From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Dietrich Subject: Re: [PATCH] ARM: tegra: paz00: fix __initdata placement Date: Tue, 24 Jan 2017 10:08:16 +0100 Message-ID: <3638459.E7Mh7VRDt6@fb07-iapwap2> References: <20170123074347.GA29804@dtor-ws> <4072003.S1IBmddlP7@fb07-iapwap2> <20170123162428.GB2043@ulmo.ba.sec> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1811720.MHOpLJvz2D"; micalg="pgp-sha256"; protocol="application/pgp-signature" Return-path: In-Reply-To: <20170123162428.GB2043@ulmo.ba.sec> Sender: linux-kernel-owner@vger.kernel.org To: Thierry Reding Cc: Dmitry Torokhov , Stephen Warren , Alexandre Courbot , Heikki Krogerus , linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org --nextPart1811720.MHOpLJvz2D Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="ISO-8859-1" Hello Thierry, Am Montag, 23. Januar 2017, 17:24:28 CET schrieb Thierry Reding: > On Mon, Jan 23, 2017 at 11:04:22AM +0100, Marc Dietrich wrote: > > Hello Dmitry, > > > > Am Sonntag, 22. Januar 2017, 23:43:47 CET schrieb Dmitry Torokhov: > > > To have expected effect the __initdata attribute should go after > > > variable > > > name and before initializer.` > > > > > > Signed-off-by: Dmitry Torokhov > > > --- > > > > > > arch/arm/mach-tegra/board-paz00.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/arch/arm/mach-tegra/board-paz00.c > > > b/arch/arm/mach-tegra/board-paz00.c index 7478f6fb3664..ea6bff404161 > > > 100644 > > > --- a/arch/arm/mach-tegra/board-paz00.c > > > +++ b/arch/arm/mach-tegra/board-paz00.c > > > @@ -23,7 +23,7 @@ > > > > > > #include "board.h" > > > > > > -static struct property_entry __initdata wifi_rfkill_prop[] = { > > > +static struct property_entry wifi_rfkill_prop[] __initdata = { > > > > > > PROPERTY_ENTRY_STRING("name", "wifi_rfkill"), > > > PROPERTY_ENTRY_STRING("type", "wlan"), > > > { }, > > > > you are right according to the documentation, but objdump -s always shows > > that it gets put into the .rodata section. So this patch has no effect, > > because result is always same (and wrong). It's also possible that I'm > > doing something wrong :-) Btw, there are hundreds of such __initdata > > misplacement in the kernel. > > Hmm... I get this: > > $ objdump -t build/tegra20/arch/arm/mach-tegra/board-paz00.o > > build/tegra20/arch/arm/mach-tegra/board-paz00.o: file format > elf32-little > > SYMBOL TABLE: > 00000000 l df *ABS* 00000000 board-paz00.c > 00000000 l d .text 00000000 .text > 00000000 l d .data 00000000 .data > 00000000 l d .bss 00000000 .bss > 00000000 l d .init.text 00000000 .init.text > 00000000 l .init.text 00000000 $a > 00000000 l .data 00000000 .LANCHOR1 > 00000000 l .init.data 00000000 .LANCHOR0 > 00000000 l d .ARM.extab.init.text 00000000 .ARM.extab.init.text > 00000000 l d .ARM.exidx.init.text 00000000 .ARM.exidx.init.text > 00000000 l .ARM.exidx.init.text 00000000 $d > 00000000 l .data 00000000 $d > 00000000 l O .data 000001c8 wifi_rfkill_device > 000001c8 l O .data 00000048 wifi_gpio_lookup > 00000000 l d .rodata.str1.4 00000000 .rodata.str1.4 > 00000000 l .rodata.str1.4 00000000 $d > 00000000 l d .init.data 00000000 .init.data > 00000000 l .init.data 00000000 $d > 00000000 l O .init.data 00000048 wifi_rfkill_prop > 00000000 l d .debug_frame 00000000 .debug_frame > 00000010 l .debug_frame 00000000 $d > 00000000 l d .debug_info 00000000 .debug_info > 00000000 l d .debug_abbrev 00000000 .debug_abbrev > 00000000 l d .debug_aranges 00000000 .debug_aranges > 00000000 l d .debug_ranges 00000000 .debug_ranges > 00000000 l d .debug_line 00000000 .debug_line > 00000000 l d .debug_str 00000000 .debug_str > 00000000 l d .note.GNU-stack 00000000 .note.GNU-stack > 00000000 l d .comment 00000000 .comment > 00000000 l d .ARM.attributes 00000000 .ARM.attributes > 00000000 g F .init.text 00000030 tegra_paz00_wifikill_init > 00000000 *UND* 00000000 platform_device_add_properties > 00000000 *UND* 00000000 gpiod_add_lookup_table > 00000000 *UND* 00000000 platform_device_register > 00000000 *UND* 00000000 __aeabi_unwind_cpp_pr0 > > So it correctly ends up in .init.data for me. And it does so with or > without the patch. GCCs documentation doesn't seem to say where exactly > these attributes need to be put, though the examples given all have the > attribute right before the =. ok, objdump -s is maybe not appropriate to display such things. Contents of section .init.data: 0000 2c000000 0c000000 00010000 00000000 ,............... 0010 34000000 00000000 40000000 05000000 4.......@....... 0020 00010000 00000000 48000000 00000000 ........H....... 0030 00000000 00000000 00000000 00000000 ................ 0040 00000000 00000000 ........ Contents of section .rodata.str1.4: 0000 72666b69 6c6c5f67 70696f00 74656772 rfkill_gpio.tegr 0010 612d6770 696f0000 72657365 74000000 a-gpio..reset... 0020 73687574 646f776e 00000000 6e616d65 shutdown....name 0030 00000000 77696669 5f72666b 696c6c00 ....wifi_rfkill. 0040 74797065 00000000 776c616e 00 type....wlan. In fact, .init.data seems to contain relocations to .rodata.str1.4, which "-s" does not resolve. > Oh... interestingly checkpatch does seem to have a check for this now, > and it does recommend that __initdata be placed after wifi_rfkill_prop, > so I'm going to apply this. Btw, where is your tree for 4.11? git.kernel.org shows no action since November. Please also include https://patchwork.ozlabs.org/patch/704367/ if you haven't done yet. I forgot to add a #stable tag for 4.9 and 4.10. Marc --nextPart1811720.MHOpLJvz2D Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. 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