO_COHERENT_DMA_MMAP
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/frv/mm/init.c b/arch/frv/mm/init.c
index cf464100e838..345edc4dc462 100644
--- a/arch/frv/mm/init.c
+++ b/arch/frv/mm/init.c
@@ -131,14 +131,3 @@ void free_initmem(void)
 	free_initmem_default(-1);
 #endif
 } /* end free_initmem() */
-
-/*****************************************************************************/
-/*
- * free the initial ramdisk memory
- */
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-} /* end free_initrd_mem() */
-#endif
-- 
2.16.2

[PATCH 07/16] h8300: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/h8300/Kconfig   | 1 +
 arch/h8300/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index 091d6d04b5e5..58c9b6b1df16 100644
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -24,6 +24,7 @@ config H8300
 	select HAVE_ARCH_HASH
 	select CPU_NO_EFFICIENT_FFS
 	select DMA_DIRECT_OPS
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/h8300/mm/init.c b/arch/h8300/mm/init.c
index 015287ac8ce8..37574332b202 100644
--- a/arch/h8300/mm/init.c
+++ b/arch/h8300/mm/init.c
@@ -102,13 +102,6 @@ void __init mem_init(void)
 }
 
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void
 free_initmem(void)
 {
-- 
2.16.2

[PATCH 08/16] m32r: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/m32r/Kconfig   |  1 +
 arch/m32r/mm/init.c | 11 -----------
 2 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index dd84ee194579..010a2b999181 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -21,6 +21,7 @@ config M32R
 	select CPU_NO_EFFICIENT_FFS
 	select DMA_DIRECT_OPS
 	select ARCH_NO_COHERENT_DMA_MMAP if !MMU
+	select INITRAMFS_GENERIC_UNLOAD
 
 config SBUS
 	bool
diff --git a/arch/m32r/mm/init.c b/arch/m32r/mm/init.c
index 93abc8c3a46e..e2b5f09209ee 100644
--- a/arch/m32r/mm/init.c
+++ b/arch/m32r/mm/init.c
@@ -139,14 +139,3 @@ void free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-/*======================================================================*
- * free_initrd_mem() :
- * orig : arch/sh/mm/init.c
- *======================================================================*/
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH 09/16] m68k: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/m68k/Kconfig   | 1 +
 arch/m68k/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 785612b576f7..47913a68529e 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -24,6 +24,7 @@ config M68K
 	select MODULES_USE_ELF_RELA
 	select OLD_SIGSUSPEND3
 	select OLD_SIGACTION
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
index e85acd131fa8..e20bef09258c 100644
--- a/arch/m68k/mm/init.c
+++ b/arch/m68k/mm/init.c
@@ -172,10 +172,3 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 	print_memmap();
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH 10/16] microblaze: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/microblaze/Kconfig   | 1 +
 arch/microblaze/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 3817a3e2146c..ef23e8410b4b 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -36,6 +36,7 @@ config MICROBLAZE
 	select TRACING_SUPPORT
 	select VIRT_TO_BUS
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 # Endianness selection
 choice
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index df6de7ccdc2e..ea058dfda222 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -187,13 +187,6 @@ void __init setup_memory(void)
 	paging_init();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH 11/16] nios2: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/nios2/Kconfig   | 1 +
 arch/nios2/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index 3d4ec88f1db1..d3b72d5c8967 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -19,6 +19,7 @@ config NIOS2
 	select SPARSE_IRQ
 	select USB_ARCH_HAS_HCD if USB_SUPPORT
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 config GENERIC_CSUM
 	def_bool y
diff --git a/arch/nios2/mm/init.c b/arch/nios2/mm/init.c
index c92fe4234009..3df75ff8c768 100644
--- a/arch/nios2/mm/init.c
+++ b/arch/nios2/mm/init.c
@@ -82,13 +82,6 @@ void __init mmu_init(void)
 	flush_tlb_all();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH 12/16] openrisc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/openrisc/Kconfig   | 1 +
 arch/openrisc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index dfb6a79ba7ff..0f8d2132baa5 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -36,6 +36,7 @@ config OPENRISC
 	select OMPIC if SMP
 	select ARCH_WANT_FRAME_POINTERS
 	select GENERIC_IRQ_MULTI_HANDLER
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
index 6972d5d6f23f..c1a3dcf9ad40 100644
--- a/arch/openrisc/mm/init.c
+++ b/arch/openrisc/mm/init.c
@@ -222,13 +222,6 @@ void __init mem_init(void)
 	return;
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH 13/16] parisc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/parisc/Kconfig   | 1 +
 arch/parisc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 9792d8cf4f56..7410c2094987 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -51,6 +51,7 @@ config PARISC
 	select GENERIC_CLOCKEVENTS
 	select ARCH_NO_COHERENT_DMA_MMAP
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 	help
 	  The PA-RISC microprocessor is designed by Hewlett-Packard and used
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index cab32ee824d2..3643399230f3 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -932,10 +932,3 @@ void flush_tlb_all(void)
 	spin_unlock(&sid_lock);
 }
 #endif
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH 14/16] powerpc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/powerpc/Kconfig  | 1 +
 arch/powerpc/mm/mem.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd07642..8cf384068e79 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -223,6 +223,7 @@ config PPC
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HAVE_IRQ_TIME_ACCOUNTING
+	select INITRAMFS_GENERIC_UNLOAD
 	select IRQ_DOMAIN
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
-- 
2.16.2

[PATCH 15/16] sh: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/sh/Kconfig   | 1 +
 arch/sh/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 97fe29316476..b6f80dad2152 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -50,6 +50,7 @@ config SUPERH
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
+	select INITRAMFS_GENERIC_UNLOAD
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
 	  and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index ce0bbaa7e404..7451459d0725 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -477,13 +477,6 @@ void free_initmem(void)
 	free_initmem_default(-1);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 		bool want_memblock)
-- 
2.16.2

[PATCH 16/16] um: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/um/Kconfig.common | 1 +
 arch/um/kernel/mem.c   | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index c68add8df3ae..1cb8a023938b 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -13,6 +13,7 @@ config UML
 	select GENERIC_CLOCKEVENTS
 	select HAVE_GCC_PLUGINS
 	select TTY # Needed for line.c
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	bool
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 3c0e470ea646..2d26eec92126 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -170,13 +170,6 @@ void free_initmem(void)
 {
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /* Allocate and free page tables. */
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
-- 
2.16.2

[PATCH v2 00/16] Generic infrastructure for unloading initramfs

[Shea Levy]

This patch series extracts out code for unloading the initramfs that
was identical across 14 architectures, and moves those architectures
to the common code path. Additionally, RISC-V is newly moved to the
common code path.

In addition to reducing duplication, this allows us to bring future
improvements (such as generalizing existing "keep initrd" command line
options) to multiple architectures at once.

v2: Mark generic free_initrd_mem __init.

[PATCH v2 01/16] initrd: Add generic code path for common initrd unloading logic.

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 init/initramfs.c | 7 +++++++
 usr/Kconfig      | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/init/initramfs.c b/init/initramfs.c
index 7e99a0038942..5f2e3dba4822 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -526,6 +526,13 @@ extern unsigned long __initramfs_size;
 #include <linux/initrd.h>
 #include <linux/kexec.h>
 
+#ifdef CONFIG_INITRAMFS_GENERIC_UNLOAD
+void __init free_initrd_mem(unsigned long start, unsigned long end)
+{
+       free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif
+
 static void __init free_initrd(void)
 {
 #ifdef CONFIG_KEXEC_CORE
diff --git a/usr/Kconfig b/usr/Kconfig
index 43658b8a975e..fd79d4d6fa26 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
 	default ".lzma" if RD_LZMA
 	default ".bz2"  if RD_BZIP2
 	default ""
+
+# Arches can select this for a generic initrd unloading codepath
+config INITRAMFS_GENERIC_UNLOAD
+	bool
-- 
2.16.2

[PATCH v2 02/16] riscv: Use INITRAMFS_GENERIC_UNLOAD.

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/riscv/Kconfig   | 1 +
 arch/riscv/mm/init.c | 6 ------
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c22ebe08e902..ab1b4cee84fc 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -37,6 +37,7 @@ config RISCV
 	select THREAD_INFO_IN_TASK
 	select RISCV_TIMER
 	select GENERIC_IRQ_MULTI_HANDLER
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	def_bool y
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c77df8142be2..36f83fe8a726 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -62,9 +62,3 @@ void free_initmem(void)
 {
 	free_initmem_default(0);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
-- 
2.16.2

Re: [PATCH v2 02/16] riscv: Use INITRAMFS_GENERIC_UNLOAD.

[Palmer Dabbelt]

On Sun, 25 Mar 2018 15:18:39 PDT (-0700), shea@shealevy.com wrote:
> Signed-off-by: Shea Levy <shea@shealevy.com>
> ---
>  arch/riscv/Kconfig   | 1 +
>  arch/riscv/mm/init.c | 6 ------
>  2 files changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index c22ebe08e902..ab1b4cee84fc 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -37,6 +37,7 @@ config RISCV
>  	select THREAD_INFO_IN_TASK
>  	select RISCV_TIMER
>  	select GENERIC_IRQ_MULTI_HANDLER
> +	select INITRAMFS_GENERIC_UNLOAD
>
>  config MMU
>  	def_bool y
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index c77df8142be2..36f83fe8a726 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -62,9 +62,3 @@ void free_initmem(void)
>  {
>  	free_initmem_default(0);
>  }
> -
> -#ifdef CONFIG_BLK_DEV_INITRD
> -void free_initrd_mem(unsigned long start, unsigned long end)
> -{
> -}
> -#endif /* CONFIG_BLK_DEV_INITRD */

I haven't looked through the rest of the patch set, but this is a pretty 
trivial change so feel free to add a 

Reviewed-By: Palmer Dabbelt <palmer@sifive.com>

if you'd like.  If you'd like it merged through my tree then just say 
something!

Re: [PATCH v2 02/16] riscv: Use INITRAMFS_GENERIC_UNLOAD.

[Shea Levy]

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Hi Palmer,

Palmer Dabbelt <palmer@sifive.com> writes:

> On Sun, 25 Mar 2018 15:18:39 PDT (-0700), shea@shealevy.com wrote:
>> Signed-off-by: Shea Levy <shea@shealevy.com>
>> ---
>>  arch/riscv/Kconfig   | 1 +
>>  arch/riscv/mm/init.c | 6 ------
>>  2 files changed, 1 insertion(+), 6 deletions(-)
>>
>> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> index c22ebe08e902..ab1b4cee84fc 100644
>> --- a/arch/riscv/Kconfig
>> +++ b/arch/riscv/Kconfig
>> @@ -37,6 +37,7 @@ config RISCV
>>  	select THREAD_INFO_IN_TASK
>>  	select RISCV_TIMER
>>  	select GENERIC_IRQ_MULTI_HANDLER
>> +	select INITRAMFS_GENERIC_UNLOAD
>>
>>  config MMU
>>  	def_bool y
>> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
>> index c77df8142be2..36f83fe8a726 100644
>> --- a/arch/riscv/mm/init.c
>> +++ b/arch/riscv/mm/init.c
>> @@ -62,9 +62,3 @@ void free_initmem(void)
>>  {
>>  	free_initmem_default(0);
>>  }
>> -
>> -#ifdef CONFIG_BLK_DEV_INITRD
>> -void free_initrd_mem(unsigned long start, unsigned long end)
>> -{
>> -}
>> -#endif /* CONFIG_BLK_DEV_INITRD */
>
> I haven't looked through the rest of the patch set, but this is a pretty 
> trivial change so feel free to add a 
>
> Reviewed-By: Palmer Dabbelt <palmer@sifive.com>
>
> if you'd like.  If you'd like it merged through my tree then just say 
> something!

I'm not sure how these cross-cutting changes go, if you can take the
series through your tree that'd be great!

Thanks,
Shea

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[PATCH v2 03/16] alpha: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/alpha/Kconfig   | 1 +
 arch/alpha/mm/init.c | 8 --------
 2 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index e96adcbcab41..238d743ae8f2 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -27,6 +27,7 @@ config ALPHA
 	select ODD_RT_SIGACTION
 	select OLD_SIGSUSPEND
 	select CPU_NO_EFFICIENT_FFS if !ALPHA_EV67
+	select INITRAMFS_GENERIC_UNLOAD
 	help
 	  The Alpha is a 64-bit general-purpose processor designed and
 	  marketed by the Digital Equipment Corporation of blessed memory,
diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c
index 9d74520298ab..55f7c8efa962 100644
--- a/arch/alpha/mm/init.c
+++ b/arch/alpha/mm/init.c
@@ -291,11 +291,3 @@ free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void
-free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH v2 04/16] arc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/arc/Kconfig   | 1 +
 arch/arc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index d76bf4a83740..2844ce5b910c 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -44,6 +44,7 @@ config ARC
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZMA
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MIGHT_HAVE_PCI
 	bool
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index ba145065c579..7bcf23ab1756 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -229,10 +229,3 @@ void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH v2 05/16] c6x: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/c6x/Kconfig   | 1 +
 arch/c6x/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig
index c6b4dd1418b4..857f95f9a6a4 100644
--- a/arch/c6x/Kconfig
+++ b/arch/c6x/Kconfig
@@ -19,6 +19,7 @@ config C6X
 	select GENERIC_CLOCKEVENTS
 	select MODULES_USE_ELF_RELA
 	select ARCH_NO_COHERENT_DMA_MMAP
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	def_bool n
diff --git a/arch/c6x/mm/init.c b/arch/c6x/mm/init.c
index 4cc72b0d1c1d..a11cb657182a 100644
--- a/arch/c6x/mm/init.c
+++ b/arch/c6x/mm/init.c
@@ -66,13 +66,6 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __init free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH v2 06/16] frv: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/frv/Kconfig   |  1 +
 arch/frv/mm/init.c | 11 -----------
 2 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig
index af369b05fed5..5c104b800cb1 100644
--- a/arch/frv/Kconfig
+++ b/arch/frv/Kconfig
@@ -17,6 +17,7 @@ config FRV
 	select OLD_SIGACTION
 	select HAVE_DEBUG_STACKOVERFLOW
 	select ARCH_NO_COHERENT_DMA_MMAP
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/frv/mm/init.c b/arch/frv/mm/init.c
index cf464100e838..345edc4dc462 100644
--- a/arch/frv/mm/init.c
+++ b/arch/frv/mm/init.c
@@ -131,14 +131,3 @@ void free_initmem(void)
 	free_initmem_default(-1);
 #endif
 } /* end free_initmem() */
-
-/*****************************************************************************/
-/*
- * free the initial ramdisk memory
- */
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-} /* end free_initrd_mem() */
-#endif
-- 
2.16.2

[PATCH v2 07/16] h8300: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/h8300/Kconfig   | 1 +
 arch/h8300/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index 091d6d04b5e5..58c9b6b1df16 100644
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -24,6 +24,7 @@ config H8300
 	select HAVE_ARCH_HASH
 	select CPU_NO_EFFICIENT_FFS
 	select DMA_DIRECT_OPS
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/h8300/mm/init.c b/arch/h8300/mm/init.c
index 015287ac8ce8..37574332b202 100644
--- a/arch/h8300/mm/init.c
+++ b/arch/h8300/mm/init.c
@@ -102,13 +102,6 @@ void __init mem_init(void)
 }
 
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void
 free_initmem(void)
 {
-- 
2.16.2

[PATCH v2 08/16] m32r: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/m32r/Kconfig   |  1 +
 arch/m32r/mm/init.c | 11 -----------
 2 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index dd84ee194579..010a2b999181 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -21,6 +21,7 @@ config M32R
 	select CPU_NO_EFFICIENT_FFS
 	select DMA_DIRECT_OPS
 	select ARCH_NO_COHERENT_DMA_MMAP if !MMU
+	select INITRAMFS_GENERIC_UNLOAD
 
 config SBUS
 	bool
diff --git a/arch/m32r/mm/init.c b/arch/m32r/mm/init.c
index 93abc8c3a46e..e2b5f09209ee 100644
--- a/arch/m32r/mm/init.c
+++ b/arch/m32r/mm/init.c
@@ -139,14 +139,3 @@ void free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-/*======================================================================*
- * free_initrd_mem() :
- * orig : arch/sh/mm/init.c
- *======================================================================*/
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH v2 09/16] m68k: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/m68k/Kconfig   | 1 +
 arch/m68k/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 785612b576f7..47913a68529e 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -24,6 +24,7 @@ config M68K
 	select MODULES_USE_ELF_RELA
 	select OLD_SIGSUSPEND3
 	select OLD_SIGACTION
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
index e85acd131fa8..e20bef09258c 100644
--- a/arch/m68k/mm/init.c
+++ b/arch/m68k/mm/init.c
@@ -172,10 +172,3 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 	print_memmap();
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH v2 10/16] microblaze: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/microblaze/Kconfig   | 1 +
 arch/microblaze/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 3817a3e2146c..ef23e8410b4b 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -36,6 +36,7 @@ config MICROBLAZE
 	select TRACING_SUPPORT
 	select VIRT_TO_BUS
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 # Endianness selection
 choice
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index df6de7ccdc2e..ea058dfda222 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -187,13 +187,6 @@ void __init setup_memory(void)
 	paging_init();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH v2 11/16] nios2: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/nios2/Kconfig   | 1 +
 arch/nios2/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index 3d4ec88f1db1..d3b72d5c8967 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -19,6 +19,7 @@ config NIOS2
 	select SPARSE_IRQ
 	select USB_ARCH_HAS_HCD if USB_SUPPORT
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 config GENERIC_CSUM
 	def_bool y
diff --git a/arch/nios2/mm/init.c b/arch/nios2/mm/init.c
index c92fe4234009..3df75ff8c768 100644
--- a/arch/nios2/mm/init.c
+++ b/arch/nios2/mm/init.c
@@ -82,13 +82,6 @@ void __init mmu_init(void)
 	flush_tlb_all();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH v2 12/16] openrisc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/openrisc/Kconfig   | 1 +
 arch/openrisc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index dfb6a79ba7ff..0f8d2132baa5 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -36,6 +36,7 @@ config OPENRISC
 	select OMPIC if SMP
 	select ARCH_WANT_FRAME_POINTERS
 	select GENERIC_IRQ_MULTI_HANDLER
+	select INITRAMFS_GENERIC_UNLOAD
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
index 6972d5d6f23f..c1a3dcf9ad40 100644
--- a/arch/openrisc/mm/init.c
+++ b/arch/openrisc/mm/init.c
@@ -222,13 +222,6 @@ void __init mem_init(void)
 	return;
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
-- 
2.16.2

[PATCH v2 13/16] parisc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/parisc/Kconfig   | 1 +
 arch/parisc/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 9792d8cf4f56..7410c2094987 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -51,6 +51,7 @@ config PARISC
 	select GENERIC_CLOCKEVENTS
 	select ARCH_NO_COHERENT_DMA_MMAP
 	select CPU_NO_EFFICIENT_FFS
+	select INITRAMFS_GENERIC_UNLOAD
 
 	help
 	  The PA-RISC microprocessor is designed by Hewlett-Packard and used
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index cab32ee824d2..3643399230f3 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -932,10 +932,3 @@ void flush_tlb_all(void)
 	spin_unlock(&sid_lock);
 }
 #endif
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-- 
2.16.2

[PATCH v2 14/16] powerpc: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/powerpc/Kconfig  | 1 +
 arch/powerpc/mm/mem.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd07642..8cf384068e79 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -223,6 +223,7 @@ config PPC
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HAVE_IRQ_TIME_ACCOUNTING
+	select INITRAMFS_GENERIC_UNLOAD
 	select IRQ_DOMAIN
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
-- 
2.16.2

[PATCH v2 15/16] sh: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/sh/Kconfig   | 1 +
 arch/sh/mm/init.c | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 97fe29316476..b6f80dad2152 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -50,6 +50,7 @@ config SUPERH
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
+	select INITRAMFS_GENERIC_UNLOAD
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
 	  and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index ce0bbaa7e404..7451459d0725 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -477,13 +477,6 @@ void free_initmem(void)
 	free_initmem_default(-1);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 		bool want_memblock)
-- 
2.16.2

[PATCH v2 16/16] um: Use INITRAMFS_GENERIC_UNLOAD

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/um/Kconfig.common | 1 +
 arch/um/kernel/mem.c   | 7 -------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common
index c68add8df3ae..1cb8a023938b 100644
--- a/arch/um/Kconfig.common
+++ b/arch/um/Kconfig.common
@@ -13,6 +13,7 @@ config UML
 	select GENERIC_CLOCKEVENTS
 	select HAVE_GCC_PLUGINS
 	select TTY # Needed for line.c
+	select INITRAMFS_GENERIC_UNLOAD
 
 config MMU
 	bool
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 3c0e470ea646..2d26eec92126 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -170,13 +170,6 @@ void free_initmem(void)
 {
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /* Allocate and free page tables. */
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
-- 
2.16.2

[PATCH] Extract initrd free logic from arch-specific code.

[Shea Levy]

Now only those architectures that have custom initrd free requirements
need to define free_initrd_mem.

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/alpha/mm/init.c      |  8 --------
 arch/arc/mm/init.c        |  7 -------
 arch/arm/Kconfig          |  1 +
 arch/arm64/Kconfig        |  1 +
 arch/blackfin/Kconfig     |  1 +
 arch/c6x/mm/init.c        |  7 -------
 arch/cris/Kconfig         |  1 +
 arch/frv/mm/init.c        | 11 -----------
 arch/h8300/mm/init.c      |  7 -------
 arch/hexagon/Kconfig      |  1 +
 arch/ia64/Kconfig         |  1 +
 arch/m32r/Kconfig         |  1 +
 arch/m32r/mm/init.c       | 11 -----------
 arch/m68k/mm/init.c       |  7 -------
 arch/metag/Kconfig        |  1 +
 arch/microblaze/mm/init.c |  7 -------
 arch/mips/Kconfig         |  1 +
 arch/mn10300/Kconfig      |  1 +
 arch/nios2/mm/init.c      |  7 -------
 arch/openrisc/mm/init.c   |  7 -------
 arch/parisc/mm/init.c     |  7 -------
 arch/powerpc/mm/mem.c     |  7 -------
 arch/riscv/mm/init.c      |  6 ------
 arch/s390/Kconfig         |  1 +
 arch/score/Kconfig        |  1 +
 arch/sh/mm/init.c         |  7 -------
 arch/sparc/Kconfig        |  1 +
 arch/tile/Kconfig         |  1 +
 arch/um/kernel/mem.c      |  7 -------
 arch/unicore32/Kconfig    |  1 +
 arch/x86/Kconfig          |  1 +
 arch/xtensa/Kconfig       |  1 +
 init/initramfs.c          |  7 +++++++
 usr/Kconfig               |  4 ++++
 34 files changed, 28 insertions(+), 113 deletions(-)

diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c
index 9d74520298ab..55f7c8efa962 100644
--- a/arch/alpha/mm/init.c
+++ b/arch/alpha/mm/init.c
@@ -291,11 +291,3 @@ free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void
-free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
index ba145065c579..7bcf23ab1756 100644
--- a/arch/arc/mm/init.c
+++ b/arch/arc/mm/init.c
@@ -229,10 +229,3 @@ void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3f972e83909b..19d1c5594e2d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -47,6 +47,7 @@ config ARM
 	select HARDIRQS_SW_RESEND
 	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
 	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
 	select HAVE_ARCH_MMAP_RND_BITS if MMU
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index cb03e93f03cf..de93620870af 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -85,6 +85,7 @@ config ARM64
 	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_BITREVERSE
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_HUGE_VMAP
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index d9c2866ba618..6c6dae9fe894 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -15,6 +15,7 @@ config BLACKFIN
 	def_bool y
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_FUNCTION_GRAPH_TRACER
diff --git a/arch/c6x/mm/init.c b/arch/c6x/mm/init.c
index 4cc72b0d1c1d..a11cb657182a 100644
--- a/arch/c6x/mm/init.c
+++ b/arch/c6x/mm/init.c
@@ -66,13 +66,6 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __init free_initmem(void)
 {
 	free_initmem_default(-1);
diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig
index cd5a0865c97f..5425f77e5664 100644
--- a/arch/cris/Kconfig
+++ b/arch/cris/Kconfig
@@ -76,6 +76,7 @@ config CRIS
 	select HAVE_DEBUG_BUGVERBOSE if ETRAX_ARCH_V32
 	select HAVE_NMI
 	select DMA_DIRECT_OPS if PCI
+	select HAVE_ARCH_FREE_INITRD_MEM
 
 config HZ
 	int
diff --git a/arch/frv/mm/init.c b/arch/frv/mm/init.c
index cf464100e838..345edc4dc462 100644
--- a/arch/frv/mm/init.c
+++ b/arch/frv/mm/init.c
@@ -131,14 +131,3 @@ void free_initmem(void)
 	free_initmem_default(-1);
 #endif
 } /* end free_initmem() */
-
-/*****************************************************************************/
-/*
- * free the initial ramdisk memory
- */
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-} /* end free_initrd_mem() */
-#endif
diff --git a/arch/h8300/mm/init.c b/arch/h8300/mm/init.c
index 015287ac8ce8..37574332b202 100644
--- a/arch/h8300/mm/init.c
+++ b/arch/h8300/mm/init.c
@@ -102,13 +102,6 @@ void __init mem_init(void)
 }
 
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void
 free_initmem(void)
 {
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index 76d2f20d525e..69a16cd2e253 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -17,6 +17,7 @@ config HEXAGON
 	# GENERIC_ALLOCATOR is used by dma_alloc_coherent()
 	select GENERIC_ALLOCATOR
 	select GENERIC_IRQ_SHOW
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK
 	select NO_IOPORT_MAP
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index bbe12a038d21..366ef1dd3cd4 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -28,6 +28,7 @@ config IA64
 	select HAVE_DYNAMIC_FTRACE if (!ITANIUM)
 	select HAVE_FUNCTION_TRACER
 	select TTY
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_DMA_API_DEBUG
 	select HAVE_MEMBLOCK
diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index dd84ee194579..9e41bdff45c3 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -21,6 +21,7 @@ config M32R
 	select CPU_NO_EFFICIENT_FFS
 	select DMA_DIRECT_OPS
 	select ARCH_NO_COHERENT_DMA_MMAP if !MMU
+	select HAVE_ARCH_FREE_INITRD_MEM
 
 config SBUS
 	bool
diff --git a/arch/m32r/mm/init.c b/arch/m32r/mm/init.c
index 93abc8c3a46e..e2b5f09209ee 100644
--- a/arch/m32r/mm/init.c
+++ b/arch/m32r/mm/init.c
@@ -139,14 +139,3 @@ void free_initmem(void)
 {
 	free_initmem_default(-1);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-/*======================================================================*
- * free_initrd_mem() :
- * orig : arch/sh/mm/init.c
- *======================================================================*/
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
index e85acd131fa8..e20bef09258c 100644
--- a/arch/m68k/mm/init.c
+++ b/arch/m68k/mm/init.c
@@ -172,10 +172,3 @@ void __init mem_init(void)
 	mem_init_print_info(NULL);
 	print_memmap();
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
diff --git a/arch/metag/Kconfig b/arch/metag/Kconfig
index c7b62a339539..5be7f1693b1b 100644
--- a/arch/metag/Kconfig
+++ b/arch/metag/Kconfig
@@ -7,6 +7,7 @@ config METAG
 	select GENERIC_IRQ_SHOW
 	select GENERIC_SMP_IDLE_THREAD
 	select HAVE_64BIT_ALIGNED_ACCESS
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_C_RECORDMCOUNT
 	select HAVE_DEBUG_KMEMLEAK
diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c
index df6de7ccdc2e..ea058dfda222 100644
--- a/arch/microblaze/mm/init.c
+++ b/arch/microblaze/mm/init.c
@@ -187,13 +187,6 @@ void __init setup_memory(void)
 	paging_init();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 8128c3b68d6b..c033cd1e0c52 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -27,6 +27,7 @@ config MIPS
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select HANDLE_DOMAIN_IRQ
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_MMAP_RND_BITS if MMU
diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig
index e9d8d60bd28b..5aa4f1aa309f 100644
--- a/arch/mn10300/Kconfig
+++ b/arch/mn10300/Kconfig
@@ -6,6 +6,7 @@ config MN10300
 	select HAVE_UID16
 	select GENERIC_IRQ_SHOW
 	select ARCH_WANT_IPC_PARSE_VERSION
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_ARCH_KGDB
 	select GENERIC_ATOMIC64
diff --git a/arch/nios2/mm/init.c b/arch/nios2/mm/init.c
index c92fe4234009..3df75ff8c768 100644
--- a/arch/nios2/mm/init.c
+++ b/arch/nios2/mm/init.c
@@ -82,13 +82,6 @@ void __init mmu_init(void)
 	flush_tlb_all();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
index 6972d5d6f23f..c1a3dcf9ad40 100644
--- a/arch/openrisc/mm/init.c
+++ b/arch/openrisc/mm/init.c
@@ -222,13 +222,6 @@ void __init mem_init(void)
 	return;
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 void free_initmem(void)
 {
 	free_initmem_default(-1);
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index cab32ee824d2..3643399230f3 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -932,10 +932,3 @@ void flush_tlb_all(void)
 	spin_unlock(&sid_lock);
 }
 #endif
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index c77df8142be2..36f83fe8a726 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -62,9 +62,3 @@ void free_initmem(void)
 {
 	free_initmem_default(0);
 }
-
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index eaee7087886f..94a9879f1ea8 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -125,6 +125,7 @@ config S390
 	select GENERIC_TIME_VSYSCALL
 	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
 	select HAVE_ARCH_AUDITSYSCALL
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_JUMP_LABEL
 	select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
 	select HAVE_ARCH_SECCOMP_FILTER
diff --git a/arch/score/Kconfig b/arch/score/Kconfig
index d881f99c9ddd..2beff03b2429 100644
--- a/arch/score/Kconfig
+++ b/arch/score/Kconfig
@@ -16,6 +16,7 @@ config SCORE
 	select MODULES_USE_ELF_REL
 	select CLONE_BACKWARDS
 	select CPU_NO_EFFICIENT_FFS
+	select HAVE_ARCH_FREE_INITRD_MEM
 
 choice
 	prompt "System type"
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index ce0bbaa7e404..7451459d0725 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -477,13 +477,6 @@ void free_initmem(void)
 	free_initmem_default(-1);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 #ifdef CONFIG_MEMORY_HOTPLUG
 int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 		bool want_memblock)
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 8767e45f1b2b..06d543e35caf 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -18,6 +18,7 @@ config SPARC
 	select OF_PROMTREE
 	select HAVE_IDE
 	select HAVE_OPROFILE
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_KGDB if !SMP || SPARC64
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_EXIT_THREAD
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index ef9d403cbbe4..7fb36c15762c 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -16,6 +16,7 @@ config TILE
 	select GENERIC_PENDING_IRQ if SMP
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_SECCOMP_FILTER
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_CONTEXT_TRACKING
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 3c0e470ea646..2d26eec92126 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -170,13 +170,6 @@ void free_initmem(void)
 {
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /* Allocate and free page tables. */
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
index 462e59a7ae78..4da24cf467de 100644
--- a/arch/unicore32/Kconfig
+++ b/arch/unicore32/Kconfig
@@ -4,6 +4,7 @@ config UNICORE32
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
 	select ARCH_MIGHT_HAVE_PC_PARPORT
 	select ARCH_MIGHT_HAVE_PC_SERIO
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_MEMBLOCK
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_KERNEL_GZIP
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0fa71a78ec99..51ce64e6d848 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -111,6 +111,7 @@ config X86
 	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KASAN			if X86_64
 	select HAVE_ARCH_KGDB
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index c921e8bccdc8..01a4a0e42118 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -16,6 +16,7 @@ config XTENSA
 	select GENERIC_PCI_IOMAP
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_STRNCPY_FROM_USER if KASAN
+	select HAVE_ARCH_FREE_INITRD_MEM
 	select HAVE_ARCH_KASAN if MMU
 	select HAVE_CC_STACKPROTECTOR
 	select HAVE_DEBUG_KMEMLEAK
diff --git a/init/initramfs.c b/init/initramfs.c
index 7e99a0038942..d319058eb464 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -526,6 +526,13 @@ extern unsigned long __initramfs_size;
 #include <linux/initrd.h>
 #include <linux/kexec.h>
 
+#ifndef CONFIG_HAVE_ARCH_FREE_INITRD_MEM
+void __init free_initrd_mem(unsigned long start, unsigned long end)
+{
+       free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif
+
 static void __init free_initrd(void)
 {
 #ifdef CONFIG_KEXEC_CORE
diff --git a/usr/Kconfig b/usr/Kconfig
index 43658b8a975e..7a94f6df39bf 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
 	default ".lzma" if RD_LZMA
 	default ".bz2"  if RD_BZIP2
 	default ""
+
+config HAVE_ARCH_FREE_INITRD_MEM
+	bool
+	default n
-- 
2.16.2

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Rob Landley]

On 03/28/2018 10:26 AM, Shea Levy wrote:
> Now only those architectures that have custom initrd free requirements
> need to define free_initrd_mem.
...
> --- a/arch/arc/mm/init.c
> +++ b/arch/arc/mm/init.c
> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>  {
>  	free_initmem_default(-1);
>  }
> -
> -#ifdef CONFIG_BLK_DEV_INITRD
> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> -{
> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
> -}
> -#endif
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 3f972e83909b..19d1c5594e2d 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -47,6 +47,7 @@ config ARM
>  	select HARDIRQS_SW_RESEND
>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> +	select HAVE_ARCH_FREE_INITRD_MEM
>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>  	select HAVE_ARCH_MMAP_RND_BITS if MMU

Isn't this why weak symbols were invented?

Confused,

Rob

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Shea Levy]

[-- Attachment #1: Type: text/plain, Size: 1411 bytes --]

Hi Rob,

Rob Landley <rob@landley.net> writes:

> On 03/28/2018 10:26 AM, Shea Levy wrote:
>> Now only those architectures that have custom initrd free requirements
>> need to define free_initrd_mem.
> ...
>> --- a/arch/arc/mm/init.c
>> +++ b/arch/arc/mm/init.c
>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>>  {
>>  	free_initmem_default(-1);
>>  }
>> -
>> -#ifdef CONFIG_BLK_DEV_INITRD
>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
>> -{
>> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
>> -}
>> -#endif
>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> index 3f972e83909b..19d1c5594e2d 100644
>> --- a/arch/arm/Kconfig
>> +++ b/arch/arm/Kconfig
>> @@ -47,6 +47,7 @@ config ARM
>>  	select HARDIRQS_SW_RESEND
>>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
>> +	select HAVE_ARCH_FREE_INITRD_MEM
>>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>>  	select HAVE_ARCH_MMAP_RND_BITS if MMU
>
> Isn't this why weak symbols were invented?
>

This approach was suggested by Christoph Hellwig upthread, and seems to
have some precedent elsewhere (e.g. strncasecmp), but I agree weak
symbols seem appropriate here. I'm happy to implement either approach!

>
> Confused,
>
> Rob

Thanks,
Shea

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> On 03/28/2018 10:26 AM, Shea Levy wrote:
> > Now only those architectures that have custom initrd free requirements
> > need to define free_initrd_mem.
> ...
> > --- a/arch/arc/mm/init.c
> > +++ b/arch/arc/mm/init.c
> > @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >  {
> >  	free_initmem_default(-1);
> >  }
> > -
> > -#ifdef CONFIG_BLK_DEV_INITRD
> > -void __init free_initrd_mem(unsigned long start, unsigned long end)
> > -{
> > -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
> > -}
> > -#endif
> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > index 3f972e83909b..19d1c5594e2d 100644
> > --- a/arch/arm/Kconfig
> > +++ b/arch/arm/Kconfig
> > @@ -47,6 +47,7 @@ config ARM
> >  	select HARDIRQS_SW_RESEND
> >  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> > +	select HAVE_ARCH_FREE_INITRD_MEM
> >  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >  	select HAVE_ARCH_MMAP_RND_BITS if MMU
> 
> Isn't this why weak symbols were invented?

Weak symbols means that we end up with both the weakly-referenced code
and the arch code in the kernel image.  That's fine if the weak code
is small.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Rob Landley]

On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
>> On 03/28/2018 10:26 AM, Shea Levy wrote:
>>> Now only those architectures that have custom initrd free requirements
>>> need to define free_initrd_mem.
>> ...
>>> --- a/arch/arc/mm/init.c
>>> +++ b/arch/arc/mm/init.c
>>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>>>  {
>>>  	free_initmem_default(-1);
>>>  }
>>> -
>>> -#ifdef CONFIG_BLK_DEV_INITRD
>>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
>>> -{
>>> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
>>> -}
>>> -#endif
>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>>> index 3f972e83909b..19d1c5594e2d 100644
>>> --- a/arch/arm/Kconfig
>>> +++ b/arch/arm/Kconfig
>>> @@ -47,6 +47,7 @@ config ARM
>>>  	select HARDIRQS_SW_RESEND
>>>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>>>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
>>> +	select HAVE_ARCH_FREE_INITRD_MEM
>>>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>>>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>>>  	select HAVE_ARCH_MMAP_RND_BITS if MMU
>>
>> Isn't this why weak symbols were invented?
> 
> Weak symbols means that we end up with both the weakly-referenced code
> and the arch code in the kernel image.  That's fine if the weak code
> is small.

The kernel's been able to build with link time garbage collection since 2016:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d

Wouldn't that remove the unused one?

Rob

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> 
> 
> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
> >>> Now only those architectures that have custom initrd free requirements
> >>> need to define free_initrd_mem.
> >> ...
> >>> --- a/arch/arc/mm/init.c
> >>> +++ b/arch/arc/mm/init.c
> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >>>  {
> >>>  	free_initmem_default(-1);
> >>>  }
> >>> -
> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> >>> -{
> >>> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
> >>> -}
> >>> -#endif
> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >>> index 3f972e83909b..19d1c5594e2d 100644
> >>> --- a/arch/arm/Kconfig
> >>> +++ b/arch/arm/Kconfig
> >>> @@ -47,6 +47,7 @@ config ARM
> >>>  	select HARDIRQS_SW_RESEND
> >>>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >>>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> >>> +	select HAVE_ARCH_FREE_INITRD_MEM
> >>>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >>>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >>>  	select HAVE_ARCH_MMAP_RND_BITS if MMU
> >>
> >> Isn't this why weak symbols were invented?
> > 
> > Weak symbols means that we end up with both the weakly-referenced code
> > and the arch code in the kernel image.  That's fine if the weak code
> > is small.
> 
> The kernel's been able to build with link time garbage collection since 2016:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> 
> Wouldn't that remove the unused one?

Probably, if anyone bothered to use that, which they don't.

LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
what I can see, nothing selects it.  Therefore, the symbol is always
disabled, and so the feature never gets used in mainline kernels.

Brings up the obvious question - why is it there if it's completely
unused?  (Maybe to cause confusion, and allowing a justification
for __weak ?)

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Oliver]

On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
<linux@armlinux.org.uk> wrote:
> On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
>>
>>
>> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
>> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
>> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
>> >>> Now only those architectures that have custom initrd free requirements
>> >>> need to define free_initrd_mem.
>> >> ...
>> >>> --- a/arch/arc/mm/init.c
>> >>> +++ b/arch/arc/mm/init.c
>> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>> >>>  {
>> >>>   free_initmem_default(-1);
>> >>>  }
>> >>> -
>> >>> -#ifdef CONFIG_BLK_DEV_INITRD
>> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
>> >>> -{
>> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
>> >>> -}
>> >>> -#endif
>> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> >>> index 3f972e83909b..19d1c5594e2d 100644
>> >>> --- a/arch/arm/Kconfig
>> >>> +++ b/arch/arm/Kconfig
>> >>> @@ -47,6 +47,7 @@ config ARM
>> >>>   select HARDIRQS_SW_RESEND
>> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
>> >>> + select HAVE_ARCH_FREE_INITRD_MEM
>> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
>> >>
>> >> Isn't this why weak symbols were invented?
>> >
>> > Weak symbols means that we end up with both the weakly-referenced code
>> > and the arch code in the kernel image.  That's fine if the weak code
>> > is small.
>>
>> The kernel's been able to build with link time garbage collection since 2016:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
>>
>> Wouldn't that remove the unused one?
>
> Probably, if anyone bothered to use that, which they don't.
>
> LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> what I can see, nothing selects it.  Therefore, the symbol is always
> disabled, and so the feature never gets used in mainline kernels.
>
> Brings up the obvious question - why is it there if it's completely
> unused?  (Maybe to cause confusion, and allowing a justification
> for __weak ?)

IIRC Nick had some patches to do the arch enablement for powerpc, but
I'm not sure what happened to them though. I suspect it just fell down
Nick's ever growing TODO list.

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Nicholas Piggin]

On Thu, 29 Mar 2018 09:37:52 +1100
Oliver <oohall@gmail.com> wrote:

> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
> <linux@armlinux.org.uk> wrote:
> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:  
> >>
> >>
> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:  
> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:  
> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:  
> >> >>> Now only those architectures that have custom initrd free requirements
> >> >>> need to define free_initrd_mem.  
> >> >> ...  
> >> >>> --- a/arch/arc/mm/init.c
> >> >>> +++ b/arch/arc/mm/init.c
> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >> >>>  {
> >> >>>   free_initmem_default(-1);
> >> >>>  }
> >> >>> -
> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> >> >>> -{
> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
> >> >>> -}
> >> >>> -#endif
> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> >>> index 3f972e83909b..19d1c5594e2d 100644
> >> >>> --- a/arch/arm/Kconfig
> >> >>> +++ b/arch/arm/Kconfig
> >> >>> @@ -47,6 +47,7 @@ config ARM
> >> >>>   select HARDIRQS_SW_RESEND
> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU  
> >> >>
> >> >> Isn't this why weak symbols were invented?  
> >> >
> >> > Weak symbols means that we end up with both the weakly-referenced code
> >> > and the arch code in the kernel image.  That's fine if the weak code
> >> > is small.  
> >>
> >> The kernel's been able to build with link time garbage collection since 2016:
> >>
> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> >>
> >> Wouldn't that remove the unused one?  
> >
> > Probably, if anyone bothered to use that, which they don't.
> >
> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> > what I can see, nothing selects it.  Therefore, the symbol is always
> > disabled, and so the feature never gets used in mainline kernels.
> >
> > Brings up the obvious question - why is it there if it's completely
> > unused?  (Maybe to cause confusion, and allowing a justification
> > for __weak ?)  

Well weak symbols have been used long before it was added.

> IIRC Nick had some patches to do the arch enablement for powerpc, but
> I'm not sure what happened to them though. I suspect it just fell down
> Nick's ever growing TODO list.

Yeah I had started some patches for powerpc and x86 that have ended up
on the back burner. There's been some MIPS people playing with it too.

For the kernel, LD_DEAD_CODE_DATA_ELIMINATION is not great. It can save
a little, but you get issues like any exception table entry or bug table
entry in a function will create a reference back to the function, so the
linker can't trim it away even if nothing else references it.

I'll try to take another look at it within the next few months and
remove it if I can't make progress.

Nicolas Pitre has been doing some much better work on dead code using
real LTO.

Thanks,
Nick

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
> <linux@armlinux.org.uk> wrote:
> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> >>
> >>
> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
> >> >>> Now only those architectures that have custom initrd free requirements
> >> >>> need to define free_initrd_mem.
> >> >> ...
> >> >>> --- a/arch/arc/mm/init.c
> >> >>> +++ b/arch/arc/mm/init.c
> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >> >>>  {
> >> >>>   free_initmem_default(-1);
> >> >>>  }
> >> >>> -
> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> >> >>> -{
> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
> >> >>> -}
> >> >>> -#endif
> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> >>> index 3f972e83909b..19d1c5594e2d 100644
> >> >>> --- a/arch/arm/Kconfig
> >> >>> +++ b/arch/arm/Kconfig
> >> >>> @@ -47,6 +47,7 @@ config ARM
> >> >>>   select HARDIRQS_SW_RESEND
> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
> >> >>
> >> >> Isn't this why weak symbols were invented?
> >> >
> >> > Weak symbols means that we end up with both the weakly-referenced code
> >> > and the arch code in the kernel image.  That's fine if the weak code
> >> > is small.
> >>
> >> The kernel's been able to build with link time garbage collection since 2016:
> >>
> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> >>
> >> Wouldn't that remove the unused one?
> >
> > Probably, if anyone bothered to use that, which they don't.
> >
> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> > what I can see, nothing selects it.  Therefore, the symbol is always
> > disabled, and so the feature never gets used in mainline kernels.
> >
> > Brings up the obvious question - why is it there if it's completely
> > unused?  (Maybe to cause confusion, and allowing a justification
> > for __weak ?)
> 
> IIRC Nick had some patches to do the arch enablement for powerpc, but
> I'm not sure what happened to them though. I suspect it just fell down
> Nick's ever growing TODO list.

I've given it a go on ARM, marking every linker-built table with KEEP()
and comparing the System.map files.  The resulting kernel is around
150k smaller, which seems good.

However, it doesn't boot - and I don't know why.  Booting the kernel
under kvmtool in a VM using virtio-console, I can find no way to get
any kernel messages out of it.  Using lkvm debug, I can see that the
PC is stuck inside die(), and that's the only information I have.
It dies before bringing up the other CPUs, so it's a very early death.

I don't think other console types are available under ARM64.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Geert Uytterhoeven]

On Thu, Mar 29, 2018 at 5:27 PM, Russell King - ARM Linux
<linux@armlinux.org.uk> wrote:
> On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
>> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
>> <linux@armlinux.org.uk> wrote:
>> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
>> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
>> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
>> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
>> >> >>> Now only those architectures that have custom initrd free requirements
>> >> >>> need to define free_initrd_mem.
>> >> >> ...
>> >> >>> --- a/arch/arc/mm/init.c
>> >> >>> +++ b/arch/arc/mm/init.c
>> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>> >> >>>  {
>> >> >>>   free_initmem_default(-1);
>> >> >>>  }
>> >> >>> -
>> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
>> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
>> >> >>> -{
>> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
>> >> >>> -}
>> >> >>> -#endif
>> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> >> >>> index 3f972e83909b..19d1c5594e2d 100644
>> >> >>> --- a/arch/arm/Kconfig
>> >> >>> +++ b/arch/arm/Kconfig
>> >> >>> @@ -47,6 +47,7 @@ config ARM
>> >> >>>   select HARDIRQS_SW_RESEND
>> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
>> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
>> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
>> >> >>
>> >> >> Isn't this why weak symbols were invented?
>> >> >
>> >> > Weak symbols means that we end up with both the weakly-referenced code
>> >> > and the arch code in the kernel image.  That's fine if the weak code
>> >> > is small.
>> >>
>> >> The kernel's been able to build with link time garbage collection since 2016:
>> >>
>> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
>> >>
>> >> Wouldn't that remove the unused one?
>> >
>> > Probably, if anyone bothered to use that, which they don't.
>> >
>> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
>> > what I can see, nothing selects it.  Therefore, the symbol is always
>> > disabled, and so the feature never gets used in mainline kernels.
>> >
>> > Brings up the obvious question - why is it there if it's completely
>> > unused?  (Maybe to cause confusion, and allowing a justification
>> > for __weak ?)
>>
>> IIRC Nick had some patches to do the arch enablement for powerpc, but
>> I'm not sure what happened to them though. I suspect it just fell down
>> Nick's ever growing TODO list.
>
> I've given it a go on ARM, marking every linker-built table with KEEP()
> and comparing the System.map files.  The resulting kernel is around
> 150k smaller, which seems good.
>
> However, it doesn't boot - and I don't know why.  Booting the kernel
> under kvmtool in a VM using virtio-console, I can find no way to get
> any kernel messages out of it.  Using lkvm debug, I can see that the
> PC is stuck inside die(), and that's the only information I have.
> It dies before bringing up the other CPUs, so it's a very early death.
>
> I don't think other console types are available under ARM64.

earlycon?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Thu, Mar 29, 2018 at 05:43:47PM +0200, Geert Uytterhoeven wrote:
> On Thu, Mar 29, 2018 at 5:27 PM, Russell King - ARM Linux
> <linux@armlinux.org.uk> wrote:
> > On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
> >> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
> >> <linux@armlinux.org.uk> wrote:
> >> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> >> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> >> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> >> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
> >> >> >>> Now only those architectures that have custom initrd free requirements
> >> >> >>> need to define free_initrd_mem.
> >> >> >> ...
> >> >> >>> --- a/arch/arc/mm/init.c
> >> >> >>> +++ b/arch/arc/mm/init.c
> >> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >> >> >>>  {
> >> >> >>>   free_initmem_default(-1);
> >> >> >>>  }
> >> >> >>> -
> >> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> >> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> >> >> >>> -{
> >> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
> >> >> >>> -}
> >> >> >>> -#endif
> >> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >> >> >>> index 3f972e83909b..19d1c5594e2d 100644
> >> >> >>> --- a/arch/arm/Kconfig
> >> >> >>> +++ b/arch/arm/Kconfig
> >> >> >>> @@ -47,6 +47,7 @@ config ARM
> >> >> >>>   select HARDIRQS_SW_RESEND
> >> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> >> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
> >> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
> >> >> >>
> >> >> >> Isn't this why weak symbols were invented?
> >> >> >
> >> >> > Weak symbols means that we end up with both the weakly-referenced code
> >> >> > and the arch code in the kernel image.  That's fine if the weak code
> >> >> > is small.
> >> >>
> >> >> The kernel's been able to build with link time garbage collection since 2016:
> >> >>
> >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> >> >>
> >> >> Wouldn't that remove the unused one?
> >> >
> >> > Probably, if anyone bothered to use that, which they don't.
> >> >
> >> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> >> > what I can see, nothing selects it.  Therefore, the symbol is always
> >> > disabled, and so the feature never gets used in mainline kernels.
> >> >
> >> > Brings up the obvious question - why is it there if it's completely
> >> > unused?  (Maybe to cause confusion, and allowing a justification
> >> > for __weak ?)
> >>
> >> IIRC Nick had some patches to do the arch enablement for powerpc, but
> >> I'm not sure what happened to them though. I suspect it just fell down
> >> Nick's ever growing TODO list.
> >
> > I've given it a go on ARM, marking every linker-built table with KEEP()
> > and comparing the System.map files.  The resulting kernel is around
> > 150k smaller, which seems good.
> >
> > However, it doesn't boot - and I don't know why.  Booting the kernel
> > under kvmtool in a VM using virtio-console, I can find no way to get
> > any kernel messages out of it.  Using lkvm debug, I can see that the
> > PC is stuck inside die(), and that's the only information I have.
> > It dies before bringing up the other CPUs, so it's a very early death.
> >
> > I don't think other console types are available under ARM64.
> 
> earlycon?

Through what - as I say above, I think the only thing that's present is
virtio-console, and the virtio stack only get initialised much later in
boot.

Eg, there's the memory-based virtio driver which interfaces any virtio
driver to a memory-based ring structures for communication with the host
(drivers/virtio/virtio_mmio.c) which is initialised at module_init()
time, and so isn't available for earlycon.

I don't think merely changing the module_init() calls in the appropriate
virtio bits will suffice - it's why I pointed out that it dies before
SMP initialisation, which also means that it dies before we start
running the initcalls for subsystems and drivers.

I'm not aware of there being an emulated UART in the guest's address
space, so serial based stuff doesn't work.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Marc Zyngier]

On Thu, 29 Mar 2018 16:58:27 +0100,
Russell King - ARM Linux wrote:
> 
> On Thu, Mar 29, 2018 at 05:43:47PM +0200, Geert Uytterhoeven wrote:
> > On Thu, Mar 29, 2018 at 5:27 PM, Russell King - ARM Linux
> > <linux@armlinux.org.uk> wrote:
> > > On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
> > >> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
> > >> <linux@armlinux.org.uk> wrote:
> > >> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> > >> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> > >> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> > >> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
> > >> >> >>> Now only those architectures that have custom initrd free requirements
> > >> >> >>> need to define free_initrd_mem.
> > >> >> >> ...
> > >> >> >>> --- a/arch/arc/mm/init.c
> > >> >> >>> +++ b/arch/arc/mm/init.c
> > >> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> > >> >> >>>  {
> > >> >> >>>   free_initmem_default(-1);
> > >> >> >>>  }
> > >> >> >>> -
> > >> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> > >> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> > >> >> >>> -{
> > >> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
> > >> >> >>> -}
> > >> >> >>> -#endif
> > >> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > >> >> >>> index 3f972e83909b..19d1c5594e2d 100644
> > >> >> >>> --- a/arch/arm/Kconfig
> > >> >> >>> +++ b/arch/arm/Kconfig
> > >> >> >>> @@ -47,6 +47,7 @@ config ARM
> > >> >> >>>   select HARDIRQS_SW_RESEND
> > >> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> > >> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> > >> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
> > >> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> > >> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> > >> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
> > >> >> >>
> > >> >> >> Isn't this why weak symbols were invented?
> > >> >> >
> > >> >> > Weak symbols means that we end up with both the weakly-referenced code
> > >> >> > and the arch code in the kernel image.  That's fine if the weak code
> > >> >> > is small.
> > >> >>
> > >> >> The kernel's been able to build with link time garbage collection since 2016:
> > >> >>
> > >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> > >> >>
> > >> >> Wouldn't that remove the unused one?
> > >> >
> > >> > Probably, if anyone bothered to use that, which they don't.
> > >> >
> > >> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> > >> > what I can see, nothing selects it.  Therefore, the symbol is always
> > >> > disabled, and so the feature never gets used in mainline kernels.
> > >> >
> > >> > Brings up the obvious question - why is it there if it's completely
> > >> > unused?  (Maybe to cause confusion, and allowing a justification
> > >> > for __weak ?)
> > >>
> > >> IIRC Nick had some patches to do the arch enablement for powerpc, but
> > >> I'm not sure what happened to them though. I suspect it just fell down
> > >> Nick's ever growing TODO list.
> > >
> > > I've given it a go on ARM, marking every linker-built table with KEEP()
> > > and comparing the System.map files.  The resulting kernel is around
> > > 150k smaller, which seems good.
> > >
> > > However, it doesn't boot - and I don't know why.  Booting the kernel
> > > under kvmtool in a VM using virtio-console, I can find no way to get
> > > any kernel messages out of it.  Using lkvm debug, I can see that the
> > > PC is stuck inside die(), and that's the only information I have.
> > > It dies before bringing up the other CPUs, so it's a very early death.
> > >
> > > I don't think other console types are available under ARM64.
> > 
> > earlycon?
> 
> Through what - as I say above, I think the only thing that's present is
> virtio-console, and the virtio stack only get initialised much later in
> boot.
> 
> Eg, there's the memory-based virtio driver which interfaces any virtio
> driver to a memory-based ring structures for communication with the host
> (drivers/virtio/virtio_mmio.c) which is initialised at module_init()
> time, and so isn't available for earlycon.
> 
> I don't think merely changing the module_init() calls in the appropriate
> virtio bits will suffice - it's why I pointed out that it dies before
> SMP initialisation, which also means that it dies before we start
> running the initcalls for subsystems and drivers.
> 
> I'm not aware of there being an emulated UART in the guest's address
> space, so serial based stuff doesn't work.

"earlycon=uart,mmio,0x3f8" is what you're looking for:

$ Work/kvmtool/lkvm run -c2 -k zImage -p "earlycon=uart,mmio,0x3f8" --console virtio --aarch32
  # lkvm run -k zImage -m 320 -c 2 --name guest-3856
  Info: Loaded kernel to 0x80008000 (6767104 bytes)
  Info: Placing fdt at 0x8fe00000 - 0x8fffffff
  Info: virtio-mmio.devices=0x200@0x10000:36

  Info: virtio-mmio.devices=0x200@0x10200:37

  Info: virtio-mmio.devices=0x200@0x10400:38

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Linux version 4.16.0-rc6+ (maz@approximate) (gcc version 6.3.0 20170516 (Debian 6.3.0-18)) #8407 SMP PREEMPT Tue Mar 20 15:01:43 GMT 2018
[    0.000000] CPU: ARMv7 Processor [410fd082] revision 2 (ARMv7), cr=30c5383d
[    0.000000] CPU: div instructions available: patching division code
[    0.000000] CPU: PIPT / VIPT nonaliasing data cache, PIPT instruction cache
[    0.000000] OF: fdt: Machine model: linux,dummy-virt
[    0.000000] earlycon: uart0 at MMIO 0x00000000000003f8 (options '')
[    0.000000] bootconsole [uart0] enabled
[    0.000000] Memory policy: Data cache writealloc
[    0.000000] efi: Getting EFI parameters from FDT:
[    0.000000] efi: UEFI not found.

[...]

	M.

-- 
Jazz is not dead, it just smell funny.

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Thu, Mar 29, 2018 at 05:53:14PM +0100, Marc Zyngier wrote:
> On Thu, 29 Mar 2018 16:58:27 +0100,
> Russell King - ARM Linux wrote:
> > 
> > On Thu, Mar 29, 2018 at 05:43:47PM +0200, Geert Uytterhoeven wrote:
> > > On Thu, Mar 29, 2018 at 5:27 PM, Russell King - ARM Linux
> > > <linux@armlinux.org.uk> wrote:
> > > > On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
> > > >> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
> > > >> <linux@armlinux.org.uk> wrote:
> > > >> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> > > >> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> > > >> >> > On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> > > >> >> >> On 03/28/2018 10:26 AM, Shea Levy wrote:
> > > >> >> >>> Now only those architectures that have custom initrd free requirements
> > > >> >> >>> need to define free_initrd_mem.
> > > >> >> >> ...
> > > >> >> >>> --- a/arch/arc/mm/init.c
> > > >> >> >>> +++ b/arch/arc/mm/init.c
> > > >> >> >>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> > > >> >> >>>  {
> > > >> >> >>>   free_initmem_default(-1);
> > > >> >> >>>  }
> > > >> >> >>> -
> > > >> >> >>> -#ifdef CONFIG_BLK_DEV_INITRD
> > > >> >> >>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> > > >> >> >>> -{
> > > >> >> >>> - free_reserved_area((void *)start, (void *)end, -1, "initrd");
> > > >> >> >>> -}
> > > >> >> >>> -#endif
> > > >> >> >>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > > >> >> >>> index 3f972e83909b..19d1c5594e2d 100644
> > > >> >> >>> --- a/arch/arm/Kconfig
> > > >> >> >>> +++ b/arch/arm/Kconfig
> > > >> >> >>> @@ -47,6 +47,7 @@ config ARM
> > > >> >> >>>   select HARDIRQS_SW_RESEND
> > > >> >> >>>   select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> > > >> >> >>>   select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> > > >> >> >>> + select HAVE_ARCH_FREE_INITRD_MEM
> > > >> >> >>>   select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> > > >> >> >>>   select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> > > >> >> >>>   select HAVE_ARCH_MMAP_RND_BITS if MMU
> > > >> >> >>
> > > >> >> >> Isn't this why weak symbols were invented?
> > > >> >> >
> > > >> >> > Weak symbols means that we end up with both the weakly-referenced code
> > > >> >> > and the arch code in the kernel image.  That's fine if the weak code
> > > >> >> > is small.
> > > >> >>
> > > >> >> The kernel's been able to build with link time garbage collection since 2016:
> > > >> >>
> > > >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> > > >> >>
> > > >> >> Wouldn't that remove the unused one?
> > > >> >
> > > >> > Probably, if anyone bothered to use that, which they don't.
> > > >> >
> > > >> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> > > >> > what I can see, nothing selects it.  Therefore, the symbol is always
> > > >> > disabled, and so the feature never gets used in mainline kernels.
> > > >> >
> > > >> > Brings up the obvious question - why is it there if it's completely
> > > >> > unused?  (Maybe to cause confusion, and allowing a justification
> > > >> > for __weak ?)
> > > >>
> > > >> IIRC Nick had some patches to do the arch enablement for powerpc, but
> > > >> I'm not sure what happened to them though. I suspect it just fell down
> > > >> Nick's ever growing TODO list.
> > > >
> > > > I've given it a go on ARM, marking every linker-built table with KEEP()
> > > > and comparing the System.map files.  The resulting kernel is around
> > > > 150k smaller, which seems good.
> > > >
> > > > However, it doesn't boot - and I don't know why.  Booting the kernel
> > > > under kvmtool in a VM using virtio-console, I can find no way to get
> > > > any kernel messages out of it.  Using lkvm debug, I can see that the
> > > > PC is stuck inside die(), and that's the only information I have.
> > > > It dies before bringing up the other CPUs, so it's a very early death.
> > > >
> > > > I don't think other console types are available under ARM64.
> > > 
> > > earlycon?
> > 
> > Through what - as I say above, I think the only thing that's present is
> > virtio-console, and the virtio stack only get initialised much later in
> > boot.
> > 
> > Eg, there's the memory-based virtio driver which interfaces any virtio
> > driver to a memory-based ring structures for communication with the host
> > (drivers/virtio/virtio_mmio.c) which is initialised at module_init()
> > time, and so isn't available for earlycon.
> > 
> > I don't think merely changing the module_init() calls in the appropriate
> > virtio bits will suffice - it's why I pointed out that it dies before
> > SMP initialisation, which also means that it dies before we start
> > running the initcalls for subsystems and drivers.
> > 
> > I'm not aware of there being an emulated UART in the guest's address
> > space, so serial based stuff doesn't work.
> 
> "earlycon=uart,mmio,0x3f8" is what you're looking for:

Does that also mean that we have a RTC at the standard PC IO addresses
as well, but in mmio space?

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Marc Zyngier]

On Thu, 29 Mar 2018 18:32:47 +0100,
Russell King - ARM Linux wrote:
> 
> On Thu, Mar 29, 2018 at 05:53:14PM +0100, Marc Zyngier wrote:
> > On Thu, 29 Mar 2018 16:58:27 +0100,
> > Russell King - ARM Linux wrote:

[...]

> > > I'm not aware of there being an emulated UART in the guest's address
> > > space, so serial based stuff doesn't work.
> > 
> > "earlycon=uart,mmio,0x3f8" is what you're looking for:
> 
> Does that also mean that we have a RTC at the standard PC IO addresses
> as well, but in mmio space?

There is one, together with an i8042. Not exposed in the DT though.

	M.

-- 
Jazz is not dead, it just smell funny.

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Rob Landley]

[-- Attachment #1: Type: text/plain, Size: 3072 bytes --]

On 03/29/2018 10:27 AM, Russell King - ARM Linux wrote:
> On Thu, Mar 29, 2018 at 09:37:52AM +1100, Oliver wrote:
>> On Thu, Mar 29, 2018 at 9:14 AM, Russell King - ARM Linux
>>> LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
>>> what I can see, nothing selects it.  Therefore, the symbol is always
>>> disabled, and so the feature never gets used in mainline kernels.
>>>
>>> Brings up the obvious question - why is it there if it's completely
>>> unused?  (Maybe to cause confusion, and allowing a justification
>>> for __weak ?)
>>
>> IIRC Nick had some patches to do the arch enablement for powerpc, but
>> I'm not sure what happened to them though. I suspect it just fell down
>> Nick's ever growing TODO list.
> 
> I've given it a go on ARM, marking every linker-built table with KEEP()
> and comparing the System.map files.  The resulting kernel is around
> 150k smaller, which seems good.
> 
> However, it doesn't boot - and I don't know why.  Booting the kernel
> under kvmtool in a VM using virtio-console, I can find no way to get
> any kernel messages out of it.  Using lkvm debug, I can see that the
> PC is stuck inside die(), and that's the only information I have.

qemu-system-arm's "-s" option lets you hook to the hardware with gdb, as if
using one of those jtags that speaks gdbserver protocol. It stops waiting for
you to attach with 'target remote' it, then 'file vmlinux' to load the symbols...

The miniconfig and qemu invocation I use for arm64 are attached, tested with
2.11.0 on a 4.14 kernel. You should be able to just "qemu-aarch64.sh -s" and
then probably "target remote 127.0.0.1:1234"? (Been a while since I've used it,
don't have a cross-gdb for arm64 lying around...)

Sigh, I just tried -s and qemu 2.11.0 is _not_ waiting for gdb to attach on
arm64, despite what the docs say:

$ qemu-system-aarch64 --help | grep gdb
-gdb dev        wait for gdb connection on 'dev'
-s              shorthand for -gdb tcp::1234

Another random regression in qemu, gee what a surprise.

> It dies before bringing up the other CPUs, so it's a very early death.
> 
> I don't think other console types are available under ARM64.

I've often found useful the two line version of:

https://balau82.wordpress.com/2010/02/28/hello-world-for-bare-metal-arm-using-qemu/

Which is generally some variant of:

{char *XX = "blah"; while (*XX) {while (*SERIAL_STATUS_REGISTER & OUT_READY);
*SERIAL_OUT = *XX++;}}

(I.E. balu cheated not spinning checking the ready-for-next-byte bit, because
qemu's always angry.)

That trick lets you cut and paste a print statement into all sorts of early
hardware nonsense, on most architectures. You just have to look up
SERIAL_STATUS_REGISTER, OUT_OK_BIT, and SERIAL_OUT values for the serial port du
jour.

That said I've mostly used it in things like u-boot. I dunno at what point the
kernel's done enough setup that direct banging on registers would stop working.
(Works in the decompresion code, anyway.) And it assumes the port's set to the
right speed (usually left there by the bootloader)...

Rob

[-- Attachment #2: aarch64.miniconf --]
[-- Type: text/plain, Size: 1387 bytes --]

# make ARCH=arm64 allnoconfig KCONFIG_ALLCONFIG=aarch64.miniconf
# make ARCH=arm64 -j $(nproc)
# boot arch/arm64/boot/Image


CONFIG_MMU=y
CONFIG_ARCH_MULTI_V7=y
CONFIG_ARCH_VIRT=y
CONFIG_SOC_DRA7XX=y
CONFIG_ARCH_OMAP2PLUS_TYPICAL=y
CONFIG_ARCH_ALPINE=y
CONFIG_ARM_THUMB=y
CONFIG_VDSO=y
CONFIG_CPU_IDLE=y
CONFIG_ARM_CPUIDLE=y
CONFIG_KERNEL_MODE_NEON=y

CONFIG_SERIAL_AMBA_PL011=y
CONFIG_SERIAL_AMBA_PL011_CONSOLE=y

CONFIG_RTC_CLASS=y
CONFIG_RTC_HCTOSYS=y
CONFIG_RTC_DRV_PL031=y

CONFIG_NET_CORE=y
CONFIG_VIRTIO_NET=y

CONFIG_PCI=y
CONFIG_PCI_HOST_GENERIC=y
CONFIG_VIRTIO_BLK=y
CONFIG_VIRTIO_PCI=y
CONFIG_VIRTIO_MMIO=y

CONFIG_ATA=y
CONFIG_ATA_SFF=y
CONFIG_ATA_BMDMA=y
CONFIG_ATA_PIIX=y

CONFIG_PATA_PLATFORM=y
CONFIG_PATA_OF_PLATFORM=y
CONFIG_ATA_GENERIC=y


# CONFIG_EMBEDDED is not set
CONFIG_EARLY_PRINTK=y
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_SCRIPT=y
CONFIG_NO_HZ=y
CONFIG_HIGH_RES_TIMERS=y

CONFIG_BLK_DEV=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_RD_GZIP=y

CONFIG_BLK_DEV_LOOP=y
CONFIG_EXT4_FS=y
CONFIG_EXT4_USE_FOR_EXT2=y
CONFIG_VFAT_FS=y
CONFIG_FAT_DEFAULT_UTF8=y
CONFIG_MISC_FILESYSTEMS=y
CONFIG_SQUASHFS=y
CONFIG_SQUASHFS_XATTR=y
CONFIG_SQUASHFS_ZLIB=y
CONFIG_DEVTMPFS=y
CONFIG_DEVTMPFS_MOUNT=y
CONFIG_TMPFS=y
CONFIG_TMPFS_POSIX_ACL=y

CONFIG_NET=y
CONFIG_PACKET=y
CONFIG_UNIX=y
CONFIG_INET=y
CONFIG_IPV6=y
CONFIG_NETDEVICES=y
#CONFIG_NET_CORE=y
#CONFIG_NETCONSOLE=y
CONFIG_ETHERNET=y


[-- Attachment #3: qemu-aarch64.sh --]
[-- Type: application/x-shellscript, Size: 186 bytes --]

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Rob Landley]

On 03/28/2018 05:14 PM, Russell King - ARM Linux wrote:
> On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
>>
>>
>> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
>>> On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
>>>> On 03/28/2018 10:26 AM, Shea Levy wrote:
>>>>> Now only those architectures that have custom initrd free requirements
>>>>> need to define free_initrd_mem.
>>>> ...
>>>>> --- a/arch/arc/mm/init.c
>>>>> +++ b/arch/arc/mm/init.c
>>>>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
>>>>>  {
>>>>>  	free_initmem_default(-1);
>>>>>  }
>>>>> -
>>>>> -#ifdef CONFIG_BLK_DEV_INITRD
>>>>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
>>>>> -{
>>>>> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
>>>>> -}
>>>>> -#endif
>>>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>>>>> index 3f972e83909b..19d1c5594e2d 100644
>>>>> --- a/arch/arm/Kconfig
>>>>> +++ b/arch/arm/Kconfig
>>>>> @@ -47,6 +47,7 @@ config ARM
>>>>>  	select HARDIRQS_SW_RESEND
>>>>>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
>>>>>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
>>>>> +	select HAVE_ARCH_FREE_INITRD_MEM
>>>>>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
>>>>>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
>>>>>  	select HAVE_ARCH_MMAP_RND_BITS if MMU
>>>>
>>>> Isn't this why weak symbols were invented?
>>>
>>> Weak symbols means that we end up with both the weakly-referenced code
>>> and the arch code in the kernel image.  That's fine if the weak code
>>> is small.
>>
>> The kernel's been able to build with link time garbage collection since 2016:
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
>>
>> Wouldn't that remove the unused one?
> 
> Probably, if anyone bothered to use that, which they don't.
> 
> LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> what I can see, nothing selects it.  Therefore, the symbol is always
> disabled, and so the feature never gets used in mainline kernels.

It looks like there are per-architecture linker scripts that need to be updated?
So if an architecture supports it, it's always done (well, it probes for the
toolchain supporting the flag). And if the architecture doesn't support it, the
linker script needs to be updated to mark sections with "I know nothing seems to
reference this at the ELF level but keep it anyway, we're pulling an assembly
trick".

> Brings up the obvious question - why is it there if it's completely
> unused?  (Maybe to cause confusion, and allowing a justification
> for __weak ?)

Presumably it will become the default on architectures as their linker scripts
are converted. Once they're all converted the config symbol can go away. (Given
the move to requiring gcc 4.7 or whatever it is, there can't be an architecture
depending on a toolchain that _doesn't_ support it after that point. I doubt you
can pair gcc 4.7 with a >12 year old binutils and expect good things...)

Rob

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Russell King - ARM Linux]

On Thu, Mar 29, 2018 at 11:39:24AM -0500, Rob Landley wrote:
> 
> 
> On 03/28/2018 05:14 PM, Russell King - ARM Linux wrote:
> > On Wed, Mar 28, 2018 at 02:04:22PM -0500, Rob Landley wrote:
> >>
> >>
> >> On 03/28/2018 11:48 AM, Russell King - ARM Linux wrote:
> >>> On Wed, Mar 28, 2018 at 10:58:51AM -0500, Rob Landley wrote:
> >>>> On 03/28/2018 10:26 AM, Shea Levy wrote:
> >>>>> Now only those architectures that have custom initrd free requirements
> >>>>> need to define free_initrd_mem.
> >>>> ...
> >>>>> --- a/arch/arc/mm/init.c
> >>>>> +++ b/arch/arc/mm/init.c
> >>>>> @@ -229,10 +229,3 @@ void __ref free_initmem(void)
> >>>>>  {
> >>>>>  	free_initmem_default(-1);
> >>>>>  }
> >>>>> -
> >>>>> -#ifdef CONFIG_BLK_DEV_INITRD
> >>>>> -void __init free_initrd_mem(unsigned long start, unsigned long end)
> >>>>> -{
> >>>>> -	free_reserved_area((void *)start, (void *)end, -1, "initrd");
> >>>>> -}
> >>>>> -#endif
> >>>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> >>>>> index 3f972e83909b..19d1c5594e2d 100644
> >>>>> --- a/arch/arm/Kconfig
> >>>>> +++ b/arch/arm/Kconfig
> >>>>> @@ -47,6 +47,7 @@ config ARM
> >>>>>  	select HARDIRQS_SW_RESEND
> >>>>>  	select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
> >>>>>  	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
> >>>>> +	select HAVE_ARCH_FREE_INITRD_MEM
> >>>>>  	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
> >>>>>  	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
> >>>>>  	select HAVE_ARCH_MMAP_RND_BITS if MMU
> >>>>
> >>>> Isn't this why weak symbols were invented?
> >>>
> >>> Weak symbols means that we end up with both the weakly-referenced code
> >>> and the arch code in the kernel image.  That's fine if the weak code
> >>> is small.
> >>
> >> The kernel's been able to build with link time garbage collection since 2016:
> >>
> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b67067f1176d
> >>
> >> Wouldn't that remove the unused one?
> > 
> > Probably, if anyone bothered to use that, which they don't.
> > 
> > LD_DEAD_CODE_DATA_ELIMINATION is a symbol without a prompt, and from
> > what I can see, nothing selects it.  Therefore, the symbol is always
> > disabled, and so the feature never gets used in mainline kernels.
> 
> It looks like there are per-architecture linker scripts that need to be updated?
> So if an architecture supports it, it's always done (well, it probes for the
> toolchain supporting the flag). And if the architecture doesn't support it, the
> linker script needs to be updated to mark sections with "I know nothing seems to
> reference this at the ELF level but keep it anyway, we're pulling an assembly
> trick".

It looks like it needs much more than just architecture changes as the
reason it fails on ARM is because the init thread structure is missing
due to missing KEEP()s in INIT_TASK_DATA().  Probably means it doesn't
work anywhere.

8<===
From: Russell King <rmk+kernel@armlinux.org.uk>
Subject: [PATCH] Fix LD_DEAD_CODE_DATA_ELIMINATION

LD_DEAD_CODE_DATA_ELIMINATION fails to boot on ARM because the linker
eliminates the init thread data from the bottom of the init threads
stack.  This causes recursive faults that end up overwriting parts
of the kernel before they can print any message.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 include/asm-generic/vmlinux.lds.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 1ab0e520d6fc..41af8a74aae4 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -279,8 +279,8 @@
 	VMLINUX_SYMBOL(__start_init_task) = .;				\
 	VMLINUX_SYMBOL(init_thread_union) = .;				\
 	VMLINUX_SYMBOL(init_stack) = .;					\
-	*(.data..init_task)						\
-	*(.data..init_thread_info)					\
+	KEEP(*(.data..init_task))					\
+	KEEP(*(.data..init_thread_info))				\
 	. = VMLINUX_SYMBOL(__start_init_task) + THREAD_SIZE;		\
 	VMLINUX_SYMBOL(__end_init_task) = .;
 

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Kees Cook]

On Wed, Mar 28, 2018 at 8:26 AM, Shea Levy <shea@shealevy.com> wrote:
> Now only those architectures that have custom initrd free requirements
> need to define free_initrd_mem.
>
> Signed-off-by: Shea Levy <shea@shealevy.com>

Yay consolidation! :)

> --- a/usr/Kconfig
> +++ b/usr/Kconfig
> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>         default ".lzma" if RD_LZMA
>         default ".bz2"  if RD_BZIP2
>         default ""
> +
> +config HAVE_ARCH_FREE_INITRD_MEM
> +       bool
> +       default n

If you keep the Kconfig, you can leave off "default n", and I'd
suggest adding a help section just to describe what the per-arch
responsibilities are when select-ing the config. (See
HAVE_ARCH_SECCOMP_FILTER for an example.)

-Kees

-- 
Kees Cook
Pixel Security

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Wei Yang]

On Wed, Mar 28, 2018 at 09:55:07AM -0700, Kees Cook wrote:
>On Wed, Mar 28, 2018 at 8:26 AM, Shea Levy <shea@shealevy.com> wrote:
>> Now only those architectures that have custom initrd free requirements
>> need to define free_initrd_mem.
>>
>> Signed-off-by: Shea Levy <shea@shealevy.com>
>
>Yay consolidation! :)
>
>> --- a/usr/Kconfig
>> +++ b/usr/Kconfig
>> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>>         default ".lzma" if RD_LZMA
>>         default ".bz2"  if RD_BZIP2
>>         default ""
>> +
>> +config HAVE_ARCH_FREE_INITRD_MEM
>> +       bool
>> +       default n
>
>If you keep the Kconfig, you can leave off "default n", and I'd
>suggest adding a help section just to describe what the per-arch
>responsibilities are when select-ing the config. (See
>HAVE_ARCH_SECCOMP_FILTER for an example.)
>

One question about this change.

The original code would "select" HAVE_ARCH_FREE_INITRD_MEM on those arch.
After this change, we need to manually "select" this?

>-Kees
>
>-- 
>Kees Cook
>Pixel Security

-- 
Wei Yang
Help you, Help me

[PATCH v4 14/16] powerpc: Use generic free_initrd_mem.

[Shea Levy]

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/powerpc/mm/mem.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
-- 
2.16.2

Re: [PATCH v4 14/16] powerpc: Use generic free_initrd_mem.

[Joe Perches]

On Wed, 2018-03-28 at 16:36 -0400, Shea Levy wrote:
> Signed-off-by: Shea Levy <shea@shealevy.com>

Most people seem to want some form of commit message
and not just your sign-off.

And btw:

It seems you used get_maintainer to determine who to
send these patches to.

I suggest you add --nogit and --nogit-fallback to the
get_maintainer command line you use to avoid sending
these patches to people like me that have done drive-by
cleanup work on these files.

Re: [PATCH v4 14/16] powerpc: Use generic free_initrd_mem.

[Shea Levy]

[-- Attachment #1: Type: text/plain, Size: 645 bytes --]

Joe Perches <joe@perches.com> writes:

> On Wed, 2018-03-28 at 16:36 -0400, Shea Levy wrote:
>> Signed-off-by: Shea Levy <shea@shealevy.com>
>
> Most people seem to want some form of commit message
> and not just your sign-off.
>

Ah, if the subject is insufficient I can add some more detail.

>
> And btw:
>
> It seems you used get_maintainer to determine who to
> send these patches to.
>
> I suggest you add --nogit and --nogit-fallback to the
> get_maintainer command line you use to avoid sending
> these patches to people like me that have done drive-by
> cleanup work on these files.

Whoops, thanks for the tip and sorry for the noise!

[-- Attachment #2: signature.asc --]
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Re: [PATCH v4 14/16] powerpc: Use generic free_initrd_mem.

[Michael Ellerman]

Shea Levy <shea@shealevy.com> writes:

> Joe Perches <joe@perches.com> writes:
>
>> On Wed, 2018-03-28 at 16:36 -0400, Shea Levy wrote:
>>> Signed-off-by: Shea Levy <shea@shealevy.com>
>>
>> Most people seem to want some form of commit message
>> and not just your sign-off.
>>
>
> Ah, if the subject is insufficient I can add some more detail.

Yeah please do.

Seeing this patch in isolation, with no change log, I might think it's
safe for me to just apply it.

But that would break the build because I don't have patch 1.

So for starters you need to explain that part, eg something like:

  A previous patch in the series added a weak definition of
  free_initrd_mem() in init/initramfs.c.

  The powerpc implementation is identical, so it can be removed allowing
  the generic version to be used.


Then you could also tell me if you did/didn't build/boot test it.

cheers

Re: [PATCH v4 14/16] powerpc: Use generic free_initrd_mem.

[Shea Levy]

[-- Attachment #1: Type: text/plain, Size: 1085 bytes --]

Hi Michael,

Michael Ellerman <mpe@ellerman.id.au> writes:

> Shea Levy <shea@shealevy.com> writes:
>
>> Joe Perches <joe@perches.com> writes:
>>
>>> On Wed, 2018-03-28 at 16:36 -0400, Shea Levy wrote:
>>>> Signed-off-by: Shea Levy <shea@shealevy.com>
>>>
>>> Most people seem to want some form of commit message
>>> and not just your sign-off.
>>>
>>
>> Ah, if the subject is insufficient I can add some more detail.
>
> Yeah please do.
>
> Seeing this patch in isolation, with no change log, I might think it's
> safe for me to just apply it.
>
> But that would break the build because I don't have patch 1.
>
> So for starters you need to explain that part, eg something like:
>
>   A previous patch in the series added a weak definition of
>   free_initrd_mem() in init/initramfs.c.
>
>   The powerpc implementation is identical, so it can be removed allowing
>   the generic version to be used.
>
>
> Then you could also tell me if you did/didn't build/boot test it.

Thanks for the feedback, can you let me know if the recently posted v6
fits the bill?

>
> cheers

Thanks,
Shea

[-- Attachment #2: signature.asc --]
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[PATCH v5 14/16] powerpc: Switch to generic free_initrd_mem.

[Shea Levy]

The generic implementation is functionally identical.

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/powerpc/mm/mem.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
-- 
2.16.2

[PATCH v6 14/16] powerpc: Switch to generic free_initrd_mem.

[Shea Levy]

The first patch in this series added a weakly-defined generic
implementation, which is functionally identical to the
architecture-specific one removed here.

Series boot-tested on RISC-V (which now uses the generic
implementation) and x86_64 (which doesn't).

Signed-off-by: Shea Levy <shea@shealevy.com>
---
 arch/powerpc/mm/mem.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index fe8c61149fb8..e85b2a3cd264 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -404,13 +404,6 @@ void free_initmem(void)
 	free_initmem_default(POISON_FREE_INITMEM);
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void __init free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /*
  * This is called when a page has been modified by the kernel.
  * It just marks the page as not i-cache clean.  We do the i-cache
-- 
2.16.2

Re: [PATCH] Extract initrd free logic from arch-specific code.

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1031 bytes --]

Hi Shea,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.16-rc7]
[cannot apply to next-20180329]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Shea-Levy/Extract-initrd-free-logic-from-arch-specific-code/20180330-085507
config: ia64-allnoconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=ia64 

All warnings (new ones prefixed by >>):

warning: (IA64) selects HAVE_ARCH_FREE_INITRD_MEM which has unmet direct dependencies (BLK_DEV_INITRD)

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 5949 bytes --]

Re: [PATCH] Extract initrd free logic from arch-specific code.

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 1038 bytes --]

Hi Shea,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.16-rc7]
[cannot apply to next-20180329]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Shea-Levy/Extract-initrd-free-logic-from-arch-specific-code/20180330-085507
config: m32r-m32104ut_defconfig (attached as .config)
compiler: m32r-linux-gcc (GCC) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=m32r 

All warnings (new ones prefixed by >>):

warning: (M32R) selects HAVE_ARCH_FREE_INITRD_MEM which has unmet direct dependencies (BLK_DEV_INITRD)

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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Re: [PATCH] Extract initrd free logic from arch-specific code.

[Ingo Molnar]

* Shea Levy <shea@shealevy.com> wrote:

> Now only those architectures that have custom initrd free requirements
> need to define free_initrd_mem.
> 
> Signed-off-by: Shea Levy <shea@shealevy.com>

Please put the Kconfig symbol name this patch introduces both into the title, so 
that people know what to grep for.

> ---
>  arch/alpha/mm/init.c      |  8 --------
>  arch/arc/mm/init.c        |  7 -------
>  arch/arm/Kconfig          |  1 +
>  arch/arm64/Kconfig        |  1 +
>  arch/blackfin/Kconfig     |  1 +
>  arch/c6x/mm/init.c        |  7 -------
>  arch/cris/Kconfig         |  1 +
>  arch/frv/mm/init.c        | 11 -----------
>  arch/h8300/mm/init.c      |  7 -------
>  arch/hexagon/Kconfig      |  1 +
>  arch/ia64/Kconfig         |  1 +
>  arch/m32r/Kconfig         |  1 +
>  arch/m32r/mm/init.c       | 11 -----------
>  arch/m68k/mm/init.c       |  7 -------
>  arch/metag/Kconfig        |  1 +
>  arch/microblaze/mm/init.c |  7 -------
>  arch/mips/Kconfig         |  1 +
>  arch/mn10300/Kconfig      |  1 +
>  arch/nios2/mm/init.c      |  7 -------
>  arch/openrisc/mm/init.c   |  7 -------
>  arch/parisc/mm/init.c     |  7 -------
>  arch/powerpc/mm/mem.c     |  7 -------
>  arch/riscv/mm/init.c      |  6 ------
>  arch/s390/Kconfig         |  1 +
>  arch/score/Kconfig        |  1 +
>  arch/sh/mm/init.c         |  7 -------
>  arch/sparc/Kconfig        |  1 +
>  arch/tile/Kconfig         |  1 +
>  arch/um/kernel/mem.c      |  7 -------
>  arch/unicore32/Kconfig    |  1 +
>  arch/x86/Kconfig          |  1 +
>  arch/xtensa/Kconfig       |  1 +
>  init/initramfs.c          |  7 +++++++
>  usr/Kconfig               |  4 ++++
>  34 files changed, 28 insertions(+), 113 deletions(-)

Please also put it into Documentation/features/.

> diff --git a/usr/Kconfig b/usr/Kconfig
> index 43658b8a975e..7a94f6df39bf 100644
> --- a/usr/Kconfig
> +++ b/usr/Kconfig
> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>  	default ".lzma" if RD_LZMA
>  	default ".bz2"  if RD_BZIP2
>  	default ""
> +
> +config HAVE_ARCH_FREE_INITRD_MEM
> +	bool
> +	default n

Help text would be nice, to tell arch maintainers what the purpose of this switch 
is.

Also, a nit, I think this should be named "ARCH_HAS_FREE_INITRD_MEM", which is the 
dominant pattern:

triton:~/tip> git grep 'select.*ARCH' arch/x86/Kconfig* | cut -f2 | cut -d_ -f1-2 | sort | uniq -c | sort -n
    ...
      2 select ARCH_USES
      2 select ARCH_WANTS
      3 select ARCH_MIGHT
      3 select ARCH_WANT
      4 select ARCH_SUPPORTS
      4 select ARCH_USE
     16 select HAVE_ARCH
     23 select ARCH_HAS

It also reads nicely in English:

  "arch has free_initrd_mem()"

While the other makes little sense:

  "have arch free_initrd_mem()"

?

Thanks,

	Ingo

Re: [PATCH] Extract initrd free logic from arch-specific code.

[Shea Levy]

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Hi Ingo,

Ingo Molnar <mingo@kernel.org> writes:

> * Shea Levy <shea@shealevy.com> wrote:
>
>> Now only those architectures that have custom initrd free requirements
>> need to define free_initrd_mem.
>> 
>> Signed-off-by: Shea Levy <shea@shealevy.com>
>
> Please put the Kconfig symbol name this patch introduces both into the title, so 
> that people know what to grep for.
>
>> ---
>>  arch/alpha/mm/init.c      |  8 --------
>>  arch/arc/mm/init.c        |  7 -------
>>  arch/arm/Kconfig          |  1 +
>>  arch/arm64/Kconfig        |  1 +
>>  arch/blackfin/Kconfig     |  1 +
>>  arch/c6x/mm/init.c        |  7 -------
>>  arch/cris/Kconfig         |  1 +
>>  arch/frv/mm/init.c        | 11 -----------
>>  arch/h8300/mm/init.c      |  7 -------
>>  arch/hexagon/Kconfig      |  1 +
>>  arch/ia64/Kconfig         |  1 +
>>  arch/m32r/Kconfig         |  1 +
>>  arch/m32r/mm/init.c       | 11 -----------
>>  arch/m68k/mm/init.c       |  7 -------
>>  arch/metag/Kconfig        |  1 +
>>  arch/microblaze/mm/init.c |  7 -------
>>  arch/mips/Kconfig         |  1 +
>>  arch/mn10300/Kconfig      |  1 +
>>  arch/nios2/mm/init.c      |  7 -------
>>  arch/openrisc/mm/init.c   |  7 -------
>>  arch/parisc/mm/init.c     |  7 -------
>>  arch/powerpc/mm/mem.c     |  7 -------
>>  arch/riscv/mm/init.c      |  6 ------
>>  arch/s390/Kconfig         |  1 +
>>  arch/score/Kconfig        |  1 +
>>  arch/sh/mm/init.c         |  7 -------
>>  arch/sparc/Kconfig        |  1 +
>>  arch/tile/Kconfig         |  1 +
>>  arch/um/kernel/mem.c      |  7 -------
>>  arch/unicore32/Kconfig    |  1 +
>>  arch/x86/Kconfig          |  1 +
>>  arch/xtensa/Kconfig       |  1 +
>>  init/initramfs.c          |  7 +++++++
>>  usr/Kconfig               |  4 ++++
>>  34 files changed, 28 insertions(+), 113 deletions(-)
>
> Please also put it into Documentation/features/.
>

I switched this patch series (the latest revision v6 was just posted) to
using weak symbols instead of Kconfig. Does it still warrant documentation?

>
>> diff --git a/usr/Kconfig b/usr/Kconfig
>> index 43658b8a975e..7a94f6df39bf 100644
>> --- a/usr/Kconfig
>> +++ b/usr/Kconfig
>> @@ -233,3 +233,7 @@ config INITRAMFS_COMPRESSION
>>  	default ".lzma" if RD_LZMA
>>  	default ".bz2"  if RD_BZIP2
>>  	default ""
>> +
>> +config HAVE_ARCH_FREE_INITRD_MEM
>> +	bool
>> +	default n
>
> Help text would be nice, to tell arch maintainers what the purpose of this switch 
> is.
>
> Also, a nit, I think this should be named "ARCH_HAS_FREE_INITRD_MEM", which is the 
> dominant pattern:
>
> triton:~/tip> git grep 'select.*ARCH' arch/x86/Kconfig* | cut -f2 | cut -d_ -f1-2 | sort | uniq -c | sort -n
>     ...
>       2 select ARCH_USES
>       2 select ARCH_WANTS
>       3 select ARCH_MIGHT
>       3 select ARCH_WANT
>       4 select ARCH_SUPPORTS
>       4 select ARCH_USE
>      16 select HAVE_ARCH
>      23 select ARCH_HAS
>
> It also reads nicely in English:
>
>   "arch has free_initrd_mem()"
>
> While the other makes little sense:
>
>   "have arch free_initrd_mem()"
>
> ?
>
> Thanks,
>
> 	Ingo

Thanks,
Shea

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Re: [PATCH] Extract initrd free logic from arch-specific code.

[Ingo Molnar]

* Shea Levy <shea@shealevy.com> wrote:

> > Please also put it into Documentation/features/.
> 
> I switched this patch series (the latest revision v6 was just posted) to
> using weak symbols instead of Kconfig. Does it still warrant documentation?

Probably not.

Thanks,

	Ingo