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authorHedi Berriche <hedi.berriche@hpe.com>2019-02-13 19:34:13 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-02-20 10:29:14 +0100
commit0a4908fafb770024606629c98ee7c8ae866add1b (patch)
tree88c23e2a18fd3f3aeb09f3e24ae7b7930ae05b91
parentebf5838d6da6a525c78ed55b3ee54c1a4e868d67 (diff)
x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls
commit f331e766c4be33f4338574f3c9f7f77e98ab4571 upstream. Calls into UV firmware must be protected against concurrency, expose the efi_runtime_lock to the UV platform, and use it to serialise UV BIOS calls. Signed-off-by: Hedi Berriche <hedi.berriche@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Russ Anderson <rja@hpe.com> Reviewed-by: Dimitri Sivanich <sivanich@hpe.com> Reviewed-by: Mike Travis <mike.travis@hpe.com> Cc: Andy Shevchenko <andy@infradead.org> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Darren Hart <dvhart@infradead.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-efi <linux-efi@vger.kernel.org> Cc: platform-driver-x86@vger.kernel.org Cc: stable@vger.kernel.org # v4.9+ Cc: Steve Wahl <steve.wahl@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190213193413.25560-5-hedi.berriche@hpe.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/include/asm/uv/bios.h8
-rw-r--r--arch/x86/platform/uv/bios_uv.c23
-rw-r--r--drivers/firmware/efi/runtime-wrappers.c7
3 files changed, 35 insertions, 3 deletions
diff --git a/arch/x86/include/asm/uv/bios.h b/arch/x86/include/asm/uv/bios.h
index e652a7cc6186..3f697a9e3f59 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,
};
/* Address map parameters */
@@ -167,4 +168,9 @@ extern long system_serial_number;
extern struct kobject *sgi_uv_kobj; /* /sys/firmware/sgi_uv */
+/*
+ * EFI runtime lock; cf. firmware/efi/runtime-wrappers.c for details
+ */
+extern struct semaphore __efi_uv_runtime_lock;
+
#endif /* _ASM_X86_UV_BIOS_H */
diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index 4a6a5a26c582..eb33432f2f24 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)
+static 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;
@@ -51,6 +52,19 @@ s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 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_uv_runtime_lock))
+ return BIOS_STATUS_ABORT;
+
+ ret = __uv_bios_call(which, a1, a2, a3, a4, a5);
+ up(&__efi_uv_runtime_lock);
+
+ 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_uv_runtime_lock))
+ 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_uv_runtime_lock);
+
return ret;
}
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
index 8903b9ccfc2b..e2abfdb5cee6 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -147,6 +147,13 @@ void efi_call_virt_check_flags(unsigned long flags, const char *call)
static DEFINE_SEMAPHORE(efi_runtime_lock);
/*
+ * Expose the EFI runtime lock to the UV platform
+ */
+#ifdef CONFIG_X86_UV
+extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock);
+#endif
+
+/*
* Calls the appropriate efi_runtime_service() with the appropriate
* arguments.
*