linux-kernel - Re: [PATCH v2] kvm: x86: mmu: Add cast to negated bitmasks in update_permission

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 25 Jun 2018 10:50:55 -0700
From:   Joe Perches <joe@...ches.com>
To:     Matthias Kaehlcke <mka@...omium.org>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     Radim Krčmář <rkrcmar@...hat.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "H . Peter Anvin" <hpa@...or.com>, x86@...nel.org,
        kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Nick Desaulniers <ndesaulniers@...gle.com>
Subject: Re: [PATCH v2] kvm: x86: mmu: Add cast to negated bitmasks in
 update_permission_bitmask()

On Mon, 2018-06-25 at 10:35 -0700, Matthias Kaehlcke wrote:
> Some other instances of the warning that have been addressed are:
> commit 644d87dccdc69cf79834a72ed0c889580d6af32a
> commit e2a5dca753d1cdc3212519023ed8a13e13f5495b
> commit dae1a432ab1fe79ae53129ededeaece35a2dc14d
> commit d1600401faad4bc186bfdb291d8af644465e20bd
> commit a45463cbf3f9dcdae683033c256f50bded513d6a
 
I think all these implicit conversion warnings are senseless
and should really be silenced by setting them only to be
output at W=3 with all the other non-static and generally
unnecessary signed/unsigned conversions

---
 scripts/Makefile.extrawarn | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 8d5357053f86..9b1d0d59e8d0 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -46,6 +46,7 @@ warning-2 += $(call cc-option, -Wunused-macros)
 warning-3 := -Wbad-function-cast
 warning-3 += -Wcast-qual
 warning-3 += -Wconversion
+warning-3 += $(call cc-option -Wconstant-conversion)
 warning-3 += -Wpacked
 warning-3 += -Wpadded
 warning-3 += -Wpointer-arith