lkml.org 
[lkml]   [2019]   [Jan]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 3/3] x86/platform/UV: use efi_runtime_sem to serialise BIOS calls
On Wed, 9 Jan 2019 at 11:46, Hedi Berriche <hedi.berriche@hpe.com> wrote:
>
> Calls into UV firmware must be protected against concurrency, use the
> now visible efi_runtime_sem lock to serialise them.
>
> Signed-off-by: Hedi Berriche <hedi.berriche@hpe.com>
> Reviewed-by: Russ Anderson <rja@hpe.com>
> Reviewed-by: Mike Travis <mike.travis@hpe.com>
> Reviewed-by: Dimitri Sivanich <sivanich@hpe.com>
> Reviewed-by: Steve Wahl <steve.wahl@hpe.com>

> ---
> arch/x86/include/asm/uv/bios.h | 3 ++-
> arch/x86/platform/uv/bios_uv.c | 25 ++++++++++++++++++++++---
> 2 files changed, 24 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/include/asm/uv/bios.h b/arch/x86/include/asm/uv/bios.h
> index 4eee646544b2..33e94aa0b1ff 100644
> --- a/arch/x86/include/asm/uv/bios.h
> +++ b/arch/x86/include/asm/uv/bios.h
> @@ -48,7 +48,8 @@ enum {
> BIOS_STATUS_SUCCESS = 0,
> BIOS_STATUS_UNIMPLEMENTED = -ENOSYS,
> BIOS_STATUS_EINVAL = -EINVAL,
> - BIOS_STATUS_UNAVAIL = -EBUSY
> + BIOS_STATUS_UNAVAIL = -EBUSY,
> + BIOS_STATUS_ABORT = -EINTR

Nit: please add a trailing comma so the next patch looks cleaner.

> };
>
> /* Address map parameters */
> diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
> index cd05af157763..92f960798e20 100644
> --- a/arch/x86/platform/uv/bios_uv.c
> +++ b/arch/x86/platform/uv/bios_uv.c
> @@ -29,7 +29,8 @@
>
> struct uv_systab *uv_systab;
>
> -s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
> +s64 __uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
> + u64 a4, u64 a5)
> {
> struct uv_systab *tab = uv_systab;
> s64 ret;
> @@ -44,13 +45,26 @@ s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
> * If EFI_OLD_MEMMAP is set, we need to fall back to using our old EFI
> * callback method, which uses efi_call() directly, with the kernel page tables:
> */
> - if (unlikely(test_bit(EFI_OLD_MEMMAP, &efi.flags)))
> + if (unlikely(efi_enabled(EFI_OLD_MEMMAP)))

This is an unrelated change. You should at least mention it in the
commit log, or put it in a separate patch.

> ret = efi_call((void *)__va(tab->function), (u64)which, a1, a2, a3, a4, a5);
> else
> ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4, a5);
>
> return ret;
> }
> +
> +s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
> +{
> + s64 ret;
> +
> + if (down_interruptible(&efi_runtime_sem))
> + return BIOS_STATUS_ABORT;
> +
> + ret = __uv_bios_call(which, a1, a2, a3, a4, a5);
> + up(&efi_runtime_sem);
> +
> + return ret;
> +}
> EXPORT_SYMBOL_GPL(uv_bios_call);
>
> s64 uv_bios_call_irqsave(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
> @@ -59,10 +73,15 @@ s64 uv_bios_call_irqsave(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
> unsigned long bios_flags;
> s64 ret;
>
> + if (down_interruptible(&efi_runtime_sem))
> + return BIOS_STATUS_ABORT;
> +
> local_irq_save(bios_flags);
> - ret = uv_bios_call(which, a1, a2, a3, a4, a5);
> + ret = __uv_bios_call(which, a1, a2, a3, a4, a5);
> local_irq_restore(bios_flags);
>
> + up(&efi_runtime_sem);
> +
> return ret;
> }
>
> --
> 2.20.0
>

\
 
 \ /
  Last update: 2019-01-26 15:12    [W:0.078 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site