Re: [PATCH 00/27 5.10.y] Backport minmax.h updates from v6.17-rc6

Christian König
2025-09-22T08:46:16Z

On 20.09.25 12:21, David Laight wrote:
> On Fri, 19 Sep 2025 14:11:37 +0200
> Christian König <christian.koenig@amd.com> wrote:
>
>> On 19.09.25 12:17, Eliav Farber wrote:
>>> This series includes a total of 27 patches, to align minmax.h of
>>> v5.15.y with v6.17-rc6.
>>>
>>> The set consists of 24 commits that directly update minmax.h:
>>> 1) 92d23c6e9415 ("overflow, tracing: Define the is_signed_type() macro
>>> once")
>>> 2) 5efcecd9a3b1 ("minmax: sanity check constant bounds when clamping")
>>> 3) 2122e2a4efc2 ("minmax: clamp more efficiently by avoiding extra
>>> comparison")
>>> 4) f9bff0e31881 ("minmax: add in_range() macro")
>>> 5) c952c748c7a9 ("minmax: Introduce {min,max}_array()")
>>> 6) 5e57418a2031 ("minmax: deduplicate __unconst_integer_typeof()")
>>> 7) f6e9d38f8eb0 ("minmax: fix header inclusions")
>>> 8) d03eba99f5bf ("minmax: allow min()/max()/clamp() if the arguments
>>> have the same signedness.")
>>> 9) f4b84b2ff851 ("minmax: fix indentation of __cmp_once() and
>>> __clamp_once()")
>>> 10) 4ead534fba42 ("minmax: allow comparisons of 'int' against 'unsigned
>>> char/short'")
>>> 11) 867046cc7027 ("minmax: relax check to allow comparison between
>>> unsigned arguments and signed constants")
>>> 12) 3a7e02c040b1 ("minmax: avoid overly complicated constant
>>> expressions in VM code")
>>> 14) 017fa3e89187 ("minmax: simplify and clarify min_t()/max_t()
>>> implementation")
>>> 15) 1a251f52cfdc ("minmax: make generic MIN() and MAX() macros
>>> available everywhere")
>>> 18) dc1c8034e31b ("minmax: simplify min()/max()/clamp()
>>> implementation")
>>> 19) 22f546873149 ("minmax: improve macro expansion and type
>>> checking")
>>> 20) 21b136cc63d2 ("minmax: fix up min3() and max3() too")
>>> 21) 71ee9b16251e ("minmax.h: add whitespace around operators and after
>>> commas")
>>> 22) 10666e992048 ("minmax.h: update some comments")
>>> 23) b280bb27a9f7 ("minmax.h: reduce the #define expansion of min(),
>>> max() and clamp()")
>>> 24) a5743f32baec ("minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi
>>> test in clamp()")
>>> 25) c3939872ee4a ("minmax.h: move all the clamp() definitions after the
>>> min/max() ones")
>>> 26) 495bba17cdf9 ("minmax.h: simplify the variants of clamp()")
>>> 27) 2b97aaf74ed5 ("minmax.h: remove some #defines that are only
>>> expanded once")
>>>
>>> 2 prerequisite commits that adjust users of MIN and MAX macros (to
>>> prevent compilation issues):
>>> 13) 4477b39c32fd ("minmax: add a few more MIN_T/MAX_T users")
>>> 17) cb04e8b1d2f2 ("minmax: don't use max() in situations that want a C
>>> constant expression")
>>>
>>> 1 additional commit introduced to resolve a build failures during the
>>> backport:
>>> 16) lib: zstd: drop local MIN/MAX macros in favor of generic ones
>>>
>>> The primary motivation is to bring in commit (8).
>>> In mainline, this change allows min()/max()/clamp() to accept mixed
>>> argument types when both share the same signedness.
>>> Backported patches to v5.10.y that use such forms trigger compiler
>>> warnings, which in turn cause build failures when -Werror is enabled.
>>>
>>> Originaly I aligned 5.10.y to 5.15.y, but David Laight commented that I
>>> need to pick up the later changes (from Linus) as well.
>>>
>>> Andy Shevchenko (2):
>>> minmax: deduplicate __unconst_integer_typeof()
>>> minmax: fix header inclusions
>>>
>>> Bart Van Assche (1):
>>> overflow, tracing: Define the is_signed_type() macro once
>>>
>>> David Laight (11):
>>> minmax: allow min()/max()/clamp() if the arguments have the same
>>> signedness.
>>> minmax: fix indentation of __cmp_once() and __clamp_once()
>>> minmax: allow comparisons of 'int' against 'unsigned char/short'
>>> minmax: relax check to allow comparison between unsigned arguments and
>>> signed constants
>>> minmax.h: add whitespace around operators and after commas
>>> minmax.h: update some comments
>>> minmax.h: reduce the #define expansion of min(), max() and clamp()
>>> minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
>>> minmax.h: move all the clamp() definitions after the min/max() ones
>>> minmax.h: simplify the variants of clamp()
>>> minmax.h: remove some #defines that are only expanded once
>>>
>>> Eliav Farber (1):
>>> lib: zstd: drop local MIN/MAX macros in favor of generic ones
>>>
>>> Herve Codina (1):
>>> minmax: Introduce {min,max}_array()
>>>
>>> Jason A. Donenfeld (2):
>>> minmax: sanity check constant bounds when clamping
>>> minmax: clamp more efficiently by avoiding extra comparison
>>>
>>> Linus Torvalds (8):
>>> minmax: avoid overly complicated constant expressions in VM code
>>> minmax: add a few more MIN_T/MAX_T users
>>> minmax: simplify and clarify min_t()/max_t() implementation
>>> minmax: make generic MIN() and MAX() macros available everywhere
>>> minmax: don't use max() in situations that want a C constant
>>> expression
>>> minmax: simplify min()/max()/clamp() implementation
>>> minmax: improve macro expansion and type checking
>>> minmax: fix up min3() and max3() too
>>>
>>> Matthew Wilcox (Oracle) (1):
>>> minmax: add in_range() macro
>>>
>>> arch/arm/mm/pageattr.c | 6 +-
>>> arch/um/drivers/mconsole_user.c | 2 +
>>> arch/x86/mm/pgtable.c | 2 +-
>>
>>> drivers/edac/sb_edac.c | 4 +-
>>> drivers/edac/skx_common.h | 1 -
>>> .../drm/amd/display/modules/hdcp/hdcp_ddc.c | 2 +
>>> .../drm/amd/pm/powerplay/hwmgr/ppevvmath.h | 14 +-
>>> .../drm/arm/display/include/malidp_utils.h | 2 +-
>>> .../display/komeda/komeda_pipeline_state.c | 24 +-
>>> drivers/gpu/drm/drm_color_mgmt.c | 2 +-
>>> drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 6 -
>>> drivers/gpu/drm/radeon/evergreen_cs.c | 2 +
>>> drivers/hwmon/adt7475.c | 24 +-
>>> drivers/input/touchscreen/cyttsp4_core.c | 2 +-
>>> drivers/md/dm-integrity.c | 2 +-
>>> drivers/media/dvb-frontends/stv0367_priv.h | 3 +
>>> .../net/ethernet/chelsio/cxgb3/cxgb3_main.c | 18 +-
>>> .../net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
>>> drivers/net/fjes/fjes_main.c | 4 +-
>>> drivers/nfc/pn544/i2c.c | 2 -
>>> drivers/platform/x86/sony-laptop.c | 1 -
>>> drivers/scsi/isci/init.c | 6 +-
>>
>> I do see the value to backport the infrastructure, but why are driver specific changes backported as well?
>
> They will be about removing local definitions of MIN() and MAX() freeing
> them up for simple implementations (usable as constant initialisers) and then
> using them in places where the compound statements in min() and max() can't
> be used.
>
> Linus did all those changes - so he didn't have to wait for the maintainers
> to apply the changes (etc).

Sounds reasonable, feel free to add my acked-by for radeon and amdgpu driver changes.

Regards,
Christian.

>
> David
>
>>
>> I mean the changes are most likely correct but also not valuable in anyway as bug fix.
>>
>> Regards,
>> Christian.
>>
>>> .../pci/hive_isp_css_include/math_support.h | 5 -
>>> fs/btrfs/misc.h | 2 -
>>> fs/btrfs/tree-checker.c | 2 +-
>>> fs/ext2/balloc.c | 2 -
>>> fs/ext4/ext4.h | 2 -
>>> fs/ufs/util.h | 6 -
>>> include/linux/compiler.h | 15 +
>>> include/linux/minmax.h | 267 ++++++++++++++----
>>> include/linux/overflow.h | 1 -
>>> include/linux/trace_events.h | 2 -
>>> kernel/trace/preemptirq_delay_test.c | 2 -
>>> lib/btree.c | 1 -
>>> lib/decompress_unlzma.c | 2 +
>>> lib/logic_pio.c | 3 -
>>> lib/vsprintf.c | 2 +-
>>> lib/zstd/zstd_internal.h | 2 -
>>> mm/zsmalloc.c | 1 -
>>> net/ipv4/proc.c | 2 +-
>>> net/ipv6/proc.c | 2 +-
>>> net/netfilter/nf_nat_core.c | 6 +-
>>> net/tipc/core.h | 2 +-
>>> net/tipc/link.c | 10 +-
>>> 44 files changed, 306 insertions(+), 164 deletions(-)
>>>
>>
>>
>