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Donenfeld" To: mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc/vdso: allow r30 in vDSO code generation of getrandom Message-ID: References: <20240925175021.1526936-2-Jason@zx2c4.com> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Post: List-Subscribe: , , List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240925175021.1526936-2-Jason@zx2c4.com> On Wed, Sep 25, 2024 at 07:50:22PM +0200, Jason A. Donenfeld wrote: > For gettimeofday, -ffixed-r30 was passed to work around a bug in Go > code, where the vDSO trampoline forgot to save and restore this register > across function calls. But Go requires a different trampoline for every > call, and there's no reason that new Go code needs to be broken and add > more bugs. So remove -ffixed-r30 for getrandom. Strangely, I am _unable to_ make the Go code not crash with this patch applied. I'm not quite sure what I'm doing wrong yet, or if this points to another issue.