Re: [PATCH v3 15/18] arm/arm64: smccc: Make function identifiers an unsigned quantity

2018-02-01 Thread Ard Biesheuvel
On 1 February 2018 at 12:40, Robin Murphy wrote: > On 01/02/18 11:46, Marc Zyngier wrote: >> >> Function identifiers are a 32bit, unsigned quantity. But we never >> tell so to the compiler, resulting in the following: >> >> 4ac: b26187e0mov x0,

Re: [PATCH v3 15/18] arm/arm64: smccc: Make function identifiers an unsigned quantity

2018-02-01 Thread Robin Murphy
On 01/02/18 11:46, Marc Zyngier wrote: Function identifiers are a 32bit, unsigned quantity. But we never tell so to the compiler, resulting in the following: 4ac: b26187e0mov x0, #0x8001 We thus rely on the firmware narrowing it for us, which is not always a

[PATCH v3 15/18] arm/arm64: smccc: Make function identifiers an unsigned quantity

2018-02-01 Thread Marc Zyngier
Function identifiers are a 32bit, unsigned quantity. But we never tell so to the compiler, resulting in the following: 4ac: b26187e0mov x0, #0x8001 We thus rely on the firmware narrowing it for us, which is not always a reasonable expectation. Cc: