linux/arch/powerpc
William A. Kennington III 71e24d7731 powerpc/opal: Fix EBUSY bug in acquiring tokens
The current code checks the completion map to look for the first token
that is complete. In some cases, a completion can come in but the
token can still be on lease to the caller processing the completion.
If this completed but unreleased token is the first token found in the
bitmap by another tasks trying to acquire a token, then the
__test_and_set_bit call will fail since the token will still be on
lease. The acquisition will then fail with an EBUSY.

This patch reorganizes the acquisition code to look at the
opal_async_token_map for an unleased token. If the token has no lease
it must have no outstanding completions so we should never see an
EBUSY, unless we have leased out too many tokens. Since
opal_async_get_token_inrerruptible is protected by a semaphore, we
will practically never see EBUSY anymore.

Fixes: 8d72482322 ("powerpc/powernv: Infrastructure to support OPAL async completion")
Signed-off-by: William A. Kennington III <wak@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 20:17:41 +11:00
..
boot powerpc: dts: acadia: DT fix s/#interrupts-parent/#interrupt-parent/ 2017-10-22 12:08:31 +02:00
configs powerpc/configs: Enable I2C_CHARDEV for pseries and powernv 2017-10-22 12:08:31 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-05-02 15:53:46 -07:00
include powerpc/eeh: Stop using do_gettimeofday() 2017-11-06 17:40:00 +11:00
kernel powerpc/eeh: Stop using do_gettimeofday() 2017-11-06 17:40:00 +11:00
kvm KVM: PPC: Book3S HV: Handle host system reset in guest mode 2017-11-06 16:48:06 +11:00
lib powerpc/lib/sstep: Fix fixed-point shift instructions that set CA32 2017-10-04 11:28:04 +11:00
math-emu Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mm powerpc/mm: Add a CONFIG option to choose if radix is used by default 2017-11-06 16:48:15 +11:00
net bpf: take advantage of stack_depth tracking in powerpc JIT 2017-11-06 16:48:16 +11:00
oprofile powerpc/oprofile: Use setup_timer() helper 2017-10-04 11:28:01 +11:00
perf powerpc/perf/hv-24x7: Fix incorrect comparison in memord 2017-10-22 12:08:31 +02:00
platforms powerpc/opal: Fix EBUSY bug in acquiring tokens 2017-11-06 20:17:41 +11:00
purgatory powerpc/asm: Convert .llong directives to .8byte 2017-08-31 14:26:47 +10:00
sysdev powerpc/ipic: Fix status get and status clear 2017-11-06 16:48:13 +11:00
tools powerpc/64: Tool to check head sections location sanity 2017-05-30 14:59:51 +10:00
xmon powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64 2017-11-06 16:48:14 +11:00
Kconfig powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64 2017-11-06 16:48:14 +11:00
Kconfig.debug powerpc: Disable the fast-endian switch syscall by default 2017-10-22 12:08:31 +02:00
Makefile Merge branch 'fixes' into next 2017-08-23 22:20:10 +10:00
Makefile.postlink powerpc/64: Tool to check head sections location sanity 2017-05-30 14:59:51 +10:00