Le 16/02/2021 à 20:01, Richard Purdie a écrit :
> When using qemu-i386 to build qemux86 webkitgtk on musl, it sits in an
> infinite loop of mremap calls of ever decreasing/increasing addresses.
>
> I suspect something in the musl memory allocation code loops
> indefinitely if it only sees ENOMEM and only exits when it hits other
> errors such as EFAULT or EINVAL.
>
> According to the docs, trying to mremap outside the address space
> can/should return EFAULT and changing this allows the build to succeed.
>
> A better return value for the other cases of invalid addresses is
> EINVAL rather than ENOMEM so adjust the other part of the test to this.
>
> Signed-off-by: Richard Purdie <richard.pur...@linuxfoundation.org
>
> Index: qemu-5.2.0/linux-user/mmap.c
> ===================================================================
> --- qemu-5.2.0.orig/linux-user/mmap.c
> +++ qemu-5.2.0/linux-user/mmap.c
> @@ -722,12 +722,14 @@ abi_long target_mremap(abi_ulong old_add
> int prot;
> void *host_addr;
>
> - if (!guest_range_valid(old_addr, old_size) ||
> - ((flags & MREMAP_FIXED) &&
> - !guest_range_valid(new_addr, new_size)) ||
> - ((flags & MREMAP_MAYMOVE) == 0 &&
> - !guest_range_valid(old_addr, new_size))) {
> - errno = ENOMEM;
> + if (!guest_range_valid(old_addr, old_size)) {
> + errno = EFAULT;
> + return -1;
> + }
> +
> + if (((flags & MREMAP_FIXED) && !guest_range_valid(new_addr, new_size)) ||
> + ((flags & MREMAP_MAYMOVE) == 0 && !guest_range_valid(old_addr,
> new_size))) {
> + errno = EINVAL;
> return -1;
> }
>
>
>
Reviewed-by: Laurent Vivier <laur...@vivier.eu>
