Message-ID: <3f095b5d-ced2-1c8a-9bd2-2ff2a9480fa1@axentia.se>
Date: Tue, 23 Apr 2024 11:52:52 +0200
From: Peter Rosin <peda@...ntia.se>
To: Arnd Bergmann <arnd@...nel.org>, linux-kernel@...r.kernel.org,
 Corey Minyard <minyard@....org>, Peter Huewe <peterhuewe@....de>,
 Jarkko Sakkinen <jarkko@...nel.org>, Vinod Koul <vkoul@...nel.org>,
 Moritz Fischer <mdf@...nel.org>, Wu Hao <hao.wu@...el.com>,
 Xu Yilun <yilun.xu@...el.com>, Jiri Kosina <jikos@...nel.org>,
 Benjamin Tissoires <benjamin.tissoires@...hat.com>,
 Michael Hennerich <michael.hennerich@...log.com>,
 Dmitry Torokhov <dmitry.torokhov@...il.com>,
 Iyappan Subramanian <iyappan@...amperecomputing.com>,
 Keyur Chudgar <keyur@...amperecomputing.com>,
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>,
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
 Yisen Zhuang <yisen.zhuang@...wei.com>, Salil Mehta
 <salil.mehta@...wei.com>, Tony Lindgren <tony@...mide.com>,
 Liam Girdwood <lgirdwood@...il.com>, Mark Brown <broonie@...nel.org>,
 Alexandre Belloni <alexandre.belloni@...tlin.com>,
 Xiang Chen <chenxiang66@...ilicon.com>,
 "James E.J. Bottomley" <jejb@...ux.ibm.com>,
 "Martin K. Petersen" <martin.petersen@...cle.com>,
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
 Russell King <linux@...linux.org.uk>, Jiri Slaby <jirislaby@...nel.org>,
 Jacky Huang <ychuang3@...oton.com>, Shan-Chun Hung <schung@...oton.com>
Cc: Arnd Bergmann <arnd@...db.de>, Jason Gunthorpe <jgg@...pe.ca>,
 Tom Rix <trix@...hat.com>, Uwe Kleine-König
 <u.kleine-koenig@...gutronix.de>, Randy Dunlap <rdunlap@...radead.org>,
 Rob Herring <robh@...nel.org>, Linus Walleij <linus.walleij@...aro.org>,
 openipmi-developer@...ts.sourceforge.net, linux-integrity@...r.kernel.org,
 dmaengine@...r.kernel.org, linux-fpga@...r.kernel.org,
 linux-input@...r.kernel.org, linux-i2c@...r.kernel.org,
 netdev@...r.kernel.org, linux-omap@...r.kernel.org,
 linux-rtc@...r.kernel.org, linux-scsi@...r.kernel.org,
 linux-staging@...ts.linux.dev, linux-serial@...r.kernel.org,
 linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 33/34] drivers: remove incorrect of_match_ptr/ACPI_PTR
 annotations

Hi!

2024-04-03 at 10:06, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@...db.de>
> 
> When building with CONFIG_OF and/or CONFIG_ACPI disabled but W=1 extra
> warnings enabled, a lot of driver cause a warning about an unused
> ID table:
> 
> drivers/char/tpm/tpm_ftpm_tee.c:356:34: error: unused variable 'of_ftpm_tee_ids' [-Werror,-Wunused-const-variable]
> drivers/dma/img-mdc-dma.c:863:34: error: unused variable 'mdc_dma_of_match' [-Werror,-Wunused-const-variable]
> drivers/fpga/versal-fpga.c:62:34: error: unused variable 'versal_fpga_of_match' [-Werror,-Wunused-const-variable]
> drivers/i2c/muxes/i2c-mux-ltc4306.c:200:34: error: unused variable 'ltc4306_of_match' [-Werror,-Wunused-const-variable]
> drivers/i2c/muxes/i2c-mux-reg.c:242:34: error: unused variable 'i2c_mux_reg_of_match' [-Werror,-Wunused-const-variable]
> drivers/memory/pl353-smc.c:62:34: error: unused variable 'pl353_smc_supported_children' [-Werror,-Wunused-const-variable]
> drivers/regulator/pbias-regulator.c:136:34: error: unused variable 'pbias_of_match' [-Werror,-Wunused-const-variable]
> drivers/regulator/twl-regulator.c:552:34: error: unused variable 'twl_of_match' [-Werror,-Wunused-const-variable]
> drivers/regulator/twl6030-regulator.c:645:34: error: unused variable 'twl_of_match' [-Werror,-Wunused-const-variable]
> drivers/scsi/hisi_sas/hisi_sas_v2_hw.c:3635:36: error: unused variable 'sas_v2_acpi_match' [-Werror,-Wunused-const-variable]
> drivers/staging/pi433/pi433_if.c:1359:34: error: unused variable 'pi433_dt_ids' [-Werror,-Wunused-const-variable]
> drivers/tty/serial/amba-pl011.c:2945:34: error: unused variable 'sbsa_uart_of_match' [-Werror,-Wunused-const-variable]
> 
> The fix is always to just remove the of_match_ptr() and ACPI_PTR() wrappers
> that remove the reference, rather than adding another #ifdef just for build
> testing for a configuration that doesn't matter in practice.
> 
> I considered splitting up the large patch into per subsystem patches, but since
> it's really just the same thing everywhere it feels better to do it all at once.
> 
> Signed-off-by: Arnd Bergmann <arnd@...db.de>
> ---
>  drivers/char/ipmi/ipmb_dev_int.c          | 2 +-
>  drivers/char/tpm/tpm_ftpm_tee.c           | 2 +-
>  drivers/dma/img-mdc-dma.c                 | 2 +-
>  drivers/fpga/versal-fpga.c                | 2 +-
>  drivers/hid/hid-google-hammer.c           | 6 ++----
>  drivers/i2c/muxes/i2c-mux-ltc4306.c       | 2 +-
>  drivers/i2c/muxes/i2c-mux-reg.c           | 2 +-
>  drivers/input/touchscreen/wdt87xx_i2c.c   | 2 +-
>  drivers/mux/adg792a.c                     | 2 +-
>  drivers/net/ethernet/apm/xgene-v2/main.c  | 2 +-
>  drivers/net/ethernet/hisilicon/hns_mdio.c | 2 +-
>  drivers/regulator/pbias-regulator.c       | 2 +-
>  drivers/regulator/twl-regulator.c         | 2 +-
>  drivers/regulator/twl6030-regulator.c     | 2 +-
>  drivers/rtc/rtc-fsl-ftm-alarm.c           | 2 +-
>  drivers/scsi/hisi_sas/hisi_sas_v1_hw.c    | 2 +-
>  drivers/scsi/hisi_sas/hisi_sas_v2_hw.c    | 2 +-
>  drivers/staging/pi433/pi433_if.c          | 2 +-
>  drivers/tty/serial/amba-pl011.c           | 6 +++---
>  drivers/tty/serial/ma35d1_serial.c        | 2 +-
>  20 files changed, 23 insertions(+), 25 deletions(-)

As far as I can tell, this triggers unconditional use of the
.of_match_table, and the compiler will have a harder time dropping
that data. However, the wasted data is negligible for the parts
touching "my" drivers:

drivers/i2c/muxes/i2c-mux-ltc4306.c
drivers/i2c/muxes/i2c-mux-reg.c
drivers/mux/adg729a.c

Acked-by: Peter Rosin <peda@...ntia.se>

Cheers,
Peter

Powered by blists - more mailing lists